WorldWideScience

Sample records for manufacture high damage

  1. Wide and High Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Post, Brian K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Roschli, Alex C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-03-01

    The goal of this project is to develop and demonstrate the enabling technologies for Wide and High Additive Manufacturing (WHAM). WHAM will open up new areas of U.S. manufacturing for very large tooling in support of the transportation and energy industries, significantly reducing cost and lead time. As with Big Area Additive Manufacturing (BAAM), the initial focus is on the deposition of composite materials.

  2. Damage evolution and failure mechanisms in additively manufactured stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, Holly D., E-mail: carlton4@llnl.gov [Materials Engineering Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Haboub, Abdel [Lincoln University, Life and Physical Sciences Department, 820 Chestnut St, Jefferson City, MO 65101 (United States); Gallegos, Gilbert F. [Materials Engineering Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Parkinson, Dilworth Y.; MacDowell, Alastair A. [Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

    2016-01-10

    In situ tensile tests were performed on additively manufactured austenitic stainless steel to track damage evolution within the material. For these experiments Synchrotron Radiation micro-Tomography was used to measure three-dimensional pore volume, distribution, and morphology in stainless steel at the micrometer length-scale while tensile loading was applied. The results showed that porosity distribution played a larger role in affecting the fracture mechanisms than measured bulk density. Specifically, additively manufactured stainless steel specimens with large inhomogeneous void distributions displayed a flaw-dominated failure where cracks were shown to initiate at pre-existing voids, while annealed additively manufactured stainless steel specimens, which contained low porosity and randomly distributed pores, displayed fracture mechanisms that closely resembled wrought metal.

  3. High energy beam manufacturing technologies

    International Nuclear Information System (INIS)

    Geskin, E.S.; Leu, M.C.

    1989-01-01

    Technological progress continues to enable us to utilize ever widening ranges of physical and chemical conditions for material processing. The increasing cost of energy, raw materials and environmental control make implementation of advanced technologies inevitable. One of the principal avenues in the development of material processing is the increase of the intensity, accuracy, flexibility and stability of energy flow to the processing site. The use of different forms of energy beams is an effective way to meet these sometimes incompatible requirements. The first important technological applications of high energy beams were welding and flame cutting. Subsequently a number of different kinds of beams have been used to solve different problems of part geometry control and improvement of surface characteristics. Properties and applications of different specific beams were subjects of a number of fundamental studies. It is important now to develop a generic theory of beam based manufacturing. The creation of a theory dealing with general principles of beam generation and beam-material interaction will enhance manufacturing science as well as practice. For example, such a theory will provide a format approach for selection and integration of different kinds of beams for a particular application. And obviously, this theory will enable us to integrate the knowledge bases of different manufacturing technologies. The War of the Worlds by H. G. Wells, as well as a number of more technical, although less exciting, publications demonstrate both the feasibility and effectiveness of the generic approach to the description of beam oriented technology. Without any attempt to compete with Wells, we still hope that this volume will contribute to the creation of the theory of beam oriented manufacturing

  4. Lymphocyte DNA damage in elevator manufacturing workers in Guangzhou, China.

    Science.gov (United States)

    Lam, Tai Hing; Zhu, Chang Qi; Jiang, Chao Qiang

    2002-03-25

    To study the effect of smoking, passive smoking, alcohol drinking, and occupational exposure to low level of benzene on DNA strand breaks in elevator manufacturing workers in Guangzhou, China. Three hundred and fifty-nine workers (252 men and 107 women) of a modern elevator manufacturing factory, 205 were from production departments and 154 from managerial department. Information on the workers' health conditions, smoking, passive smoking, alcohol consumption and occupational exposure history was collected by personal interview. Lymphocyte DNA damage was measured by the Comet assay. None of the women smoked and 20.6% of the men were daily smokers. In non-smokers, the prevalence of passive smoking at work was 25% for men and 11.2% for women, and at home, 37.8 and 48.6%, respectively. Smoking significantly increased tail moment (P<0.001). Daily smokers had the largest tail moment (geometric mean, 95% CI) (0.93 microm (0.81-0.94)), followed by occasional smokers (0.76 microm (0.59-0.95)), ex-smokers (0.70 microm (0.58-0.85)), and never smokers (0.56 microm (0.53-0.60)). Tail moment increased significantly with daily tobacco consumption (cigarettes per day) (r=0.26, P<0.001) after adjusting for age, gender, occupational exposure, passive smoking, and drinking. Analysis of covariance (ANCOVA) showed that smoking (P<0.001), passive smoking at home (P=0.026), occupational exposure (P<0.001), male gender (P<0.001), and age (P=0.001) had independent effects on tail moment, whereas passive smoking at work and alcohol drinking had no significant effect. Smoking, passive smoking at home, male gender, age and occupational exposure independently increased lymphocyte DNA strand breaks. The presence of excess DNA damage under low level of occupational exposure to benzene or other solvents suggest that the current allowance concentrations may not be safe to prevent genotoxicity.

  5. Cost-Effective Manufacturing of Damage-Tolerant Integral Armor

    National Research Council Canada - National Science Library

    Fink, Bruce

    2000-01-01

    ...) technology demonstrator and Crusader self-propelled howitzer platforms. Present integral armor manufacturing processes involve adhesive bonding of a composite structure with ballistic armor tiles, spall shield, and nuisance cover...

  6. Manufacturing of High Entropy Alloys

    Science.gov (United States)

    Jablonski, Paul D.; Licavoli, Joseph J.; Gao, Michael C.; Hawk, Jeffrey A.

    2015-07-01

    High entropy alloys (HEAs) have generated interest in recent years due to their unique positioning within the alloy world. By incorporating a number of elements in high proportion they have high configurational entropy, and thus they hold the promise of interesting and useful properties such as enhanced strength and phase stability. The present study investigates the microstructure of two single-phase face-centered cubic (FCC) HEAs, CoCrFeNi and CoCrFeNiMn, with special attention given to melting, homogenization and thermo-mechanical processing. Large-scale ingots were made by vacuum induction melting to avoid the extrinsic factors inherent in small-scale laboratory button samples. A computationally based homogenization heat treatment was applied to both alloys in order to eliminate segregation due to normal ingot solidification. The alloys fabricated well, with typical thermo-mechanical processing parameters being employed.

  7. Structure/property (constitutive and dynamic strength/damage) characterization of additively manufactured 316L SS

    Science.gov (United States)

    Gray, G. T., III; Livescu, V.; Rigg, P. A.; Trujillo, C. P.; Cady, C. M.; Chen, S. R.; Carpenter, J. S.; Lienert, T. J.; Fensin, S.

    2015-09-01

    For additive manufacturing (AM), the certification and qualification paradigm needs to evolve as there exists no "ASTM-type" additive manufacturing certified process or AM-material produced specifications. Accordingly, utilization of AM materials to meet engineering applications requires quantification of the constitutive properties of these evolving materials in comparison to conventionally-manufactured metals and alloys. Cylinders of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM) equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS is detailed in both the as-built condition and following heat-treatments designed to obtain full recrystallization. The constitutive behavior as a function of strain rate and temperature is presented and compared to that of nominal annealed wrought 316L SS plate. The dynamic damage evolution and failure response of all three materials was probed using flyer-plate impact driven spallation experiments at a peak stress of 4.5 GPa to examine incipient spallation response. The spall strength of AM-produced 316L SS was found to be very similar for the peak shock stress studied to that of annealed wrought or AM-316L SS following recrystallization. The damage evolution as a function of microstructure was characterized using optical metallography.

  8. Structure/property (constitutive and dynamic strength/damage characterization of additively manufactured 316L SS

    Directory of Open Access Journals (Sweden)

    Gray III G.T.

    2015-01-01

    Full Text Available For additive manufacturing (AM, the certification and qualification paradigm needs to evolve as there exists no “ASTM-type” additive manufacturing certified process or AM-material produced specifications. Accordingly, utilization of AM materials to meet engineering applications requires quantification of the constitutive properties of these evolving materials in comparison to conventionally-manufactured metals and alloys. Cylinders of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS is detailed in both the as-built condition and following heat-treatments designed to obtain full recrystallization. The constitutive behavior as a function of strain rate and temperature is presented and compared to that of nominal annealed wrought 316L SS plate. The dynamic damage evolution and failure response of all three materials was probed using flyer-plate impact driven spallation experiments at a peak stress of 4.5 GPa to examine incipient spallation response. The spall strength of AM-produced 316L SS was found to be very similar for the peak shock stress studied to that of annealed wrought or AM-316L SS following recrystallization. The damage evolution as a function of microstructure was characterized using optical metallography.

  9. Ionization versus displacement damage effects in proton irradiated CMOS sensors manufactured in deep submicron process

    International Nuclear Information System (INIS)

    Goiffon, V.; Magnan, P.; Saint-Pe, O.; Bernard, F.; Rolland, G.

    2009-01-01

    Proton irradiation effects have been studied on CMOS image sensors manufactured in a 0.18μm technology dedicated to imaging. The ionizing dose and displacement damage effects were discriminated and localized thanks to 60 Co irradiations and large photodiode reverse current measurements. The only degradation observed was a photodiode dark current increase. It was found that ionizing dose effects dominate this rise by inducing generation centers at the interface between shallow trench isolations and depleted silicon regions. Displacement damages are is responsible for a large degradation of dark current non-uniformity. This work suggests that designing a photodiode tolerant to ionizing radiation can mitigate an important part of proton irradiation effects.

  10. Low Cost Lithography Tool for High Brightness LED Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Hawryluk; Emily True

    2012-06-30

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  11. Laser additive manufacturing of high-performance materials

    CERN Document Server

    Gu, Dongdong

    2015-01-01

    This book entitled “Laser Additive Manufacturing of High-Performance Materials” covers the specific aspects of laser additive manufacturing of high-performance new materials components based on an unconventional materials incremental manufacturing philosophy, in terms of materials design and preparation, process control and optimization, and theories of physical and chemical metallurgy. This book describes the capabilities and characteristics of the development of new metallic materials components by laser additive manufacturing process, including nanostructured materials, in situ composite materials, particle reinforced metal matrix composites, etc. The topics presented in this book, similar as laser additive manufacturing technology itself, show a significant interdisciplinary feature, integrating laser technology, materials science, metallurgical engineering, and mechanical engineering. This is a book for researchers, students, practicing engineers, and manufacturing industry professionals interested i...

  12. Converting Hangar High Expansion Foam Systems to Prevent Cockpit Damage: Full-Scale Validation Tests

    Science.gov (United States)

    2017-09-01

    AFCEC-CO-TY-TR-2018-0001 CONVERTING HANGAR HIGH EXPANSION FOAM SYSTEMS TO PREVENT COCKPIT DAMAGE: FULL-SCALE VALIDATION TESTS Gerard G...manufacturer, or otherwise does not constitute or imply its endorsement, recommendation , or approval by the United States Air Force. The views and...09-2017 Final Test Report May 2017 Converting Hangar High Expansion Foam Systems to Prevent Cockpit Damage: Full-Scale Validation Tests N00173-15-D

  13. Advances in High Temperature Materials for Additive Manufacturing

    Science.gov (United States)

    Nordin, Nurul Amira Binti; Johar, Muhammad Akmal Bin; Ibrahim, Mohd Halim Irwan Bin; Marwah, Omar Mohd Faizan bin

    2017-08-01

    In today’s technology, additive manufacturing has evolved over the year that commonly known as 3D printing. Currently, additive manufacturing have been applied for many industries such as for automotive, aerospace, medical and other commercial product. The technologies are supported by materials for the manufacturing process to produce high quality product. Plus, additive manufacturing technologies has been growth from the lowest to moderate and high technology to fulfil manufacturing industries obligation. Initially from simple 3D printing such as fused deposition modelling (FDM), poly-jet, inkjet printing, to selective laser sintering (SLS), and electron beam melting (EBM). However, the high technology of additive manufacturing nowadays really needs high investment to carry out the process for fine products. There are three foremost type of material which is polymer, metal and ceramic used for additive manufacturing application, and mostly they were in the form of wire feedstock or powder. In circumstance, it is crucial to recognize the characteristics of each type of materials used in order to understand the behaviours of the materials on high temperature application via additive manufacturing. Therefore, this review aims to provide excessive inquiry and gather the necessary information for further research on additive material materials for high temperature application. This paper also proposed a new material based on powder glass, which comes from recycled tempered glass from automotive industry, having a huge potential to be applied for high temperature application. The technique proposed for additive manufacturing will minimize some cost of modelling with same quality of products compare to the others advanced technology used for high temperature application.

  14. High damage tolerance of electrochemically lithiated silicon

    Science.gov (United States)

    Wang, Xueju; Fan, Feifei; Wang, Jiangwei; Wang, Haoran; Tao, Siyu; Yang, Avery; Liu, Yang; Beng Chew, Huck; Mao, Scott X.; Zhu, Ting; Xia, Shuman

    2015-01-01

    Mechanical degradation and resultant capacity fade in high-capacity electrode materials critically hinder their use in high-performance rechargeable batteries. Despite tremendous efforts devoted to the study of the electro–chemo–mechanical behaviours of high-capacity electrode materials, their fracture properties and mechanisms remain largely unknown. Here we report a nanomechanical study on the damage tolerance of electrochemically lithiated silicon. Our in situ transmission electron microscopy experiments reveal a striking contrast of brittle fracture in pristine silicon versus ductile tensile deformation in fully lithiated silicon. Quantitative fracture toughness measurements by nanoindentation show a rapid brittle-to-ductile transition of fracture as the lithium-to-silicon molar ratio is increased to above 1.5. Molecular dynamics simulations elucidate the mechanistic underpinnings of the brittle-to-ductile transition governed by atomic bonding and lithiation-induced toughening. Our results reveal the high damage tolerance in amorphous lithium-rich silicon alloys and have important implications for the development of durable rechargeable batteries. PMID:26400671

  15. Grinding damage assessment on four high-strength ceramics.

    Science.gov (United States)

    Canneto, Jean-Jacques; Cattani-Lorente, Maria; Durual, Stéphane; Wiskott, Anselm H W; Scherrer, Susanne S

    2016-02-01

    The purpose of this study was to assess surface and subsurface damage on 4 CAD-CAM high-strength ceramics after grinding with diamond disks of 75 μm, 54 μm and 18 μm and to estimate strength losses based on damage crack sizes. The materials tested were: 3Y-TZP (Lava), dense Al2O3 (In-Ceram AL), alumina glass-infiltrated (In-Ceram ALUMINA) and alumina-zirconia glass-infiltrated (In-Ceram ZIRCONIA). Rectangular specimens with 2 mirror polished orthogonal sides were bonded pairwise together prior to degrading the top polished surface with diamond disks of either 75 μm, 54 μm or 18 μm. The induced chip damage was evaluated on the bonded interface using SEM for chip depth measurements. Fracture mechanics were used to estimate fracture stresses based on average and maximum chip depths considering these as critical flaws subjected to tension and to calculate possible losses in strength compared to manufacturer's data. 3Y-TZP was hardly affected by grinding chip damage viewed on the bonded interface. Average chip depths were of 12.7±5.2 μm when grinding with 75 μm diamond inducing an estimated loss of 12% in strength compared to manufacturer's reported flexural strength values of 1100 MPa. Dense alumina showed elongated chip cracks and was suffering damage of an average chip depth of 48.2±16.3 μm after 75 μm grinding, representing an estimated loss in strength of 49%. Grinding with 54 μm was creating chips of 32.2±9.1 μm in average, representing a loss in strength of 23%. Alumina glass-infiltrated ceramic was exposed to chipping after 75 μm (mean chip size=62.4±19.3 μm) and 54 μm grinding (mean chip size=42.8±16.6 μm), with respectively 38% and 25% estimated loss in strength. Alumina-zirconia glass-infiltrated ceramic was mainly affected by 75 μm grinding damage with a chip average size of 56.8±15.1 μm, representing an estimated loss in strength of 34%. All four ceramics were not exposed to critical chipping at 18 μm diamond grinding. Reshaping a

  16. Initiation and propagation of damage in actively cooled CFC armoured high heat flux components in fusion machines

    International Nuclear Information System (INIS)

    Chevet, G.; Schlosser, J.; Martin, E.; Herb, V.; Camus, G.; Escourbiac, F.

    2009-01-01

    Plasma facing components (PFCs) in magnetic confinement controlled fusion machines are armoured with carbon fibre composite (CFC) bonded to a copper alloy heat sink. The manufacturing process induces high level of residual stresses due to the thermal expansion mismatch between CFC and copper and PFCs have to withstand strong stress ranges during operation. To study the initiation and propagation of damage in the CFC part, the ONERA damage model is used to describe the behaviour of the N11 material. The finite element simulations show that the damage is located near the interface and develops during the manufacturing of the PFCs as a consequence of the high amplitude of shear stresses. Under high heat flux, stresses decrease and the damage does not evolve. Further studies will take into account the damageable behaviour of the composite/copper interface, which will lead to geometrical optimisations and better knowledge of the link between damage and conductivity.

  17. Additive Manufacturing for Highly Efficient Window Inserts CRADA Report

    Energy Technology Data Exchange (ETDEWEB)

    Roschli, Alex C. [ORNL; Chesser, Phillip C. [ORNL; Love, Lonnie J. [ORNL

    2018-04-01

    ORNL partnered with the Mackinac Technology Company to demonstrate how additive manufacturing can be used to create highly energy efficient window inserts for retrofit in pre-existing buildings. Many early iterations of the window inserts were fabricated using carbon fiber reinforced thermoplastics and polycarbonate films as a stand in for the low-e coated films produced by the Mackinac Technology Company. After demonstration of the proof of concept, i.e. custom window inserts with tensioned film, the materials used for the manufacture of the frames was more closely examined. Hollow particle-filled syntactic foam and low-density polymer composites formed by expandable microspheres were explored as the materials used to additively manufacture the frames of the inserts. It was concluded that low-cost retrofit window inserts in custom sizes could be easily fabricated using large scale additive manufacturing. Furthermore, the syntactic and expanded foams developed and tested satisfy the mechanical performance requirements for the application.

  18. Design and manufacture of high performance hollow engine valves by Additive Layer Manufacturing

    International Nuclear Information System (INIS)

    Cooper, D.; Thornby, J.; Blundell, N.; Henrys, R.; Williams, M.A.; Gibbons, G.

    2015-01-01

    Highlights: • High performance engine valve has been redesigned and optimised for and using ALM. • FEA was utilised to optimise and select a design for manufacture and testing. • Micro computed tomography was used in design and validation as an NDT technique. • Real world test of components was conducted to evaluate their performance. • Has demonstrated the potential for ALM in a high performance engineering context. - Abstract: Additive Layer Manufacture (ALM) of metallic components provides significant opportunities for the reduction of component weight, in order to realise improvements in vehicle fuel efficiency or performance. This paper examines the potential benefits of ALM with regard to reducing the weight of Internal Combustion Engine inlet or exhaust valves. A case study component is presented, for which an improved ALM design has been created, manufactured and evaluated. Micro-Computed Tomography (μ-CT) scanning was utilised to reverse engineer an original component, and to assess the ALM component’s internal geometry and material integrity. The case study valve was re-designed using Finite Element Analysis (FEA) to select a light weighted design which provides a conservative 9.4 g, (20%) weight saving on the Original Equipment Manufacturer (OEM) component. An engine test of over 175,000 cycles at between 2000 and 9500 rpm was conducted, after which μ-CT scanning confirmed no evidence of internal cracking, failure or significant deformation

  19. Friction Stir Additive Manufacturing: Route to High Structural Performance

    Science.gov (United States)

    Palanivel, S.; Sidhar, H.; Mishra, R. S.

    2015-03-01

    Aerospace and automotive industries provide the next big opportunities for additive manufacturing. Currently, the additive industry is confronted with four major challenges that have been identified in this article. These challenges need to be addressed for the additive technologies to march into new frontiers and create additional markets. Specific potential success in the transportation sectors is dependent on the ability to manufacture complicated structures with high performance. Most of the techniques used for metal-based additive manufacturing are fusion based because of their ability to fulfill the computer-aided design to component vision. Although these techniques aid in fabrication of complex shapes, achieving high structural performance is a key problem due to the liquid-solid phase transformation. In this article, friction stir additive manufacturing (FSAM) is shown as a potential solid-state process for attaining high-performance lightweight alloys for simpler geometrical applications. To illustrate FSAM as a high-performance route, manufactured builds of Mg-4Y-3Nd and AA5083 are shown as examples. In the Mg-based alloy, an average hardness of 120 HV was achieved in the built structure and was significantly higher than that of the base material (97 HV). Similarly for the Al-based alloy, compared with the base hardness of 88 HV, the average built hardness was 104 HV. A potential application of FSAM is illustrated by taking an example of a simple stiffener assembly.

  20. Radiation damage in a high Ni weld

    International Nuclear Information System (INIS)

    Brumovsky, M.; Kytka, M.; Kopriva, R.

    2015-01-01

    WWER-1000 RPV weld metals are characterized by a high content of nickel, mostly about 1.7 mass % with content of manganese around 0.8 mass % with a very low copper content - about 0.05 mass %. In such material some late blooming phase effect should be observed during irradiation. Such typical weld material was irradiated in the experimental reactor LVR-15 in N RI Rez at the irradiation temperature 290 C degrees and at five neutron fluences from 1.5 to 9.5 *10 23 m -2 (E>1 MeV). Charpy V-notch impact tests, static fracture toughness tests, tensile and hardness measurement were performed to obtain effect of neutron fluence on radiation hardening as well as embrittlement. Neutron fluence dependences of all these property changes have monotonic character but with a high neutron embrittlement exponent around 0.8. Scanning electron microscope of fracture surfaces showed no or very small portion of intercrystalline fracture. Transmission electron microscopy was performed on specimens from all neutron fluences. Only low density of black-dot damage has been observed. It is assumed that most of defect are dislocation loops. The late blooming phase which may be observed from results of mechanical properties are probably below the resolution of the used JEM-2010, i.e. 1.5 nm. (authors)

  1. Additive Manufacturing of High-Entropy Alloys by Laser Processing

    NARCIS (Netherlands)

    Ocelik, V.; Janssen, Niels; Smith, Stefan; De Hosson, J. Th M.

    This contribution concentrates on the possibilities of additive manufacturing of high-entropy clad layers by laser processing. In particular, the effects of the laser surface processing parameters on the microstructure and hardness of high-entropy alloys (HEAs) were examined. AlCoCrFeNi alloys with

  2. Additively manufactured hierarchical stainless steels with high strength and ductility

    Science.gov (United States)

    Wang, Y. Morris; Voisin, Thomas; McKeown, Joseph T.; Ye, Jianchao; Calta, Nicholas P.; Li, Zan; Zeng, Zhi; Zhang, Yin; Chen, Wen; Roehling, Tien Tran; Ott, Ryan T.; Santala, Melissa K.; Depond, Philip J.; Matthews, Manyalibo J.; Hamza, Alex V.; Zhu, Ting

    2018-01-01

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength-ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearly six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.

  3. Rheology of High-Melt-Strength Polypropylene for Additive Manufacturing

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Kamleitner, Florian; Jagenteufel, Ralf

    Acrylonitrile butadiene styrene (ABS) is a widely used material for additive manufacturing (AM) fused deposition modeling (FDM). The rheological properties of high-melt-strength polypropylene (HMS-PP) were compared to commercially available ABS 250 filament to study the possibility of using...

  4. Manufacturing Advantage: Why High-Performance Work Systems Pay Off.

    Science.gov (United States)

    Appelbaum, Eileen; Bailey, Thomas; Berg, Peter; Kalleberg, Arne L.

    A study examined the relationship between high-performance workplace practices and the performance of plants in the following manufacturing industries: steel, apparel, and medical electronic instruments and imaging. The multilevel research methodology combined the following data collection activities: (1) site visits; (2) collection of plant…

  5. Damage Analysis and Evaluation of High Strength Concrete Frame Based on Deformation-Energy Damage Model

    Directory of Open Access Journals (Sweden)

    Huang-bin Lin

    2015-01-01

    Full Text Available A new method of characterizing the damage of high strength concrete structures is presented, which is based on the deformation energy double parameters damage model and incorporates both of the main forms of damage by earthquakes: first time damage beyond destruction and energy consumption. Firstly, test data of high strength reinforced concrete (RC columns were evaluated. Then, the relationship between stiffness degradation, strength degradation, and ductility performance was obtained. And an expression for damage in terms of model parameters was determined, as well as the critical input data for the restoring force model to be used in analytical damage evaluation. Experimentally, the unloading stiffness was found to be related to the cycle number. Then, a correction for this changing was applied to better describe the unloading phenomenon and compensate for the shortcomings of structure elastic-plastic time history analysis. The above algorithm was embedded into an IDARC program. Finally, a case study of high strength RC multistory frames was presented. Under various seismic wave inputs, the structural damages were predicted. The damage model and correction algorithm of stiffness unloading were proved to be suitable and applicable in engineering design and damage evaluation of a high strength concrete structure.

  6. Development of High Temperature Capacitor Technology and Manufacturing Capability

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2011-05-15

    The goal of the Development of High Temperature Capacitor Technology and Manufacturing Capability program was to mature a production-ready supply chain for reliable 250°C FPE (fluorinated polyester) film capacitors by 2011. These high-temperature film capacitors enable both the down hole drilling and aerospace industries by enabling a variety of benefits including: - Deeper oil exploration in higher temperature and pressure environments - Enabling power electronic and control equipment to operate in higher temperature environments - Enabling reduced cooling requirements of electronics - Increasing reliability and life of capacitors operating below rated temperature - Enabling capacitors to handle higher electrical losses without overheating. The key challenges to bringing the FPE film capacitors to market have been manufacturing challenges including: - FPE Film is difficult to handle and wind, resulting in poor yields - Voltage breakdown strength decreases when the film is wound into capacitors (~70% decrease) - Encapsulation technologies must be improved to enable higher perature operation - Manufacturing and test cycle time is very long As a direct result of this program most of the manufacturing challenges have been met. The FPE film production metalization and winding yield has increased to over 82% from 70%, and the voltage breakdown strength of the wound capacitors has increased 270% to 189 V/μm. The high temperature packaging concepts are showing significant progress including promising results for lead attachments and hermetic packages at 200°C and non-hermetic packages at 250°C. Manufacturing and test cycle time will decrease as the market for FPE capacitors develops.

  7. The DARPA manufacturing initiative in high temperature superconductivity

    International Nuclear Information System (INIS)

    Adams, K.R.

    1989-01-01

    The Defense Advanced Research Projects Agency (DARPA) has a very aggressive Technology Base program in high temperature superconductivity. This program is expected to provide the basis for a specialized set of military products - passive microwave and millimeter wave devices - within the next three years. In order to get these high leverage products into military systems, a manufacturing base must be developed for HTSC components. A plan for DARPA in HTSC manufacturing is directly coupled with the ongoing DARPA materials and device oriented R and D program. In essence, this plan recommends a three phased effort: 1. Phase I (two years); Fund companies through R and D contracts for specialized HTSC components; prepare a detailed plan and develop an HTSC consortium. 2. Phase II (six years): Establish an HTSC Sematech initiative for electronic applications, including active devices. 3. Phase III (optional): Continue the HTSC Sematech with emphasis on high power applications

  8. Controlling high-throughput manufacturing at the nano-scale

    Science.gov (United States)

    Cooper, Khershed P.

    2013-09-01

    Interest in nano-scale manufacturing research and development is growing. The reason is to accelerate the translation of discoveries and inventions of nanoscience and nanotechnology into products that would benefit industry, economy and society. Ongoing research in nanomanufacturing is focused primarily on developing novel nanofabrication techniques for a variety of applications—materials, energy, electronics, photonics, biomedical, etc. Our goal is to foster the development of high-throughput methods of fabricating nano-enabled products. Large-area parallel processing and highspeed continuous processing are high-throughput means for mass production. An example of large-area processing is step-and-repeat nanoimprinting, by which nanostructures are reproduced again and again over a large area, such as a 12 in wafer. Roll-to-roll processing is an example of continuous processing, by which it is possible to print and imprint multi-level nanostructures and nanodevices on a moving flexible substrate. The big pay-off is high-volume production and low unit cost. However, the anticipated cost benefits can only be realized if the increased production rate is accompanied by high yields of high quality products. To ensure product quality, we need to design and construct manufacturing systems such that the processes can be closely monitored and controlled. One approach is to bring cyber-physical systems (CPS) concepts to nanomanufacturing. CPS involves the control of a physical system such as manufacturing through modeling, computation, communication and control. Such a closely coupled system will involve in-situ metrology and closed-loop control of the physical processes guided by physics-based models and driven by appropriate instrumentation, sensing and actuation. This paper will discuss these ideas in the context of controlling high-throughput manufacturing at the nano-scale.

  9. Mining manufacturing data for discovery of high productivity process characteristics.

    Science.gov (United States)

    Charaniya, Salim; Le, Huong; Rangwala, Huzefa; Mills, Keri; Johnson, Kevin; Karypis, George; Hu, Wei-Shou

    2010-06-01

    Modern manufacturing facilities for bioproducts are highly automated with advanced process monitoring and data archiving systems. The time dynamics of hundreds of process parameters and outcome variables over a large number of production runs are archived in the data warehouse. This vast amount of data is a vital resource to comprehend the complex characteristics of bioprocesses and enhance production robustness. Cell culture process data from 108 'trains' comprising production as well as inoculum bioreactors from Genentech's manufacturing facility were investigated. Each run constitutes over one-hundred on-line and off-line temporal parameters. A kernel-based approach combined with a maximum margin-based support vector regression algorithm was used to integrate all the process parameters and develop predictive models for a key cell culture performance parameter. The model was also used to identify and rank process parameters according to their relevance in predicting process outcome. Evaluation of cell culture stage-specific models indicates that production performance can be reliably predicted days prior to harvest. Strong associations between several temporal parameters at various manufacturing stages and final process outcome were uncovered. This model-based data mining represents an important step forward in establishing a process data-driven knowledge discovery in bioprocesses. Implementation of this methodology on the manufacturing floor can facilitate a real-time decision making process and thereby improve the robustness of large scale bioprocesses. 2010 Elsevier B.V. All rights reserved.

  10. New high-precision deep concave optical surface manufacturing capability

    Science.gov (United States)

    Piché, François; Maloney, Chris; VanKerkhove, Steve; Supranowicz, Chris; Dumas, Paul; Donohue, Keith

    2017-10-01

    This paper describes the manufacturing steps necessary to manufacture hemispherical concave aspheric mirrors for high- NA systems. The process chain is considered from generation to final figuring and includes metrology testing during the various manufacturing steps. Corning Incorporated has developed this process by taking advantage of recent advances in commercially available Satisloh and QED Technologies equipment. Results are presented on a 100 mm concave radius nearly hemispherical (NA = 0.94) fused silica sphere with a better than 5 nm RMS figure. Part interferometric metrology was obtained on a QED stitching interferometer. Final figure was made possible by the implementation of a high-NA rotational MRF mode recently developed by QED Technologies which is used at Corning Incorporated for production. We also present results from a 75 mm concave radius (NA = 0.88) Corning ULE sphere that was produced using sub-aperture tools from generation to final figuring. This part demonstrates the production chain from blank to finished optics for high-NA concave asphere.

  11. Development of damage functions for high-rise building components

    International Nuclear Information System (INIS)

    Kustu, O.; Miller, D.D.; Brokken, S.T.

    1982-10-01

    The component approach for predicting the effects that ground motion from underground nuclear explosions will have on structures involves predicting the damage to each structural and nonstructural component of a building on the basis of the expected local deformation that most affects the damage to the component. This study was conducted to provide the basic data necessary to evaluate the component approach. Available published laboratory test data for various high-rise building components were collected. These data were analyzed statistically to determine damage threshold values and their variabilities, which in turn were used to derive component damage functions. The portion of construction costs attributable to various building components was determined statistically. This information was needed because component damage functions define damage as a percentage of the replacement values of the component, and, in order to calculate the overall building damage factor, the relative cost of each component must be estimated. The feasibility of the component approach to damage prediction is demonstrated. It is recommended that further experimental research directed towards developing an adequate data base of component damage thresholds for all significant building components should be encouraged. Parallel to this effort, detailed damage data from specific buildings damaged in earthquakes should be collected to verify the theoretical procedure

  12. High temperature damage of a re-sulfurized stainless steel

    International Nuclear Information System (INIS)

    Tinet, Hougo

    2002-01-01

    After having evoked the industrial problem raised by high-temperature damage in the 303 stainless steel, and outlined that the experimental study of high-temperature damage implies the study of the sane (or non damaged) material, the study of micro-voids germination, growth and coalescence, and the study of the material failure process, the author of this research thesis reports a bibliographical study on the behaviour of sane re-sulfurized stainless steel and different damage models. He presents experimental techniques (thermal-mechanical compression and tensile tests, image analysis in optical microscopy) which have been used in this work, and describes and comments results obtained on axisymmetric samples for micro-void germination, growth and coalescence in case of a damage under low and medium stress triaxiality. The last part addresses the study of the damage of strongly notched samples (stress triaxialities close to those existing at the crack bottom) [fr

  13. Carbon-carbon composite and copper-composite bond damages for high flux component controlled fusion

    International Nuclear Information System (INIS)

    Chevet, G.

    2010-01-01

    Plasma facing components constitute the first wall in contact with plasma in fusion machines such as Tore Supra and ITER. These components have to sustain high heat flux and consequently elevated temperatures. They are made up of an armour material, the carbon-carbon composite, a heat sink structure material, the copper chromium zirconium, and a material, the OFHC copper, which is used as a compliant layer between the carbon-carbon composite and the copper chromium zirconium. Using different materials leads to the apparition of strong residual stresses during manufacturing, because of the thermal expansion mismatch between the materials, and compromises the lasting operation of fusion machines as damage which appeared during manufacturing may propagate. The objective of this study is to understand the damage mechanisms of the carbon-carbon composite and the composite-copper bond under solicitations that plasma facing components may suffer during their life. The mechanical behaviours of carbon-carbon composite and composite-copper bond were studied in order to define the most suitable models to describe these behaviours. With these models, thermomechanical calculations were performed on plasma facing components with the finite element code Cast3M. The manufacturing of the components induces high stresses which damage the carbon-carbon composite and the composite-copper bond. The damage propagates during the cooling down to room temperature and not under heat flux. Alternative geometries for the plasma facing components were studied to reduce damage. The relation between the damage of the carbon-carbon composite and its thermal conductivity was also demonstrated. (author) [fr

  14. Manufacture of sintered bricks of high density from beryllium oxide

    International Nuclear Information System (INIS)

    Pointud, R.; Rispal, Ch.; Le Garec, M.

    1959-01-01

    Beryllium oxide bricks of nuclear purity 100 x 100 x 50 and 100 x 100 x 100 mm of very high density (between 2.85 and 3.00) are manufactured by sintering under pressure in graphite moulds at temperatures between 1,750 and 1,850 deg. C, and under a pressure of 150 kg/cm 2 . The physico-chemical state of the saw material is of considerable importance with regard to the success of the sintering operation. In addition, a study of the sintering of a BeO mixture with 3 to 5 per cent of boron introduced in the form of boric acid, boron carbide or elementary boron shows that high densities can only be obtained by sintering under pressure. For technical reasons of manufacture, only the mixture based on boron carbide is used. The sintering is carried out in graphite moulds at 1500 deg. C under 150 kg/cm 2 pressure, and bricks can be obtained with density between 2,85 and 2,90. Laboratory studies and the industrial manufacture of various sinters are described in detail. (author) [fr

  15. Automated Manufacture of Damage Detecting, Self-Healing Composite Cryogenic Pressure Vessels, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — After successfully demonstrating the basic functionality of a damage-detecting, self-healing 'smart' material system in Phase I, Aurora and UMass Lowell aim to...

  16. Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

    International Nuclear Information System (INIS)

    Souza, J.A.B.; Durazzo, M.

    2010-01-01

    IPEN developed and made available for routine production the technology for manufacturing dispersion type fuel elements for use in research reactors. However, the fuel produced at IPEN is limited to the uranium concentration of 3.0 gU/cm 3 by using the U 3 Si 2 -Al dispersion. Increasing the uranium concentration of the fuel is interesting by the possibility of increasing the reactor core reactivity and lifetime of the fuel. It is possible to increase the concentration of uranium in the fuel up to the technological limit of 4.8 gU/cm 3 for the U 3 Si 2 -Al dispersion, which is well placed around the world. This new fuel will be applicable in the new Brazilian-Multipurpose Reactor RMB. This study aimed to develop the manufacturing process of high uranium concentration fuel, redefining the procedures currently used in the manufacture of IPEN. This paper describes the main procedures adjustments that will be necessary. (author)

  17. Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Jose Antonio Batista de; Durazzo, Michelangelo, E-mail: jasouza@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    IPEN developed and made available for routine production the technology for manufacturing dispersion type fuel elements for use in research reactors. However, the fuel produced at IPEN is limited to the uranium concentration of 3.0 g U/c m3 by using the U{sub 3}Si{sub 2}-Al dispersion. Increasing the uranium concentration of the fuel is interesting by the possibility of increasing the reactor core reactivity and lifetime of the fuel. It is possible to increase the concentration of uranium in the fuel up to the technological limit of 4.8 g U/c m3 for the U{sub 3}Si{sub 2}-Al dispersion, which is well placed around the world. This new fuel will be applicable in the new Brazilian- Multipurpose Reactor RMB. This study aimed to develop the manufacturing process of high uranium concentration fuel, redefining the procedures currently used in the manufacture of IPEN. This paper describes the main procedures adjustments that will be necessary. (author)

  18. High Volume Manufacturing and Field Stability of MEMS Products

    Science.gov (United States)

    Martin, Jack

    Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are

  19. Design of a high pulse repitition frequency carbon dioxide laser for processing high damage threshold materials

    Science.gov (United States)

    Chatwin, Christopher R.; McDonald, Donald W.; Scott, Brian F.

    1989-07-01

    The absence of an applications led design philosophy has compromised both the development of laser source technology and its effective implementation into manufacturing technology in particular. For example, CO2 lasers are still incapable of processing classes of refractory and non-ferrous metals. Whilst the scope of this paper is restricted to high power CO2 lasers; the design methodology reported herein is applicable to source technology in general, which when exploited, will effect an expansion of applications. The CO2 laser operational envelope should not only be expanded to incorporate high damage threshold materials but also offer a greater degree of controllability. By a combination of modelling and experimentation the requisite beam characteristics, at the workpiece, were determined then utilised to design the Laser Manufacturing System. The design of sub-system elements was achieved by a combination of experimentation and simulation which benefited from a comprehensive set of software tools. By linking these tools the physical processes in the laser - electron processes in the plasma, the history of photons in the resonator, etc. - can be related, in a detailed model, to the heating mechanisms in the workpiece.

  20. Mechanically recovered poultry meat sausages manufactured with high hydrostatic pressure.

    Science.gov (United States)

    Yuste, J; Mor-Mur, M; Capellas, M; Guamis, B; Pla, R

    1999-06-01

    The effect of high pressure processing at high temperature on texture and color of frankfurter-type sausages made with different contents of mechanically recovered poultry meat (MRPM) was evaluated and compared with that of a standard cooking process. Five types of sausages containing 100, 75, 50, 25, and 0% MRPM and 0, 25, 50, 75, and 100% of minced pork meat (MPM), respectively, were manufactured. They were pressurized at 500 MPa for 30 min at 50, 60, 70, and 75 C or cooked at 75 C for 30 min. Pressure-treated sausages were less springy and firm, but more cohesive. Moreover, color of pressurized sausages was lighter and more yellow than that of conventionally cooked sausages. Addition of MPM increased cohesiveness, hardness, and force at 80% compression. Minced pork meat also caused the appearance of sausages to be lighter, less red, and less yellow. Cooked sausages made with MRPM can have an attractive appearance and texture via high pressure processing.

  1. High strength fused silica flexures manufactured by femtosecond laser

    Science.gov (United States)

    Bellouard, Yves; Said, Ali A.; Dugan, Mark; Bado, Philippe

    2009-02-01

    Flexures are mechanical elements used in micro- and precision-engineering to precisely guide the motion of micro-parts. They consist of slender bodies that deform elastically upon the application of a force. Although counter-intuitive at first, fused silica is an attractive material for flexure. Pending that the machining process does not introduce surface flaws that would lead to catastrophic failure, the material has a theoretically high ultimate tensile strength of several GPa. We report on high-aspect ratio fused silica flexures manufactured by femtosecond laser combined with chemical etching. Notch-hinges with thickness as small as twenty microns and aspect ratios comparable to aspect ratios obtained by Deep- Reactive-Ion-Etching (DRIE) were fabricated and tested under different loading conditions. Multiple fracture tests were performed for various loading conditions and the cracks morphologies were analyzed using Scanning Electron Microscopy. The manufactured elements show outstanding mechanical properties with flexural strengths largely exceeding those obtained with other technologies and materials. Fused silica flexures offer a mean to combine integrated optics with micro-mechanics in a single monolithic substrate. Waveguides and mechanical elements can be combined in a monolithic devices opening new opportunities for integrated opto-mechatronics devices.

  2. Fibrous Fillers to Manufacture Ultra High Ash/Performance Paper

    Energy Technology Data Exchange (ETDEWEB)

    Dr. VIjay K. Mathur

    2009-04-30

    The paper industry is one of the largest users of energy and emitters of CO2 in the US manufacturing industry. In addition to that, it is facing tremendous financial pressure due to lower cost imports. The fine paper industry has shrunk from 15 million tons per year production to 10 million tons per year in the last 5 years. This has resulted in mill closures and job loses. The AF&PA and the DOE formed a program called Agenda 2020 to help in funding to develop breakthrough technologies to provide help in meeting these challenges. The objectives of this project were to optimize and scale-up Fibrous Fillers technology, ready for commercial deployment and to develop ultra high ash/high performance paper using Fibrous Fillers. The goal was to reduce energy consumption, carbon footprint, and cost of manufacturing paper and related industries. GRI International (GRI) has been able to demonstrate the techno - economic feasibility and economic advantages of using its various products in both handsheets as well as in commercial paper mills. GRI has also been able to develop sophisticated models that demonstrate the effect of combinations of GRI's fillers at multiple filler levels. GRI has also been able to develop, optimize, and successfully scale-up new products for use in commercial paper mills.

  3. Intelligent technologies in process of highly-precise products manufacturing

    Science.gov (United States)

    Vakhidova, K. L.; Khakimov, Z. L.; Isaeva, M. R.; Shukhin, V. V.; Labazanov, M. A.; Ignatiev, S. A.

    2017-10-01

    One of the main control methods of the surface layer of bearing parts is the eddy current testing method. Surface layer defects of bearing parts, like burns, cracks and some others, are reflected in the results of the rolling surfaces scan. The previously developed method for detecting defects from the image of the raceway was quite effective, but the processing algorithm is complicated and lasts for about 12 ... 16 s. The real non-stationary signals from an eddy current transducer (ECT) consist of short-time high-frequency and long-time low-frequency components, therefore a transformation is used for their analysis, which provides different windows for different frequencies. The wavelet transform meets these conditions. Based on aforesaid, a methodology for automatically detecting and recognizing local defects in bearing parts surface layer has been developed on the basis of wavelet analysis using integral estimates. Some of the defects are recognized by the amplitude component, otherwise an automatic transition to recognition by the phase component of information signals (IS) is carried out. The use of intelligent technologies in the manufacture of bearing parts will, firstly, significantly improve the quality of bearings, and secondly, significantly improve production efficiency by reducing (eliminating) rejections in the manufacture of products, increasing the period of normal operation of the technological equipment (inter-adjustment period), the implementation of the system of Flexible facilities maintenance, as well as reducing production costs.

  4. High LET radiation and mechanism of DNA damage repair

    International Nuclear Information System (INIS)

    Furusawa, Yoshiya

    2004-01-01

    Clarifying the mechanism of repair from radiation damage gives most important information on radiation effects on cells. Approximately 10% of biological experiments groups in Heavy Ion Medical Accelerator in Chiba (HIMAC) cooperative research group has performed the subject. They gave a lot of new findings on the mechanism, and solved some open questions. The reason to show the peak of relative biological effectiveness RBE at around 100-200 keV/μm causes miss-repair of DNA damage. Sub-lethal damage generated by high linear energy transfer (LET) radiation can be repaired fully. Potentially lethal damages by high-LET radiation also repaired, but the efficiency decreased with the LET, and so on. (author)

  5. High-Damage-Threshold Pinhole for Glass Fusion Laser Applications

    International Nuclear Information System (INIS)

    Kumit, N.A.; Letzring, S.A.; Johnson, R.P.

    1998-01-01

    We are investigating methods to fabricate high-damage-threshold spatial-filter pinholes that might not be susceptible to plasma closure for relatively high energies and long pulses. These are based on the observation that grazing-incidence reflection from glass can withstand in excess of 5 kJ/cm 2 (normal to the beam) without plasma formation. The high damage threshold results from both the cos q spreading of the energy across the surface and the reflection of a large fraction of the energy from the surface, thereby greatly reducing the field strength within the medium

  6. Radiation damage in molybdenum and tungsten in high neutron fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Veljkovic, S; Milasin, N [Institute of Nuclear Sciences Boris Kidric, Department of Reactor Materials, Vinca, Beograd (Serbia and Montenegro)

    1964-04-15

    The effects of radiation on molybdenum and tungsten in high neutron fluxes are presented. The changes induced, particularly defects with a high migration activation energy, are analyzed. The correlation of these changes with the basic concepts of radiation damage in solids is considered. An attempt is made to relate the defects studied with the changes in macroscopic properties (author)

  7. Radiation damage in molybdenum and tungsten in high neutron fluxes

    International Nuclear Information System (INIS)

    Veljkovic, S.; Milasin, N.

    1964-01-01

    The effects of radiation on molybdenum and tungsten in high neutron fluxes are presented. The changes induced, particularly defects with a high migration activation energy, are analyzed. The correlation of these changes with the basic concepts of radiation damage in solids is considered. An attempt is made to relate the defects studied with the changes in macroscopic properties (author)

  8. Elevated Temperature, Residual Compressive Strength of Impact-Damaged Sandwich Structure Manufactured Out-of-Autoclave

    Science.gov (United States)

    Grimsley, Brian W.; Sutter, James K.; Burke, Eric R.; Dixon, Genevieve D.; Gyekenyesi, Thomas G.; Smeltzer, Stanley S.

    2012-01-01

    Several 1/16th-scale curved sandwich composite panel sections of a 10 m diameter barrel were fabricated to demonstrate the manufacturability of large-scale curved sections using minimum gauge, [+60/-60/0]s, toughened epoxy composite facesheets co-cured with low density (50 kilograms per cubic meters) aluminum honeycomb core. One of these panels was fabricated out of autoclave (OoA) by the vacuum bag oven (VBO) process using Cycom(Registered Trademark) T40-800b/5320-1 prepreg system while another panel with the same lay-up and dimensions was fabricated using the autoclave-cure, toughened epoxy prepreg system Cycom(Registered Trademark) IM7/977-3. The resulting 2.44 m x 2 m curved panels were investigated by non-destructive evaluation (NDE) at NASA Langley Research Center (NASA LaRC) to determine initial fabrication quality and then cut into smaller coupons for elevated temperature wet (ETW) mechanical property characterization. Mechanical property characterization of the sandwich coupons was conducted including edge-wise compression (EWC), and compression-after-impact (CAI) at conditions ranging from 25 C/dry to 150 C/wet. The details and results of this characterization effort are presented in this paper.

  9. Seismic damage assessment for high-rise buildings

    Science.gov (United States)

    Scholl, Roger E.

    1980-01-01

    The problem considered in this project, conducted by URS/John A. Blume & Associates, Engineers (URS/Blume), for the U.S. Geological Survey, is the identification, evaluation, and correlation of ground-motion and structural parameters in order to improve procedures for predicting dollar losses for high-rise structures damaged by earthquakes. Ground-motion data bases, analytical techniques, and known motion-damage relationships already developed for high-rise buildings and for other classes of structures will be refined and extended so that reliable quantitative seismic risk evaluations can be made.

  10. Large-aperture, high-damage-threshold optics for beamlet

    International Nuclear Information System (INIS)

    Campbell, J.H.; Atherton, L.J.; DeYoreo, J.J.; Kozlowski, M.R.; Maney, R.T.; Montesanti, R.C.; Sheehan, L.M.; Barker, C.E.

    1995-01-01

    Beamlet serves as a test bed for the proposed NIF laser design and components. Therefore, its optics are similar in size and quality to those proposed for the NIF. In general, the optics in the main laser cavity and transport section of Beamlet are larger and have higher damage thresholds than the optics manufactured for any of our previous laser systems. In addition, the quality of the Beamlet optical materials is higher, leading to better wavefront quality, higher optical transmission, and lower-intensity modulation of the output laser beam than, for example, that typically achieved on Nova. In this article, we discuss the properties and characteristics of the large-aperture optics used on Beamlet

  11. Multiscale Modeling of Dewetting Damage in Highly Filled Particulate Composites

    Science.gov (United States)

    Geubelle, P. H.; Inglis, H. M.; Kramer, J. D.; Patel, J. J.; Kumar, N. C.; Tan, H.

    2008-02-01

    Particle debonding or dewetting constitutes one of the key damage processes in highly filled particulate composites such as solid propellant and other energetic materials. To analyze this failure process, we have developed a multiscale finite element framework that combines, at the microscale, a nonlinear description of the binder response with a cohesive model of the damage process taking place in a representative periodic unit cell (PUC). To relate micro-scale damage to the macroscopic constitutive response of the material, we employ the mathematical theory of homogenization (MTH). After a description of the numerical scheme, we present the results of the damage response of a highly filled particulate composite subjected to a uniaxial macroscopic strain, and show the direct correlation between the complex damage processes taking place in the PUC and the nonlinear macroscopic constitutive response. We also present a detailed study of the PUC size and a comparison between the finite element MTH-based study and a micromechanics model of the dewetting process.

  12. Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

    International Nuclear Information System (INIS)

    Souza, Jose Antonio Batista de

    2011-01-01

    IPEN-CNEN/SP developed the technology to produce the dispersion type fuel elements for research reactors and made it available for routine production. Today, the fuel produced in IPEN-CNEN/SP is limited to the uranium concentration of 3.0 gU/cm 3 for U 3 Si 2 -Al dispersion-based and 2.3 gU/cm 3 for U 3 O 8 -Al dispersion. The increase of uranium concentration in fuel plates enables the reactivity of the reactor core reactivity to be higher and extends the fuel life. Concerning technology, it is possible to increase the uranium concentration in the fuel meat up to the limit of 4.8 gU/cm 3 in U 3 Si 2 -Al dispersion and 3.2 gU/cm 3 U 3 O 8 -Al dispersion. These dispersions are well qualified worldwide. This work aims to develop the manufacturing process of both fuel meats with high uranium concentrations, by redefining the manufacturing procedures currently adopted in the Nuclear Fuel Center of IPEN-CNEN/SP. Based on the results, it was concluded that to achieve the desired concentration, it is necessary to make some changes in the established procedures, such as in the particle size of the fuel powder and in the feeding process inside the matrix, before briquette pressing. These studies have also shown that the fuel plates, with a high concentration of U 3 Si 2 -Al, met the used specifications. On the other hand, the appearance of the microstructure obtained from U 3 O 8 -Al dispersion fuel plates with 3.2 gU/cm 3 showed to be unsatisfactory, due to the considerably significant porosity observed. The developed fabrication procedure was applied to U 3 Si 2 production at 4.8 gU/cm 3 , with enriched uranium. The produced plates were used to assemble the fuel element IEA-228, which was irradiated in order to check its performance in the IEA-R1 reactor at IPEN-CNEN/SP. These new fuels have potential to be used in the new Brazilian Multipurpose Reactor - RMB. (author)

  13. Integrated design and manufacturing for the high speed civil transport

    Science.gov (United States)

    1993-01-01

    In June 1992, Georgia Tech's School of Aerospace Engineering was awarded a NASA University Space Research Association (USRA) Advanced Design Program (ADP) to address 'Integrated Design and Manufacturing for the High Speed Civil Transport (HSCT)' in its graduate aerospace systems design courses. This report summarizes the results of the five courses incorporated into the Georgia Tech's USRA ADP program. It covers AE8113: Introduction to Concurrent Engineering, AE4360: Introduction to CAE/CAD, AE4353: Design for Life Cycle Cost, AE6351: Aerospace Systems Design One, and AE6352: Aerospace Systems Design Two. AE8113: Introduction to Concurrent Engineering was an introductory course addressing the basic principles of concurrent engineering (CE) or integrated product development (IPD). The design of a total system was not the objective of this course. The goal was to understand and define the 'up-front' customer requirements, their decomposition, and determine the value objectives for a complex product, such as the high speed civil transport (HSCT). A generic CE methodology developed at Georgia Tech was used for this purpose. AE4353: Design for Life Cycle Cost addressed the basic economic issues for an HSCT using a robust design technique, Taguchi's parameter design optimization method (PDOM). An HSCT economic sensitivity assessment was conducted using a Taguchi PDOM approach to address the robustness of the basic HSCT design. AE4360: Introduction to CAE/CAD permitted students to develop and utilize CAE/CAD/CAM knowledge and skills using CATIA and CADAM as the basic geometric tools. AE6351: Aerospace Systems Design One focused on the conceptual design refinement of a baseline HSCT configuration as defined by Boeing, Douglas, and NASA in their system studies. It required the use of NASA's synthesis codes FLOPS and ACSYNT. A criterion called the productivity index (P.I.) was used to evaluate disciplinary sensitivities and provide refinements of the baseline HSCT

  14. High-speed, low-damage grinding of advanced ceramics Phase 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kovach, J.A. [Eaton Corp., Willoughby Hills, OH (United States). Mfg. Technologies Center; Malkin, S. [Univ. of Massachusetts (United States)

    1995-03-01

    In manufacture of structural ceramic components, grinding costs can comprise up to 80% of the entire manufacturing cost. Most of these costs arise from the conventional multi-step grinding process with numerous grinding wheels and additional capital equipment, perishable dressing tools, and labor. In an attempt to reduce structural ceramic grinding costs, a feasibility investigation was undertaken to develop a single step, roughing-finishing process suitable for producing high-quality silicon nitride ceramic parts at high material removal rates at lower cost than traditional, multi-stage grinding. This feasibility study employed combined use of laboratory grinding tests, mathematical grinding models, and characterization of resultant material surface condition. More specifically, this Phase 1 final report provides a technical overview of High-Speed, Low-Damage (HSLD) ceramic grinding and the conditions necessary to achieve the small grain depths of cut necessary for low damage grinding while operating at relatively high material removal rates. Particular issues addressed include determining effects of wheel speed and material removal rate on resulting mode of material removal (ductile or brittle fracture), limiting grinding forces, calculation of approximate grinding zone temperatures developed during HSLD grinding, and developing the experimental systems necessary for determining HSLD grinding energy partition relationships. In addition, practical considerations for production utilization of the HSLD process are also discussed.

  15. Bottom Raking Damage to High-Speed Craft

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1998-01-01

    This paper presents a comparative study of the raking damage to high speed craft (HSC) and conventional ships. The analysis is based on a detailed theoretical model for the raking resistance of an assembled ship bottom structure and on the idea that the impact conditions for various ship types have...

  16. Techniques for preventing damage to high power laser components

    International Nuclear Information System (INIS)

    Stowers, I.F.; Patton, H.G.; Jones, W.A.; Wentworth, D.E.

    1977-09-01

    Techniques for preventing damage to components of the LASL Shiva high power laser system were briefly presented. Optical element damage in the disk amplifier from the combined fluence of the primary laser beam and the Xenon flash lamps that pump the cavity was discussed. Assembly and cleaning techniques were described which have improved optical element life by minimizing particulate and optically absorbing film contamination on assembled amplifier structures. A Class-100 vertical flaw clean room used for assembly and inspection of laser components was also described. The life of a disk amplifier was extended from less than 50 shots to 500 shots through application of these assembly and cleaning techniques

  17. EUV source development for high-volume chip manufacturing tools

    Science.gov (United States)

    Stamm, Uwe; Yoshioka, Masaki; Kleinschmidt, Jürgen; Ziener, Christian; Schriever, Guido; Schürmann, Max C.; Hergenhan, Guido; Borisov, Vladimir M.

    2007-03-01

    Xenon-fueled gas discharge produced plasma (DPP) sources were integrated into Micro Exposure Tools already in 2004. Operation of these tools in a research environment gave early learning for the development of EUV sources for Alpha and Beta-Tools. Further experiments with these sources were performed for basic understanding on EUV source technology and limits, especially the achievable power and reliability. The intermediate focus power of Alpha-Tool sources under development is measured to values above 10 W. Debris mitigation schemes were successfully integrated into the sources leading to reasonable collector mirror lifetimes with target of 10 billion pulses due to the effective debris flux reduction. Source collector mirrors, which withstand the radiation and temperature load of Xenon-fueled sources, have been developed in cooperation with MediaLario Technologies to support intermediate focus power well above 10 W. To fulfill the requirements for High Volume chip Manufacturing (HVM) applications, a new concept for HVM EUV sources with higher efficiency has been developed at XTREME technologies. The discharge produced plasma (DPP) source concept combines the use of rotating disk electrodes (RDE) with laser exited droplet targets. The source concept is called laser assisted droplet RDE source. The fuel of these sources has been selected to be Tin. The conversion efficiency achieved with the laser assisted droplet RDE source is 2-3x higher compared to Xenon. Very high pulse energies well above 200 mJ / 2π sr have been measured with first prototypes of the laser assisted droplet RDE source. If it is possible to maintain these high pulse energies at higher repetition rates a 10 kHz EUV source could deliver 2000 W / 2π sr. According to the first experimental data the new concept is expected to be scalable to an intermediate focus power on the 300 W level.

  18. Ultrasonic Additive Manufacturing for High Performance Combustion Chambers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to demonstrate the feasibility of using ultrasonic additive manufacturing (UAM) to dramatically reduce the cost and lead-time of...

  19. Micro-damage propagation in ultra-high vacuum seals

    CERN Document Server

    Lutkiewicz, P; Garion, C

    2010-01-01

    The paper addresses a fundamental problem of tightness of ultra-high vacuum systems (UHV) at cryogenic temperatures in the light of continuum damage mechanics (CDM). The problem of indentation of a rigid punch into an elastic-plastic half-space is investigated based on rate independent plasticity with mixed kinematic and isotropic hardening. The micro-damage fields are modeled by using an anisotropic approach with a kinetic law of damage evolution suitable for ductile materials and cryogenic temperatures. The model has been experimentally validated and the results are used to predict the onset of macro-cracking (loss of tightness) and the corresponding load (contact pressure). The algorithm is applied in the design of UHV systems for particle accelerators. (C) 2009 Published by Elsevier Ltd.

  20. Design of novel materials for additive manufacturing - Isotropic microstructure and high defect tolerance.

    Science.gov (United States)

    Günther, J; Brenne, F; Droste, M; Wendler, M; Volkova, O; Biermann, H; Niendorf, T

    2018-01-22

    Electron Beam Melting (EBM) is a powder-bed additive manufacturing technology enabling the production of complex metallic parts with generally good mechanical properties. However, the performance of powder-bed based additively manufactured materials is governed by multiple factors that are difficult to control. Alloys that solidify in cubic crystal structures are usually affected by strong anisotropy due to the formation of columnar grains of preferred orientation. Moreover, processing induced defects and porosity detrimentally influence static and cyclic mechanical properties. The current study presents results on processing of a metastable austenitic CrMnNi steel by EBM. Due to multiple phase transformations induced by intrinsic heat-treatment in the layer-wise EBM process the material develops a fine-grained microstructure almost without a preferred crystallographic grain orientation. The deformation-induced phase transformation yields high damage tolerance and, thus, excellent mechanical properties less sensitive to process-induced inhomogeneities. Various scan strategies were applied to evaluate the width of an appropriate process window in terms of microstructure evolution, porosity and change of chemical composition.

  1. Innovative Processing Methods for the Affordable Manufacture of Multifunctional High Temperature Coatings, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Research is proposed to investigate the feasibility of using advanced manufacturing techniques to enable the affordable application of multi-functional high...

  2. The Development of High Temperature Thermoplastic Composite Materials for Additive Manufactured Autoclave Tooling

    Energy Technology Data Exchange (ETDEWEB)

    Kunc, Vlastimil [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Duty, Chad E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lindahl, John M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hassen, Ahmed A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    In this work, ORNL and Techmer investigated and screened different high temperature thermoplastic reinforced materials to fabricate composite molds for autoclave processes using Additive Manufacturing (AM) techniques. This project directly led to the development and commercial release of two printable, high temperature composite materials available through Techmer PM. These new materials are targeted for high temperature tooling made via large scale additive manufacturing.

  3. Manufacturing of ultra high vacuum compatible accelerator and laser components

    International Nuclear Information System (INIS)

    Mundra, G.; Sharma, S.D.; Bhatnagar, V.

    2015-01-01

    For carrying out advanced basic research, Raja Ramanna Centre for Advanced Technology, (RRCAT) had set up 450 MeV and 2.5 GeV Synchrotron Radiation Sources. Many beamlines are being utilized by researchers from various universities and institutions of the country. Centre has also developed various lasers that find application in various front line areas like medicine, industry and research. To cater the need of manufacturing for these programs, an advanced and versatile manufacturing development center was established, called Accelerator Components Design and Fabrication Section (ACDFS),

  4. Rheology of high melt strength polypropylene for additive manufacturing

    DEFF Research Database (Denmark)

    Jagenteufel, Ralf; Hofstätter, Thomas; Kamleitner, Florian

    2017-01-01

    stability, whereas HMS-PP showed a more stable behavior at the investigated temperatures. Hereafter, the material was used in a fused deposition modeling additive manufacturing process, focusing on the investigation of possible improvements of HMS-PP over ABS. Based on the extrusion parameters for ABS...

  5. Damage detection in high-rise buildings using damage-induced rotations

    International Nuclear Information System (INIS)

    Sung, Seung Hun; Jung, Ho Youn; Lee, Jung Hoon; Jung, Hyung Jo

    2016-01-01

    In this paper, a new damage-detection method based on structural vibration is proposed. The essence of the proposed method is the detection of abrupt changes in rotation. Damage-induced rotation (DIR), which is determined from the modal flexibility of the structure, initially occurs only at a specific damaged location. Therefore, damage can be localized by evaluating abrupt changes in rotation. We conducted numerical simulations of two damage scenarios using a 10-story cantilever-type building model. Measurement noise was also considered in the simulation. We compared the sensitivity of the proposed method to localize damage to that of two conventional modal-flexibility-based damage-detection methods, i.e., uniform load surface (ULS) and ULS curvature. The proposed method was able to localize damage in both damage scenarios for cantilever structures, but the conventional methods could not

  6. Damage detection in high-rise buildings using damage-induced rotations

    International Nuclear Information System (INIS)

    Sung, Seung Hoon; Jung, Ho Youn; Lee, Jung Hoon; Jung, Hyung Jo

    2014-01-01

    In this paper, a new damage-detection method based on structural vibration is proposed. The essence of the proposed method is the detection of abrupt changes in rotation. Damage-induced rotation (DIR), which is determined from the modal flexibility of the structure, initially occurs only at a specific damaged location. Therefore, damage can be localized by evaluating abrupt changes in rotation. We conducted numerical simulations of two damage scenarios using a 10-story cantilever-type building model. Measurement noise was also considered in the simulation. We compared the sensitivity of the proposed method to localize damage to that of two conventional modal-flexibility-based damage-detection methods, i.e., uniform load surface (ULS) and ULS curvature. The proposed method was able to localize damage in both damage scenarios for cantilever structures, but the conventional methods could not.

  7. Quality Improvement, Inventory Management, Lead Time Reduction and Production Scheduling in High-Mix Manufacturing Environments

    Science.gov (United States)

    2017-01-13

    Quality Improvement , Inventory Management, Lead Time Reduction and Production Scheduling in High-mix Manufacturing Environments by Sean Daigle B.S...Mechanical Engineering Chairman, Department Committee on Graduate Theses 2 Quality Improvement , Inventory Management, Lead Time Reduction and... Production Scheduling in High-mix Manufacturing Environments by Sean Daigle Submitted to the Department of Mechanical Engineering on January 13, 2017, in

  8. The influence of cellular structures on flow stress of high strength components manufactured using SLM

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans Nørgaard; Loft Højbjerre, Klaus

    2016-01-01

    Additive manufacturing has shown significant improvement in material and machines for high-quality solid freeform fabrication processes such as selective laser melting (SLM). In particular, manufacturing lattice structures using the SLM procedure is of interest. This research examines the effect...... of cellular materials on compression strength. The specimens are manufactured additively using industrial 3D printing systems from high-strength alloy. The material has the right mechanical properties for manufacturing tool components. This includes samples with solid and lattice structures. The Compression...

  9. Surface damage characterization of FBK devices for High Luminosity LHC (HL-LHC) operations

    Science.gov (United States)

    Moscatelli, F.; Passeri, D.; Morozzi, A.; Dalla Betta, G.-F.; Mattiazzo, S.; Bomben, M.; Bilei, G. M.

    2017-12-01

    The very high fluences (e.g. up to 2×1016 1 MeV neq/cm2) and total ionising doses (TID) of the order of 1 Grad, expected at the High Luminosity LHC (HL-LHC), impose new challenges for the design of effective, radiation resistant detectors. Ionising energy loss is the dominant effect for what concerns SiO2 and SiO2/Si interface radiation damage. In particular, surface damage can create a positive charge layer near the SiO2/Si interface and interface traps along the SiO2/Si interface, which strongly influence the breakdown voltage, the inter-electrode isolation and capacitance, and might also impact the charge collection properties of silicon sensors. To better understand in a comprehensive framework the complex and articulated phenomena related to surface damage at these very high doses, measurements on test structures have been carried out in this work (e.g. C-V and I-V). In particular, we have studied the properties of the SiO2 layer and of the SiO2/Si interface, using MOS capacitors, gated diodes (GD) and MOSFETs manufactured by FBK on high-resistivity n-type and p-type silicon, before and after irradiation with X-rays in the range from 50 krad(SiO2) to 20 Mrad(SiO2). Relevant parameters have been determined for all the tested devices, converging in the oxide charge density NOX, the surface generation velocity s0 and the integrated interface-trap density NIT dose-dependent values. These parameters have been extracted to both characterize the technology as a function of the dose and to be used in TCAD simulations for the surface damage effect modeling and the analysis and optimization of different classes of detectors for the next HEP experiments.

  10. Manufacturing High-Quality Carbon Nanotubes at Lower Cost

    Science.gov (United States)

    Benavides, Jeanette M.; Lidecker, Henning

    2004-01-01

    A modified electric-arc welding process has been developed for manufacturing high-quality batches of carbon nanotubes at relatively low cost. Unlike in some other processes for making carbon nanotubes, metal catalysts are not used and, consequently, it is not necessary to perform extensive cleaning and purification. Also, unlike some other processes, this process is carried out at atmospheric pressure under a hood instead of in a closed, pressurized chamber; as a result, the present process can be implemented more easily. Although the present welding-based process includes an electric arc, it differs from a prior electric-arc nanotube-production process. The welding equipment used in this process includes an AC/DC welding power source with an integral helium-gas delivery system and circulating water for cooling an assembly that holds one of the welding electrodes (in this case, the anode). The cathode is a hollow carbon (optionally, graphite) rod having an outside diameter of 2 in. (approximately equal to 5.1 cm) and an inside diameter of 5/8 in. (approximately equal to 1.6 cm). The cathode is partly immersed in a water bath, such that it protrudes about 2 in. (about 5.1 cm) above the surface of the water. The bottom end of the cathode is held underwater by a clamp, to which is connected the grounding cable of the welding power source. The anode is a carbon rod 1/8 in. (approximately equal to 0.3 cm) in diameter. The assembly that holds the anode includes a thumbknob- driven mechanism for controlling the height of the anode. A small hood is placed over the anode to direct a flow of helium downward from the anode to the cathode during the welding process. A bell-shaped exhaust hood collects the helium and other gases from the process. During the process, as the anode is consumed, the height of the anode is adjusted to maintain an anode-to-cathode gap of 1 mm. The arc-welding process is continued until the upper end of the anode has been lowered to a specified height

  11. System and method for high power diode based additive manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    El-Dasher, Bassem S.; Bayramian, Andrew; Demuth, James A.; Farmer, Joseph C.; Torres, Sharon G.

    2018-01-02

    A system is disclosed for performing an Additive Manufacturing (AM) fabrication process on a powdered material forming a substrate. The system may make use of a diode array for generating an optical signal sufficient to melt a powdered material of the substrate. A mask may be used for preventing a first predetermined portion of the optical signal from reaching the substrate, while allowing a second predetermined portion to reach the substrate. At least one processor may be used for controlling an output of the diode array.

  12. System and method for high power diode based additive manufacturing

    Science.gov (United States)

    El-Dasher, Bassem S.; Bayramian, Andrew; Demuth, James A.; Farmer, Joseph C.; Torres, Sharon G.

    2016-04-12

    A system is disclosed for performing an Additive Manufacturing (AM) fabrication process on a powdered material forming a substrate. The system may make use of a diode array for generating an optical signal sufficient to melt a powdered material of the substrate. A mask may be used for preventing a first predetermined portion of the optical signal from reaching the substrate, while allowing a second predetermined portion to reach the substrate. At least one processor may be used for controlling an output of the diode array.

  13. Proceedings of damage and oxidation protection in high temperature composites

    International Nuclear Information System (INIS)

    Haritos, G.K.; Ochoa, O.O.

    1991-01-01

    This book contains proceedings of Damage and Oxidation Protection in High Temperature Composites. Topics covered include: current issues in the development of new materials and structural concepts for the aerospace structures of the future; transportation vehicles of the future; materials and structural concepts; fundamental understanding and quantitative descriptions of the physical processes and mechanisms controlling the behavior of emerging materials and structures; and the critical need for advances in our understanding of how the interaction of service loads and environment influences the lifecycle of emerging structures and materials

  14. Damage Mechanisms and Mechanical Properties of High-Strength Multiphase Steels

    Directory of Open Access Journals (Sweden)

    Sebastian Heibel

    2018-05-01

    Full Text Available The usage of high-strength steels for structural components and reinforcement parts is inevitable for modern car-body manufacture in reaching lightweight design as well as increasing passive safety. Depending on their microstructure these steels show differing damage mechanisms and various mechanical properties which cannot be classified comprehensively via classical uniaxial tensile testing. In this research, damage initiation, evolution and final material failure are characterized for commercially produced complex-phase (CP and dual-phase (DP steels in a strength range between 600 and 1000 MPa. Based on these investigations CP steels with their homogeneous microstructure are characterized as damage tolerant and hence less edge-crack sensitive than DP steels. As final fracture occurs after a combination of ductile damage evolution and local shear band localization in ferrite grains at a characteristic thickness strain, this strain measure is introduced as a new parameter for local formability. In terms of global formability DP steels display advantages because of their microstructural composition of soft ferrite matrix including hard martensite particles. Combining true uniform elongation as a measure for global formability with the true thickness strain at fracture for local formability the mechanical material response can be assessed on basis of uniaxial tensile testing incorporating all microstructural characteristics on a macroscopic scale. Based on these findings a new classification scheme for the recently developed high-strength multiphase steels with significantly better formability resulting of complex underlying microstructures is introduced. The scheme overcomes the steel designations using microstructural concepts, which provide no information about design and production properties.

  15. Manufacturing technology of high-quality pressure castings

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2011-10-01

    Full Text Available The paper presents manufacturing technology of pressure castings made of Al-Si alloy without porosity or with low microporosity of castings. It has been shown that the greatest impact on the porosity of the castings and the concentration of hydrogen has had the charge to the melting furnace. Liquidation or occurrence of a small microporosity of castings provides refining with solid refiners, nitrogen and modification of liquid alloy after various operations of preparing process. The liquid alloy stored in holding furnace should be refined once every 2 h with nitrogen. Authors developed a computer program of Al-Si alloys inspection with using of TDA method. The developed technology was verified under production conditions.

  16. Highly Manufacturable Deep (Sub-Millimeter) Etching Enabled High Aspect Ratio Complex Geometry Lego-Like Silicon Electronics

    KAUST Repository

    Ghoneim, Mohamed T.; Hussain, Muhammad Mustafa

    2017-01-01

    A highly manufacturable deep reactive ion etching based process involving a hybrid soft/hard mask process technology shows high aspect ratio complex geometry Lego-like silicon electronics formation enabling free-form (physically flexible

  17. Development of martensitic steels for high neutron damage applications

    International Nuclear Information System (INIS)

    Gelles, D.S.

    1998-01-01

    Martensitic stainless steels have been developed for both in-core applications in advanced liquid metal fast breeder reactors (LMFBR) and for first wall and structural materials applications for commercial fusion reactors. It can now be shown that these steels can be expected to maintain properties to levels as high as 175 or 200 dpa, respectively. The 12Cr-1Mo-0.5W-0.2C alloy HT-9 has been extensively tested for LMFBR applications and shown to resist radiation damage, providing a creep and swelling resistant alternative to austenitic steels. Degradation of fracture toughness and Charpy impact properties have been observed, but properties are sufficient to provide reliable service. In comparison, alloys with lower chromium contents are found to decarburize in contact with liquid sodium and are therefore not recommended. Tungsten stabilized martensitic stainless steels have appropriate properties for fusion applications. Radioactivity levels are being less than 500 years after service, radiation damage resistance is excellent, including impact properties, and swelling is modest. This report describes the history of the development effort. (author)

  18. Development of martensitic steels for high neutron damage applications

    Science.gov (United States)

    Gelles, D. S.

    1996-12-01

    Martensitic stainless steels have been developed for both in-core applications in advanced liquid metal fast breeder reactors (LMFBR) and for first wall and structural materials applications for commercial fusion reactors. It can now be shown that these steels can be expected to maintain properties to levels as high as 175 or 200 dpa, respectively. The 12Cr1Mo0.5W0.2C alloy HT-9 has been extensively tested for LMFBR applications and shown to resist radiation damage, providing a creep and swelling resistant alternative to austenitic steels. Degradation of fracture toughness and Charpy impact properties have been observed, but properties are sufficient to provide reliable service. In comparison, alloys with lower chromium contents are found to decarburize in contact with liquid sodium and are therefore not recommended. Tungsten stabilized martensitic stainless steels have appropriate properties for fusion applications. Radioactivity levels are benign less than 500 years after service, radiation damage resistance is excellent, including impact properties, and swelling is modest. This report describes the history of the development effort.

  19. Damage of plasmid DNA by high energy ions

    International Nuclear Information System (INIS)

    Michaelidesova, A.; Pachnerova Brabcova, K.; Davidkova, M.

    2018-01-01

    The aim of the study was to determine the degree of direct DNA damage by high-energy ions, which are one of the components of cosmic rays, and therefore the knowledge of the biological effects of these ions is key to long-term space missions with human crew. The pBR322 plasmid containing 4361 base pairs was used in this study. The aqueous solution of plasmid pBR322 was transferred on ice to Japan to the Heavy Ion Medical Accelerator in Chiba, the Research Center for Charged Particle Therapy. Just before the experiment, the droplets of solution of known concentration were applied to the slides and the water was allowed to evaporate to produce dry DNA samples. Half of the slides were irradiated with 290 MeV/u of carbon ions and a dose rate of 20 Gy/min. The other half of the slides were irradiated with helium nuclei of 150 MeV/hr and a dose rate of 12.6 Gy/min. Both sets of slides were irradiated with doses of 0-1,400 Gy with a 200 Gy step. After irradiation, the samples were re-dissolved in distilled water, frozen and transported on ice to the Czech Republic for processing. Samples were analyzed by agarose gel electrophoresis. The plasmid was evaluated separately to determine the degree of radiation induced lesions and further to incubation with enzymes recognizing basal damage. (authors)

  20. High-kinetic inductance additive manufactured superconducting microwave cavity

    Science.gov (United States)

    Holland, Eric T.; Rosen, Yaniv J.; Materise, Nicholas; Woollett, Nathan; Voisin, Thomas; Wang, Y. Morris; Torres, Sharon G.; Mireles, Jorge; Carosi, Gianpaolo; DuBois, Jonathan L.

    2017-11-01

    Investigations into the microwave surface impedance of superconducting resonators have led to the development of single photon counters that rely on kinetic inductance for their operation, while concurrent progress in additive manufacturing, "3D printing," opens up a previously inaccessible design space for waveguide resonators. In this manuscript, we present results from the synthesis of these two technologies in a titanium, aluminum, vanadium (Ti-6Al-4V) superconducting radio frequency resonator which exploits a design unattainable through conventional fabrication means. We find that Ti-6Al-4V has two distinct superconducting transition temperatures observable in heat capacity measurements. The higher transition temperature is in agreement with DC resistance measurements, while the lower transition temperature, not previously known in the literature, is consistent with the observed temperature dependence of the superconducting microwave surface impedance. From the surface reactance, we extract a London penetration depth of 8 ± 3 μm—roughly an order of magnitude larger than other titanium alloys and several orders of magnitude larger than other conventional elemental superconductors.

  1. Development of a virtual metrology for high-mix TFT-LCD manufacturing processes

    International Nuclear Information System (INIS)

    Chen Shan; Pan Tianhong; Jang Shishang

    2010-01-01

    Nowadays, TFT-LCD manufacturing has become a very complex process, in which many different products being manufactured with many different tools. The ability to predict the quality of product in such a high-mix system is critical to developing and maintaining a high yield. In this paper, a statistical method is proposed for building a virtual metrology model from a number of products using a high-mix manufacturing process. Stepwise regression is used to select 'key variables' that really affect the quality of the products. Multivariate analysis of covariance is also proposed for simultaneously applying the selected variables and product effect. This framework provides a systematic method of building a processing quality prediction system for a high-mix manufacturing process. The experimental results show that the proposed quality prognostic system can not only estimate the critical dimension accurately but also detect potentially faulty glasses.

  2. Prediction of high frequency core loss for electrical steel using the data provided by manufacturer

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Rakesh [National Institute of Technology Meghalaya, Shillong (India); Dalal, Ankit; Kumar, Praveen [Indian Institute of Technology Guwahati, Assam (India)

    2016-07-15

    This paper describes a technique to determine the core loss data, at high frequencies, using the loss data provided by the lamination manufacturer. Steinmetz equation is used in this proposed method to determine core loss at high frequency. This Steinmetz equation consists of static hysteresis and eddy current loss. The presented technique considers the coefficients of Steinmetz equation as variable with frequency and peak magnetic flux density. The high frequency core loss data, predicted using this model is compared with the catalogue data given by manufacturer and very good accuracy has been obtained for a wide range of frequency. - Highlights: • A curve fitting algorithm is proposed to predict core loss at high frequency. • The loss data given by the steel manufacturers are used in curve fitting algorithm. • The algorithm is tested on nine different material’s data set given by the manufacturer.

  3. Prediction of high frequency core loss for electrical steel using the data provided by manufacturer

    International Nuclear Information System (INIS)

    Roy, Rakesh; Dalal, Ankit; Kumar, Praveen

    2016-01-01

    This paper describes a technique to determine the core loss data, at high frequencies, using the loss data provided by the lamination manufacturer. Steinmetz equation is used in this proposed method to determine core loss at high frequency. This Steinmetz equation consists of static hysteresis and eddy current loss. The presented technique considers the coefficients of Steinmetz equation as variable with frequency and peak magnetic flux density. The high frequency core loss data, predicted using this model is compared with the catalogue data given by manufacturer and very good accuracy has been obtained for a wide range of frequency. - Highlights: • A curve fitting algorithm is proposed to predict core loss at high frequency. • The loss data given by the steel manufacturers are used in curve fitting algorithm. • The algorithm is tested on nine different material’s data set given by the manufacturer.

  4. Scanning the horizon for high value-add manufacturing science: Accelerating manufacturing readiness for the next generation of disruptive, high-value curative cell therapeutics.

    Science.gov (United States)

    Hourd, Paul; Williams, David J

    2018-05-01

    Since the regenerative medicine sector entered the second phase of its development (RegenMed 2.0) more than a decade ago, there is increasing recognition that current technology innovation trajectories will drive the next translational phase toward the production of disruptive, high-value curative cell and gene-based regenerative medicines. To identify the manufacturing science problems that must be addressed to permit translation of these next generation therapeutics. In this short report, a long lens look within the pluripotent stem cell therapeutic space, both embryonic and induced, is used to gain early insights on where critical technology and manufacturing challenges may emerge. This report offers a future perspective on the development and innovation that will be needed within manufacturing science to add value in the production and commercialization of the next generation of advanced cell therapies and precision medicines. Copyright © 2018 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  5. A novel theory of radiation damage at high doses

    International Nuclear Information System (INIS)

    Seeger, A.; Stuttgart Univ.

    1989-01-01

    Deviations of radiation damage (in the case of metals usually monitored by the residual electrical resistivity) from proportionality with the irradiation dose have so far been analysed almost exclusively in terms of extensions of models originally developed for small doses. The present theory considers the opposite limit i.e. the quasi-saturated state. It is argued that at high doses the Lueck-Sizmann effect may result in a self-organization of clusters of vacancies and self-interstitials, forming a heterogeneous froth. Possible structures of this froth and its effect on the electrical resistivity of metals are discussed. The model is shown to account for the dependence of the ''saturation resistivity'' on the nature of the irradiation as well as for several other hitherto poorly explained observations. Among them are the electrical-resistivity variation induced by high-dose irradiation with heavy ions, the amorphization of certain alloys by high-dose electron irradiation, and the occurrence of ordered arrays of stacking-fault tetrahedra after in-situ irradiations in high-voltage electron microscopes. (author)

  6. EUV mask defect inspection and defect review strategies for EUV pilot line and high volume manufacturing

    Science.gov (United States)

    Chan, Y. David; Rastegar, Abbas; Yun, Henry; Putna, E. Steve; Wurm, Stefan

    2010-04-01

    Reducing mask blank and patterned mask defects is the number one challenge for extreme ultraviolet lithography. If the industry succeeds in reducing mask blank defects at the required rate of 10X every year for the next 2-3 years to meet high volume manufacturing defect requirements, new inspection and review tool capabilities will soon be needed to support this goal. This paper outlines the defect inspection and review tool technical requirements and suggests development plans to achieve pilot line readiness in 2011/12 and high volume manufacturing readiness in 2013. The technical specifications, tooling scenarios, and development plans were produced by a SEMATECH-led technical working group with broad industry participation from material suppliers, tool suppliers, mask houses, integrated device manufacturers, and consortia. The paper summarizes this technical working group's assessment of existing blank and mask inspection/review infrastructure capabilities to support pilot line introduction and outlines infrastructure development requirements and tooling strategies to support high volume manufacturing.

  7. Nanoimprint system development and status for high volume semiconductor manufacturing

    Science.gov (United States)

    Hiura, Hiromi; Takabayashi, Yukio; Takashima, Tsuneo; Emoto, Keiji; Choi, Jin; Schumaker, Phil

    2016-10-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography* (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. There are many criteria that determine whether a particular technology is ready for wafer manufacturing. For imprint lithography, recent attention has been given to the areas of overlay, throughput, defectivity, and mask replication. This paper reviews progress in these critical areas. Recent demonstrations have proven that mix and match overlay of less than 5nm can achieved. Further reductions require a higher order correction system. Modeling and experimental data are presented which provide a path towards reducing the overlay errors to less than 3nm. Throughput is mainly impacted by the fill time of the relief images on the mask. Improvement in resist materials provides a solution that allows 15 wafers per hour per station, or a tool throughput of 60 wafers per hour. Defectivity and mask life play a significant role relative to meeting the cost of ownership (CoO) requirements in the production of semiconductor devices. Hard particles on a wafer or mask create the possibility of inducing a permanent defect on the mask that can impact device yield and mask life. By using material methods to reduce particle shedding and by introducing an air curtain system, the lifetime of both the master mask and the replica mask can be extended. In this work, we report results that demonstrate a path towards achieving mask lifetimes of better than 1000 wafers. Finally, on the mask side, a new replication tool, the FPA-1100NR2 is

  8. Qualification of high-density fuel manufacturing for research reactors at CNEA

    Energy Technology Data Exchange (ETDEWEB)

    Adelfang, P.; Alvarez, L.; Boero, N.; Calabrese, R.; De La Fuente, M.; Echenique, P.; Markiewicz, M.; Pasqualini, E.; Ruggirello, G.; Taboada, H. [CNEA, Buenos Aires (Argentina)

    2001-07-01

    CNEA, the National Atomic Energy Commission of Argentina, is at the present a qualified supplier of uranium oxide fuel for research reactors. A new objective in this field is to develop and qualify the manufacturing of LEU high-density fuel for this type of reactors. According with the international trend Silicide fuel and U-xMo fuel are included in our program as the most suitable options. The facilities to complete the qualification of high-density MTR fuels, like the manufacturing plant installations, the reactor, the pool side fuel examination station and the hot cells are fully operational and equipped to perform all the activities required within the program. The programs for both type of fuels include similar activities: development and set up of the fuel material manufacturing technology, set up of fuel plate manufacturing, fabrication and irradiation of miniplates, fabrication and irradiation of full scale fuel elements, post-irradiation examination and feedback for manufacturing improvements. For silicide fuels most of these steps have already been completed. For U-xMo fuel the activities also include the development of alternative ways to obtain U-xMo powder, feasibility studies for large-scale manufacturing and the economical assessment. Set up of U-xMo fuel plate manufacturing is also well advanced and the fabrication of the first full scale prototype is foreseen during this year. (author)

  9. Investigating coseismic fracture damage using a new high speed triaxial apparatus

    Science.gov (United States)

    Mitchell, T. M.; Aben, F. M.; Pricci, R.; Brantut, N.; Rockwell, T. K.; Boon, S.

    2017-12-01

    The occurence of pulverized rocks, a type of intensely damaged fault rock which has undergone minimal shear strain, has been linked to damage induced by transient high strain-rate stress perturbations during earthquake rupture. Damage induced by such transient stresses, whether compressional or tensional, likely constitute heterogeneous modulations of the remote stresses that will impart significant changes on the strength, elastic and fluid flow properties of a fault zone immediately after rupture propagation, at the early stage of fault slip. While the physical mechanisms for pulverized rock generation are still not yet fully understood, it is likely that they are in some way related to a combination of the dynamic compressive and tensional stresses imparted on the rock surrounding a fault at the tip of a propagating earthquake rupture. Typical triaxial rock deformation apparatuses are limited by their loading systems to strain rates on the order of 10-4 s-1, which in terms of the seismic cycle, is only applicable to processes operating within the inter-seismic period. In order to achieve strain rates in excess of 100 s-1 under confined conditions with pore fluids (currently unachievable with conventional deformation apparatus such as split bar Hopkinson), we have designed, manufactured and constructed a new high strain rate triaxial rock deformation apparatus, with a unique innovative hydraulic loading system that allows samples to be deformed in compression and tension at strain rates from 10-7 up to 200 s-1 . We present preliminary data demonstrating the unique capability of this apparatus to produce co-seismic experimental conditions not previously acheived.

  10. Electron-beam damaged high-temperature superconductor Josephson junctions

    International Nuclear Information System (INIS)

    Pauza, A.J.; Booij, W.E.; Herrmann, K.; Moore, D.F.; Blamire, M.G.; Rudman, D.A.; Vale, L.R.

    1997-01-01

    Results are presented on the fabrication and characterization of high critical temperature Josephson junctions in thin films of YBa 2 Cu 3 O 7-δ produced by the process of focused electron-beam irradiation using 350 keV electrons. The junctions so produced have uniform spatial current densities, can be described in terms of the resistive shunted junction model, and their current densities can be tailored for a given operating temperature. The physical properties of the damaged barrier can be described as a superconducting material of either reduced or zero critical temperature (T c ), which has a length of ∼15nm. The T c reduction is caused primarily by oxygen Frenkel defects in the Cu - O planes. The large beam currents used in the fabrication of the junctions mean that the extent of the barrier is limited by the incident electron-beam diameter, rather than by scattering within the film. The properties of the barrier can be calculated using a superconductor/normal/superconductor (SNS) junction model with no boundary resistance. From the SNS model, we can predict the scaling of the critical current resistance (I c R n ) product and gain insight into the factors controlling the junction properties, T c , and reproducibility. From the measured I c R n scaling data, we can predict the I c R n product of a junction at a given operating temperature with a given current density. I c R n products of ∼2mV can be achieved at 4.2 K. The reproducibility of several junctions in a number of samples can be characterized by the ratio of the maximum-to-minimum critical currents on the same substrate of less than 1.4. Stability over several months has been demonstrated at room and refrigerator temperatures (297 and 281 K) for junctions that have been initially over damaged and then annealed at temperatures ∼380K. (Abstract Truncated)

  11. Evaluation of Additive Manufacturing for High Volume Composite Part Molds

    Energy Technology Data Exchange (ETDEWEB)

    Duty, Chad E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kunc, Vlastimil [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lokitz, Bradley S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Springfield, Robert M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-05-01

    ORNL worked with TruDesign, LLC to develop viable coating solutions to enable the use of large scale 3D printing for both low-temperature and high-temperature composite molds. This project resulted in two commercial products and successfully demonstrated the use of printed molds for autoclave processing for the first time.

  12. Relationship between permeability and damage in concretes at high temperature

    International Nuclear Information System (INIS)

    Dal Pont, St.

    2004-09-01

    Due to its technical and economical advantages, concrete is nowadays the most used building material in civil engineering. Even if its use is known since nearly two centuries, its behavior has not been yet completely explained due to the complexity of its porous microstructure. This fact is quite evident under particular conditions such as, by instance, during an elevation of temperature. This condition can mainly occur in two cases: due to a casualty (e.g. a fire) or in normal use conditions (e.g. storage of nuclear rejects). This work aims at contributing to the study of the phenomena that can be observed in concrete exposed to high temperatures and, in particular, focuses on the study of the evolution of intrinsic permeability. The characterisation of permeability (which is hardly measurable in hot conditions) is necessary for describing and modelling transport phenomena which occur in porous media. An experimental study has been made in collaboration with the CEA. A real-scale hollow cylinder has been instrumented with gauges for studying the evolution of temperature and gas pressure fields inside concrete. Later, the cylinder has been then numerically modelled by means of a thermo-hydro-chemical (THC) and a thermo-hydro-chemo-mechanical (THCM) model. The THC model, implemented by means of the finite volume method, has allowed a first, qualitative study of the behaviour of concrete submitted to high temperature. This model, which, for sake of simplicity, has neglected all mechanical effects, has allowed the description of the main phenomena occurring inside concrete: mass transport, phase changes, microstructure evolution. Later, the modelling has been completed by means of the THCM model using the Hitecosp code, implemented by means of the finite element method at the university of Padua. This code allows a very complete description of the phenomena occurring inside concrete and takes into consideration the mechanical behavior of concrete by means of an

  13. High temperature structural ceramic materials manufactured by the CNTD process

    International Nuclear Information System (INIS)

    Stiglich, J.J. Jr.; Bhat, D.G.; Holzl, R.A.

    1980-01-01

    Controlled Nucleation Thermochemical Deposition (CNTD) has emerged from classical chemical deposition (CVD) technology. This paper describes the techniques of thermochemical grain refinement. The effects of such refinement on mechanical properties of materials at room temperature and at elevated temperatures are outlined. Emphasis is given to high temperature structural ceramic materials such as SiC, Si 3 N 4 , AlN, and TiB 2 and ZrB 2 . An example of grain refinement accompanied by improvements in mechanical properties is SiC. Grain sizes of 500 to 1000 A have been observed in CNTD SiC with room temperature MOR of 1380 to 2070 MPa (4 pt bending) and MOR of 3450 to 4140 MPa (4 pt bending) at 1350 0 C. Various applications of these materials to the solution of high temperature structural problems are described. (author)

  14. High energy laser optics manufacturing: a preliminary study

    International Nuclear Information System (INIS)

    Baird, E.D.

    1980-07-01

    This report presents concepts and methods, major conclusions, and major recommendations concerning the fabrication of high energy laser optics (HELO) that are to be machined by the Large Optics Diamond Turning Machine (LODTM) at the Lawrence Livermore National Laboratory (LLNL). Detailed discussions of concepts and methods proposed for metrological operations, polishing of reflective surfaces, mounting of optical components, construction of mirror substrates, and applications of coatings are included

  15. Articles for high temperature service and methods for their manufacture

    Science.gov (United States)

    Sarrafi-Nour, Reza; Meschter, Peter Joel; Johnson, Curtis Alan; Luthra, Krishan Lal; Rosenzweig, Larry Steven

    2016-06-14

    An article for use in aggressive environments is presented. In one embodiment, the article comprises a substrate and a self-sealing and substantially hermetic sealing layer comprising an alkaline-earth aluminosilicate disposed over the bondcoat. The substrate may be any high-temperature material, including, for instance, silicon-bearing ceramics and ceramic matrix composites. A method for making such articles is also presented. The method comprises providing a substrate; disposing a self-sealing alkaline-earth aluminosilicate layer over the substrate; and heating the sealing layer to a sealing temperature at which at least a portion of the sealing layer will flow.

  16. Internal Fiber Structure of a High-Performing, Additively Manufactured Injection Molding Insert

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Baier, Sina; Trinderup, Camilla H.

    A standard mold is equipped with additively manufactured inserts in a rectangular shape produced with vat photo polymerization. While the lifetime compared to conventional materials such as brass, steel, and aluminum is reduced, the prototyping and design phase can be shortened significantly...... by using flexible and cost-effective additive manufacturing technologies. Higher production volumes still exceed the capability of additively manufactured inserts, which are overruled by the stronger performance of less-flexible but mechanically advanced materials. In this contribution, the internal...... structure of a high-performing, fiber-reinforced injection molding insert has been analyzed. The insert reached a statistically proven and reproducible lifetime of 4,500 shots, which significantly outperforms any other previously published additively manufactured inserts. Computer tomography, tensile tests...

  17. Effect of low dose pre-irradiation on DNA damage and genetic material damage caused by high dosage of cyclophosphamide

    International Nuclear Information System (INIS)

    Yu Hongsheng; Zhu Jingjuan; Shang Qingjun; Wang Zhuomin; Cui Fuxian

    2007-01-01

    Objective: To study the effect of low dose γ-rays pre-irradiation on the induction of DNA damage and genetic material damage in peripheral lymphocytes by high dosage of cyclophosphamide (CTX). Methods: Male Kunming strain mice were randomly divided into five groups: control group, sham-irradiated group, low dose irradiated group(LDR group), cyclophosphamide chemotherapy group(CTX group) and low dose irradiation combined with chemotherapy group(LDR + CTX group). After being feeded for one week, all the mice were implanted subcutaneously with S180 cells in the left groin (control group excluded). On days 8 and 11, groups of LDR and LDR + CTX were administered with 75 mGy of whole-body irradiation, 30 h later groups CTX and LDR + CTX were injected intraperitoneally 3.0 mg cyclophosphamide. All the mice were sacrificed on day 13. DNA damage of the peripheral lymphocytes was analyzed using single cell gel electrophoresis (SCGE). Genetic material damage was analyzed using micronucleus frequency(MNF) of polychromatoerythrocytes(PCE) in bone marrow. Results: (1) Compared with control group and sham-irradiated group, the DNA damage of peripheral lymphocytes in CTX group were increased significantly (P 0.05). Conclusions: (1) High- dosage of CTX chemotherapy can cause DNA damage in peripheral lymphocytes. 75 mGy y-irradiation before chemotherapy may have certain protective effect on DNA damage. (2) CTX has potent mutagenic effect, giving remarkable rise to MNF of PCE. 75 mGy γ-ray pre-irradiation has not obvious protection against genetic toxicity of high-dose CTX chemotherapy. (authors)

  18. Trial manufacture of liquid nitrogen cooling High Temperature Superconductivity Motor

    International Nuclear Information System (INIS)

    Sugimoto, H; Nishikawa, T; Tsuda, T; Hondou, Y; Akita, Y; Takeda, T; Okazaki, T; Ohashi, S; Yoshida, Y

    2006-01-01

    We present a new high temperature superconductivity (HTS) synchronous motor using the liquid nitrogen as the refrigerant in this paper. This motor is designed to be used as the propulsion motor in ship. Because we use the liquid nitrogen as the refrigerant, it is possible to simplify the cooling equipments in the motor. And in our design, we apply the axial flux type of motor to simplify the cryostat of the HTS wires used to make the field coils. Here, the fields using the bismuth HTS wire for the HTS coils are fixed. Moreover, the cores used in the fields are separated from cryostat, and the armature applies the core-less structure. According to various the electromagnetic field analysis results, the new motor was designed and produced. The diameter of the motor is 650mm, and the width of the motor is 360mm. The motor's rated output is 8.8kW at 100rpm, while the overload output is 44kW, and the maximum efficiency is 97.7%. Also, in order to further miniaturize the motor, other magnetic field analysis have been done when the high-current-density type HTS wire was used and the permendur was used instead of magnetic steel plates. In this case, the motor's rated output is 12kW, and the overload output is 60kW

  19. Radiation damage in diatomic materials at high doses

    International Nuclear Information System (INIS)

    Hobbs, L.W.; Hughes, A.E.

    1975-10-01

    Radiation effects in diatomic materials can differ structurally from those in metals because of the need to take into account different displacement rates on the two sublattices and the inevitable stoichiometric implications; in most diatomic insulators the anion species has the greater displacement cross section. Anion point defect stabilisation in heavily-irradiated (0.1 to 10 dpa) diatomic insulators has been studied using radiolysis of alkali and alkaline earth halides. A temperatures > 0.3 Tsub(m), all anion defects are mobile and can aggregate. Aggregation of anion interstitials results in creation of perfect dislocation loops without the need for primary cation displacements; simultaneous formation of substitutional anion molecular centres provides the necessary cation interstitials. Aggregation of anion vacancies leads to formation of metallic inclusions of the cation species, in some cases in an ordered array, which is the analogue, on a single sublattice, to the void lattice in metals. Availability of sinks for both anion interstitials and anion vacancies yields defect growth kinetics similar to those observed during formation of voids in irradiated metals, and a very high level of damage (approximately 10%) can be sustained in the lattice. The width of the temperature region concerned is much narrower, however, due to the possibility of recombination of aggregated or re-emitted anion vacancies with mobile or dispersed anion molecular defects; the latter can also aggregate to form fluid anion molecular inclusions and so complete the decomposition of the solid into separate phases of its constituent elements. (author)

  20. High-volume manufacturing device overlay process control

    Science.gov (United States)

    Lee, Honggoo; Han, Sangjun; Woo, Jaeson; Lee, DongYoung; Song, ChangRock; Heo, Hoyoung; Brinster, Irina; Choi, DongSub; Robinson, John C.

    2017-03-01

    Overlay control based on DI metrology of optical targets has been the primary basis for run-to-run process control for many years. In previous work we described a scenario where optical overlay metrology is performed on metrology targets on a high frequency basis including every lot (or most lots) at DI. SEM based FI metrology is performed ondevice in-die as-etched on an infrequent basis. Hybrid control schemes of this type have been in use for many process nodes. What is new is the relative size of the NZO as compared to the overlay spec, and the need to find more comprehensive solutions to characterize and control the size and variability of NZO at the 1x nm node: sampling, modeling, temporal frequency and control aspects, as well as trade-offs between SEM throughput and accuracy.

  1. Advances and highlights of the CNEA qualification program as high density fuel manufacturer for research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Adelfang, P.; Alvarez, L.; Boero, N.; Calabrese, R.; Echenique, P.; Markiewicz, M.; Pasqualini, E.; Ruggirello, G.; Taboada, H. [Unidad de Actividad Combustibles Nucleares Comision Nacional de Energia Atomica (CNE4), Avda. del Libertador, 8250 C1429BNO Buenos Aires (Argentina)

    2002-07-01

    One of the main objectives of CNEA regarding the fuel for research reactors is the development and qualification of the manufacturing of LEU high-density fuels. The qualification programs for both types of fuels, Silicide fuel and U- x Mo fuel, are similar. They include the following activities: development and set up of the fissile compound manufacturing technology, set up of fuel plate manufacturing, fabrication and irradiation of mini plates and plates, design and fabrication of fuel assembly prototypes for irradiation, post-irradiation examination and feedback for manufacturing improvements. This paper describes the different activities performed within each program during the last year and the main advances and achievements of the programs within this period. The main achievements may be summarized in the following activities: Continuation of the irradiation of the first silicide fuel element in the R A3. Completion of the manufacturing of the second silicide fuel element, licensing and beginning of its irradiation in the R A3. Development of the HMD Process to manufacture U-Mo powder (pUMA project). Set up of fuel plates manufacturing at industrial level using U-Mo powder. Preliminary studies and the design for the irradiation of mini plates, plates and full scale fuel elements with U-Mo and 7 g U/cm{sup 3}. PIE destructive studies for the P-04 silicide fuel prototype (accurate burnup determination through chemical analysis, metallography and SEM of samples from the irradiated fuel plates). Improvement and development of new characterization techniques for high density fuel plates quality control including US testing and densitometric analysis of X-ray examinations. The results obtained in this period are encouraging and also allow to foresee a wider participation of CNEA in the international effort to qualify U-Mo as a new material for the manufacturing of research reactor fuels. (author)

  2. Advances and highlights of the CNEA qualification program as high density fuel manufacturer for research reactors

    International Nuclear Information System (INIS)

    Adelfang, P.; Alvarez, L.; Boero, N.; Calabrese, R.; Echenique, P.; Markiewicz, M.; Pasqualini, E.; Ruggirello, G.; Taboada, H.

    2002-01-01

    One of the main objectives of CNEA regarding the fuel for research reactors is the development and qualification of the manufacturing of LEU high-density fuels. The qualification programs for both types of fuels, Silicide fuel and U- x Mo fuel, are similar. They include the following activities: development and set up of the fissile compound manufacturing technology, set up of fuel plate manufacturing, fabrication and irradiation of mini plates and plates, design and fabrication of fuel assembly prototypes for irradiation, post-irradiation examination and feedback for manufacturing improvements. This paper describes the different activities performed within each program during the last year and the main advances and achievements of the programs within this period. The main achievements may be summarized in the following activities: Continuation of the irradiation of the first silicide fuel element in the R A3. Completion of the manufacturing of the second silicide fuel element, licensing and beginning of its irradiation in the R A3. Development of the HMD Process to manufacture U-Mo powder (pUMA project). Set up of fuel plates manufacturing at industrial level using U-Mo powder. Preliminary studies and the design for the irradiation of mini plates, plates and full scale fuel elements with U-Mo and 7 g U/cm 3 . PIE destructive studies for the P-04 silicide fuel prototype (accurate burnup determination through chemical analysis, metallography and SEM of samples from the irradiated fuel plates). Improvement and development of new characterization techniques for high density fuel plates quality control including US testing and densitometric analysis of X-ray examinations. The results obtained in this period are encouraging and also allow to foresee a wider participation of CNEA in the international effort to qualify U-Mo as a new material for the manufacturing of research reactor fuels. (author)

  3. Prediction of high frequency core loss for electrical steel using the data provided by manufacturer

    Science.gov (United States)

    Roy, Rakesh; Dalal, Ankit; Kumar, Praveen

    2016-07-01

    This paper describes a technique to determine the core loss data, at high frequencies, using the loss data provided by the lamination manufacturer. Steinmetz equation is used in this proposed method to determine core loss at high frequency. This Steinmetz equation consists of static hysteresis and eddy current loss. The presented technique considers the coefficients of Steinmetz equation as variable with frequency and peak magnetic flux density. The high frequency core loss data, predicted using this model is compared with the catalogue data given by manufacturer and very good accuracy has been obtained for a wide range of frequency.

  4. An analysis of the development of high temperature cavitation damage

    International Nuclear Information System (INIS)

    Tinivella, R.

    1986-07-01

    The objective of the paper is the investigation of creep cavitation damage in copper. Radii distribution curves obtained from small angle neutron scattering experiments conducted on crept specimens were analyzed and compared with calculated curves. The latter were derived from cavity nucleation- and growth models. From the comparison the appropriateness of particular models can be infered. Valuable information is obtained about the nucleation behaviour. In crept and fatigued specimens, already after very short loading times, cavities appear with remarkable different radii, an observation which is contradictory to the concept of a critical radius. The analysis of the nucleation behavior emphasizes the influence of the stress dependence of the nucleation rate upon the stress dependence of damage and hence upon the stress dependence of the lifetime. In most of damage theories the latter is attributed to the stress dependency of cavity growth. A strong argument is derived in this paper in favour of the idea that both the mechanisms - growth and nucleation - contribute to the stress dependence of the lifetime. The damage development in Cu (as well as in alpha-Fe, AISI 304 and AISI 347) is compared with the prediction of the phenomenological A-model which assumes that the damage rate is proportional to the damage itself. The experiments show, that the damage increases in time slower (Cu, alpha-Fe, AISI 304) or faster (AISI 347) than predicted by the model. In copper the damage rate turns out to be constant independent of time. Accordingly the A-model is modified and the respective consequences are briefly discussed. (orig./GSCH) [de

  5. Ductile failure analysis of high strength steel in hot forming based on micromechanical damage model

    OpenAIRE

    Ying Liang; Liu Wenquan; Wang Dantong; Hu Ping

    2016-01-01

    The damage evolution of high strength steel at elevated temperature is investigated by using the Gurson-Tvergaard-Needleman (GTN) model. A hybrid method integrated thermal tensile test and numerical technique is employed to identify the damage parameters. The analysis results show that the damage parameters are different at different temperature as the variation of tested material microstructure. Furthermore, the calibrated damage parameters are implemented to simulate a bugling forming at el...

  6. Process for the manufacture of a stabilized filament superconductor with a high proportion of stabilising material

    International Nuclear Information System (INIS)

    Both, R.; Hillmann, H.; Breuer, W.

    1987-01-01

    In order to manufacture superconductors with a high proportion of stabilising material, a compound body is first formed and is formed by extrusion and drawing to reduce its crossection. This compound body is then introduced into a sheath tube to increase the proportion of stabilising material and is formed to its final dimensions by further drawing processes. Tearing of the superconducting filaments is prevented by sufficient stabilising material (e.g. copper here) being introduced in the central area of the compound body. The filament superconductors can be manufactured at a reasonable price with a high proportion of stabilising material. (orig.) [de

  7. Radiation damage in silicon exposed to high-energy protons

    International Nuclear Information System (INIS)

    Davies, Gordon; Hayama, Shusaku; Murin, Leonid; Krause-Rehberg, Reinhard; Bondarenko, Vladimir; Sengupta, Asmita; Davia, Cinzia; Karpenko, Anna

    2006-01-01

    Photoluminescence, infrared absorption, positron annihilation, and deep-level transient spectroscopy (DLTS) have been used to investigate the radiation damage produced by 24 GeV/c protons in crystalline silicon. The irradiation doses and the concentrations of carbon and oxygen in the samples have been chosen to monitor the mobility of the damage products. Single vacancies (and self-interstitials) are introduced at the rate of ∼1 cm -1 , and divacancies at 0.5 cm -1 . Stable di-interstitials are formed when two self-interstitials are displaced in one damage event, and they are mobile at room temperature. In the initial stages of annealing the evolution of the point defects can be understood mainly in terms of trapping at the impurities. However, the positron signal shows that about two orders of magnitude more vacancies are produced by the protons than are detected in the point defects. Damage clusters exist, and are largely removed by annealing at 700 to 800 K, when there is an associated loss of broad band emission between 850 and 1000 meV. The well-known W center is generated by restructuring within clusters, with a range of activation energies of about 1.3 to 1.6 eV, reflecting the disordered nature of the clusters. Comparison of the formation of the X centers in oxygenated and oxygen-lean samples suggests that the J defect may be interstitial related rather than vacancy related. To a large extent, the damage and annealing behavior may be factorized into point defects (monitored by sharp-line optical spectra and DLTS) and cluster defects (monitored by positron annihilation and broadband luminescence). Taking this view to the limit, the generation rates for the point defects are as predicted by simply taking the damage generated by the Coulomb interaction of the protons and Si nuclei

  8. Precision manufacturing

    CERN Document Server

    Dornfeld, David

    2008-01-01

    Today there is a high demand for high-precision products. The manufacturing processes are now highly sophisticated and derive from a specialized genre called precision engineering. Precision Manufacturing provides an introduction to precision engineering and manufacturing with an emphasis on the design and performance of precision machines and machine tools, metrology, tooling elements, machine structures, sources of error, precision machining processes and precision process planning. As well as discussing the critical role precision machine design for manufacturing has had in technological developments over the last few hundred years. In addition, the influence of sustainable manufacturing requirements in precision processes is introduced. Drawing upon years of practical experience and using numerous examples and illustrative applications, David Dornfeld and Dae-Eun Lee cover precision manufacturing as it applies to: The importance of measurement and metrology in the context of Precision Manufacturing. Th...

  9. Manufacturing a Long-Period Grating with Periodic Thermal Diffusion Technology on High-NA Fiber and Its Application as a High-Temperature Sensor.

    Science.gov (United States)

    Shen, Xiang; Dai, Bin; Xing, Yingbin; Yang, Luyun; Li, Haiqing; Li, Jinyan; Peng, Jingang

    2018-05-08

    We demonstrated a kind of long-period fiber grating (LPFG), which is manufactured with a thermal diffusion treatment. The LPFG was inscribed on an ultrahigh-numerical-aperture (UHNA) fiber, highly doped with Ge and P, which was able to easily diffuse at high temperatures within a few seconds. We analyzed how the elements diffused at a high temperature over 1300 °C in the UHNA fiber. Then we developed a periodically heated technology with a CO₂ laser, which was able to cause the diffusion of the elements to constitute the modulations of an LPFG. With this technology, there is little damage to the outer structure of the fiber, which is different from the traditional LPFG, as it is periodically tapered. Since the LPFG itself was manufactured under high temperature, it can withstand higher temperatures than traditional LPFGs. Furthermore, the LPFG presents a higher sensitivity to high temperature due to the large amount of Ge doping, which is approximately 100 pm/°C. In addition, the LPFG shows insensitivity to the changing of the environment’s refractive index and strain.

  10. Testing of high heat flux components manufactured by ENEA for ITER divertor

    International Nuclear Information System (INIS)

    Visca, Eliseo; Escourbiac, F.; Libera, S.; Mancini, A.; Mazzone, G.; Merola, M.; Pizzuto, A.

    2009-01-01

    ENEA is involved in the International Thermonuclear Experimental Reactor (ITER) R and D activities and in particular in the manufacturing of high heat flux plasma-facing components, such as the divertor targets. During the last years ENEA has manufactured actively cooled mock-ups by using different technologies, namely brazing, diffusion bonding and HIPping. A new manufacturing process that combines two main techniques PBC (Pre-Brazed Casting) and the HRP (Hot Radial Pressing) has been set up and widely tested. A full monoblock medium scale vertical target, having a straight CFC armoured part and a curved W armoured part, was manufactured using this process. The ultrasonic method was used for the non-destructive examinations performed during the manufacturing of the component, from the monoblock preparation up to the final mock-up assembling. The component was also examined by thermography on SATIR facility (CEA, France), afterwards it was thermal fatigue tested at FE200 (200 kW electron beam facility, CEA/AREVA France). The successful results of the thermal fatigue testing performed according the ITER requirements (10 MW/m 2 , 3000 cycles of 10 s on both CFC and W part, then 20/15 MW/m 2 , 2000 cycles of 10 s on CFC/W part, respectively) have confirmed that the developed process can be considerate a candidate for the manufacturing of monoblock divertor components. Furthermore, a 35-MW/m 2 Critical Heat Flux was measured at relevant thermal-hydraulics conditions at the end of the testing campaign. This paper reports the manufacturing route, the thermal fatigue testing results, the pre and post non-destructive examination and the destructive examination performed on the ITER vertical target medium scale mock-up. These activities were performed in the frame of EFDA contracts (04-1218 with CEA, 93-851 JN with AREVA and 03-1054 with ENEA).

  11. Highly Manufacturable Deep (Sub-Millimeter) Etching Enabled High Aspect Ratio Complex Geometry Lego-Like Silicon Electronics.

    Science.gov (United States)

    Ghoneim, Mohamed Tarek; Hussain, Muhammad Mustafa

    2017-04-01

    A highly manufacturable deep reactive ion etching based process involving a hybrid soft/hard mask process technology shows high aspect ratio complex geometry Lego-like silicon electronics formation enabling free-form (physically flexible, stretchable, and reconfigurable) electronic systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Highly Manufacturable Deep (Sub-Millimeter) Etching Enabled High Aspect Ratio Complex Geometry Lego-Like Silicon Electronics

    KAUST Repository

    Ghoneim, Mohamed T.

    2017-02-01

    A highly manufacturable deep reactive ion etching based process involving a hybrid soft/hard mask process technology shows high aspect ratio complex geometry Lego-like silicon electronics formation enabling free-form (physically flexible, stretchable, and reconfigurable) electronic systems.

  13. Ductile failure analysis of high strength steel in hot forming based on micromechanical damage model

    Directory of Open Access Journals (Sweden)

    Ying Liang

    2016-01-01

    Full Text Available The damage evolution of high strength steel at elevated temperature is investigated by using the Gurson-Tvergaard-Needleman (GTN model. A hybrid method integrated thermal tensile test and numerical technique is employed to identify the damage parameters. The analysis results show that the damage parameters are different at different temperature as the variation of tested material microstructure. Furthermore, the calibrated damage parameters are implemented to simulate a bugling forming at elevated temperature. The experimental results show the availability of GTN damage model in analyzing sheet formability in hot forming.

  14. Strategic project selection based on evidential reasoning approach for high-end equipment manufacturing industry

    Directory of Open Access Journals (Sweden)

    Lu Guangyan

    2017-01-01

    Full Text Available With the rapid development of science and technology, emerging information technologies have significantly changed the daily life of people. In such context, strategic project selection for high-end equipment manufacturing industries faces more and more complexities and uncertainties with the consideration of several complex criteria. For example, a group of experts rather than a single expert should be invited to select strategic project for high-end equipment manufacturing industries and the experts may feel difficulty to express their preferences towards different strategic projects due to their limited cognitive capabilities. In order to handle these complexities and uncertainties, the criteria framework of strategic project selection is firstly constructed based on the characteristics of high-end equipment manufacturing industries and then evidential reasoning (ER approach is introduced in this paper to help experts express their uncertain preferences and aggregate these preferences to generate an appropriate strategic project. A real case of strategic project selection in a high-speed train manufacturing enterprise is investigated to demonstrate the validity of the ER approach in solving strategic project selection problem.

  15. Lean Production Control at a High-Variety, Low-Volume Parts Manufacturer

    NARCIS (Netherlands)

    Bokhorst, Jos A. C.; Slomp, Jannes

    2010-01-01

    Eaton Electric General Supplies, a parts manufacturing unit that supplies parts for Eaton's electrical business unit, implemented several lean control elements in its high-variety, low-volume production units. These control elements include a constant work-in-process mechanism to limit and control

  16. Adaptive Process Controls and Ultrasonics for High Temperature PEM MEA Manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Walczyk, Daniel F. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2015-08-26

    The purpose of this 5-year DOE-sponsored project was to address major process bottlenecks associated with fuel cell manufacturing. New technologies were developed to significantly reduce pressing cycle time for high temperature PEM membrane electrode assembly (MEA) through the use of novel, robust ultrasonic (U/S) bonding processes along with low temperature (<100°C) PEM MEAs. In addition, greater manufacturing uniformity and performance was achieved through (a) an investigation into the causes of excessive variation in ultrasonically and thermally bonded MEAs using more diagnostics applied during the entire fabrication and cell build process, and (b) development of rapid, yet simple quality control measurement techniques for use by industry.

  17. The high integrity design and manufacture of the Heysham II/Torness gas baffle

    International Nuclear Information System (INIS)

    Armor, J.; Day, B.V.; White, C.M.

    1985-01-01

    The AGR design used on the Heysham II and Torness power stations requires a gas baffle which is essentially a steel pressure vessel for which one can demonstrate a high degree of integrity. The design, analytical, manufacturing, erection and testing processes which were undertaken to achieve the standard required of the completed assembly are discussed. To this end the vessels were manufactured in purpose-made shops and transported to site, leaving a minimum amount of work to be undertaken at site. Subsequent evaluation has shown a very low probability of failure compared with conventional steel pressure vessels. (author)

  18. An application of impediography to the high sensitivity and high resolution identification of structural damage

    International Nuclear Information System (INIS)

    Zhao, L; Yang, J; Semperlotti, F; Wang, K W

    2015-01-01

    In this study we explore the use of impediographic techniques to perform damage detection in plate-like metal structures. Impediography relies on the piezo-resistive coupling of the host structure to reconstruct high sensitivity and high resolution maps of the internal electrical conductivity. By exploiting localized strain perturbations generated via focused acoustic waves, the piezo-resistive coupling allows extracting a set of linearly independent boundary voltage data that drastically reduces the ill-conditioning of the inverse problem, therefore increasing the performance. The localized perturbation is achieved by leveraging the concept of frequency selective structure (FSS), that is a dynamically tailored structural element enabling the required acoustic focusing via vibration localization. Based on the FSS approach, the impediographic technique is numerically tested to investigate the performance of the combined approach for structural damage detection. The effects of practical implementation issues, such as limited perturbations and limited boundary data, are also explored. (paper)

  19. The design of reconfigurable assembly stations for high variety and mass customisation manufacturing

    Directory of Open Access Journals (Sweden)

    Padayachee, Jared

    2013-11-01

    Full Text Available The economical production of mass customised and high variety goods is a challenge facing modern manufacturers. This challenge is being addressed, in part, by the on-going development of technologies that facilitate the manufacturing of these goods. Existing technologies require either excessive inbuilt flexibility or frequent changes to the machine set up to provide the manufacturing functions required for the customisation process. This paper presents design principles for automated assembly stations within the scope of mass customisation. Design principles are presented that minimise the hardware and operating complexities of assembly stations, allowing stations to be easily automated for concurrent mixed model assembly with a First In First Out (FIFO scheduling policy. A reconfigurable assembly station is developed to demonstrate how the proposed design methods simplify the creation and operation of an assembly station for a product family of flashlights.

  20. Development and manufacture of a Nb3Sn superconductor for the high-field test facility

    International Nuclear Information System (INIS)

    Scanlan, R.M.; Cornish, D.N.; Spencer, C.R.; Gregory, E.; Adam, E.

    1981-01-01

    The High-Field Test Facility (HFTF) project has two primary goals. The first is to establish manufacturing capability for a Nb 3 Sn conductor suitable for use in a mirror fusion coil. The second is to provide a test facility for evaluating other fusion conductor designs at high fields. This paper describes some of the problems encountered and the solutions devised in working toward the first goal. Construction of the test facility coils will be described in a subsequent paper

  1. Robust optimization of the laser induced damage threshold of dielectric mirrors for high power lasers.

    Science.gov (United States)

    Chorel, Marine; Lanternier, Thomas; Lavastre, Éric; Bonod, Nicolas; Bousquet, Bruno; Néauport, Jérôme

    2018-04-30

    We report on a numerical optimization of the laser induced damage threshold of multi-dielectric high reflection mirrors in the sub-picosecond regime. We highlight the interplay between the electric field distribution, refractive index and intrinsic laser induced damage threshold of the materials on the overall laser induced damage threshold (LIDT) of the multilayer. We describe an optimization method of the multilayer that minimizes the field enhancement in high refractive index materials while preserving a near perfect reflectivity. This method yields a significant improvement of the damage resistance since a maximum increase of 40% can be achieved on the overall LIDT of the multilayer.

  2. Design of a high power TM01 mode launcher optimized for manufacturing by milling

    Energy Technology Data Exchange (ETDEWEB)

    Dal Forno, Massimo [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-12-15

    Recent research on high-gradient rf acceleration found that hard metals, such as hard copper and hard copper-silver, have lower breakdown rate than soft metals. Traditional high-gradient accelerating structures are manufactured with parts joined by high-temperature brazing. The high temperature used in brazing makes the metal soft; therefore, this process cannot be used to manufacture structures out of hard metal alloys. In order to build the structure with hard metals, the components must be designed for joining without high-temperature brazing. One method is to build the accelerating structures out of two halves, and join them by using a low-temperature technique, at the symmetry plane along the beam axis. The structure has input and output rf power couplers. We use a TM01 mode launcher as a rf power coupler, which was introduced during the Next Linear Collider (NLC) work. The part of the mode launcher will be built in each half of the structure. This paper presents a novel geometry of a mode launcher, optimized for manufacturing by milling. The coupler was designed for the CERN CLIC working frequency f = 11.9942 GHz; the same geometry can be scaled to any other frequency.

  3. A high performance, high precision, low cost rapid prototyping and manufacturing technology

    OpenAIRE

    Viacheslav R. Shulunov

    2014-01-01

    A novel roll powder sintering (RPS) technology is proposed for processing real plastic, ceramic, metal and other 3-D objects 1m³ (or more) in volume directly from a CAD model within several hours. The breakthrough advantages of the technology are compared to the dominant rapid prototyping and manufacturing (RP&M) processes that are currently on the market.

  4. Vacuum ultra-violet damage and damage mitigation for plasma processing of highly porous organosilicate glass dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Marneffe, J.-F. de, E-mail: marneffe@imec.be; Lukaszewicz, M.; Porter, S. B.; Vajda, F.; Rutigliani, V.; Verdonck, P.; Baklanov, M. R. [IMEC v.z.w., 3001 Leuven (Belgium); Zhang, L.; Heyne, M.; El Otell, Z.; Krishtab, M. [IMEC v.z.w., 3001 Leuven (Belgium); Department of Chemistry, KULeuven, 3001 Leuven (Belgium); Goodyear, A.; Cooke, M. [Oxford Instruments Plasma Technology, BS49 4AP Bristol (United Kingdom)

    2015-10-07

    Porous organosilicate glass thin films, with k-value 2.0, were exposed to 147 nm vacuum ultra-violet (VUV) photons emitted in a Xenon capacitive coupled plasma discharge. Strong methyl bond depletion was observed, concomitant with a significant increase of the bulk dielectric constant. This indicates that, besides reactive radical diffusion, photons emitted during plasma processing do impede dielectric properties and therefore need to be tackled appropriately during patterning and integration. The detrimental effect of VUV irradiation can be partly suppressed by stuffing the low-k porous matrix with proper sacrificial polymers showing high VUV absorption together with good thermal and VUV stability. In addition, the choice of an appropriate hard-mask, showing high VUV absorption, can minimize VUV damage. Particular processing conditions allow to minimize the fluence of photons to the substrate and lead to negligible VUV damage. For patterned structures, in order to reduce VUV damage in the bulk and on feature sidewalls, the combination of both pore stuffing/material densification and absorbing hard-mask is recommended, and/or the use of low VUV-emitting plasma discharge.

  5. Bacterial natural transformation by highly fragmented and damaged DNA

    DEFF Research Database (Denmark)

    Overballe-Petersen, Søren; Harms, Klaus; Orlando, Ludovic Antoine Alexandre

    2013-01-01

    for microbes, but not as potential substrate for bacterial evolution. Here, we show that fragmented DNA molecules (≥20 bp) that additionally may contain abasic sites, cross-links, or miscoding lesions are acquired by the environmental bacterium Acinetobacter baylyi through natural transformation. With uptake......DNA molecules are continuously released through decomposition of organic matter and are ubiquitous in most environments. Such DNA becomes fragmented and damaged (often DNA is recognized as nutrient source...... of DNA from a 43,000-y-old woolly mammoth bone, we further demonstrate that such natural transformation events include ancient DNA molecules. We find that the DNA recombination is RecA recombinase independent and is directly linked to DNA replication. We show that the adjacent nucleotide variations...

  6. High-shear granulation as a manufacturing method for cocrystal granules

    DEFF Research Database (Denmark)

    Rehder, Sönke; Christensen, Niels Peter Aae; Rantanen, Jukka

    2013-01-01

    and the respective excipients). The drug release was slightly decreased by cocrystal formation, most likely due to the lower solubility of the cocrystal. In the presence of calcium hydrogenphosphate however, no influence of cocrystal formation on either compactability or on drug release were observed, compared...... with the reference tablets. It was concluded that high-shear wet granulation is a valuable, however complex, manufacturing method for cocrystals. Cocrystal formation may influence compactability and drug release and thus affect drug performance and should be investigated during pre-formulation.......Cocrystal formation allows the tailoring of physicochemical as well as of mechanical properties of an API. However, there is a lack of large-scale manufacturing methods of cocrystals. Therefore, the objective of this work was to examine the suitability of high-shear wet granulation...

  7. Manufacturing of highly integrated mechatronic modules by using the technology of embedding stereolithography

    Science.gov (United States)

    Rechtenwald, Thomas; Frick, Thomas; Schmidt, Michael

    The embedding stereolithography is an additive, hybrid process, which allows the construction of highly integrated 3D assemblies for the use in automotive applications. The flexible process of stereolithography is combined with the embedding of functional components and supplemented by the additive manufacturing of electrical or optical conductive structures. This combination of sub-processes implies a high potential regarding the obtainable integration density of mechatronical modules. This work considers basic restrictions, which limit the mechanical stability of the manufactured modules by calculating the superposition of residual and external stress using a thermo-mechanical finite element model and develops a procedure to qualify stereolithography matrix materials for the process of the embedding stereolithography.

  8. Creating Value for Customer in Business Networks of High-Tech Goods Manufacturers

    Directory of Open Access Journals (Sweden)

    Joanna Wiechoczek

    2016-01-01

    Full Text Available The main paper goal is to recognize the category of value for customer with respect to high-tech products, and to propose a model of creation of this value in business networks established by manufacturers. The research methods include critical analysis of the literature, documentation method, as well as the case research method and observation method. The results of the research proved that the value offered to buyers is characterized by growing multidimensionality which results in increasing complexity of the creation process of this value by their manufacturers. Due to the fact that they do not have complex skills and resources to create the value independently, they form business networks. These networks include increasingly larger group of entities, in which the importance of individual cooperants is highly diversified.

  9. A Modified Fatigue Damage Model for High-Cycle Fatigue Life Prediction

    Directory of Open Access Journals (Sweden)

    Meng Wang

    2016-01-01

    Full Text Available Based on the assumption of quasibrittle failure under high-cycle fatigue for the metal material, the damage constitutive equation and the modified damage evolution equation are obtained with continuum damage mechanics. Then, finite element method (FEM is used to describe the failure process of metal material. The increment of specimen’s life and damage state can be researched using damage mechanics-FEM. Finally, the lifetime of the specimen is got at the given stress level. The damage mechanics-FEM is inserted into ABAQUS with subroutine USDFLD and the Python language is used to simulate the fatigue process of titanium alloy specimens. The simulation results have a good agreement with the testing results under constant amplitude loading, which proves the accuracy of the method.

  10. Manufacture of high-strength composite materials from prepregs prepared by radiation processing

    International Nuclear Information System (INIS)

    Laricheva, V.P.; Korotkij, A.F.

    2008-01-01

    Scientific principles of the manufacture of high-strength heat-resistant polymer composite materials with the successive ionizing-radiation and heat treatment (via the step of long-lived prepregs) were developed. Methods for the selection of components for the preparation of long-lived prepregs, as well as for the determination of the optimal curing conditions, were proposed. The mechanical properties of the materials were studied [ru

  11. Two scale damage model and related numerical issues for thermo-mechanical high cycle fatigue

    International Nuclear Information System (INIS)

    Desmorat, R.; Kane, A.; Seyedi, M.; Sermage, J.P.

    2007-01-01

    On the idea that fatigue damage is localized at the microscopic scale, a scale smaller than the mesoscopic one of the Representative Volume Element (RVE), a three-dimensional two scale damage model has been proposed for High Cycle Fatigue applications. It is extended here to aniso-thermal cases and then to thermo-mechanical fatigue. The modeling consists in the micro-mechanics analysis of a weak micro-inclusion subjected to plasticity and damage embedded in an elastic meso-element (the RVE of continuum mechanics). The consideration of plasticity coupled with damage equations at micro-scale, altogether with Eshelby-Kroner localization law, allows to compute the value of microscopic damage up to failure for any kind of loading, 1D or 3D, cyclic or random, isothermal or aniso-thermal, mechanical, thermal or thermo-mechanical. A robust numerical scheme is proposed in order to make the computations fast. A post-processor for damage and fatigue (DAMAGE-2005) has been developed. It applies to complex thermo-mechanical loadings. Examples of the representation by the two scale damage model of physical phenomena related to High Cycle Fatigue are given such as the mean stress effect, the non-linear accumulation of damage. Examples of thermal and thermo-mechanical fatigue as well as complex applications on real size testing structure subjected to thermo-mechanical fatigue are detailed. (authors)

  12. Automated packaging platform for low-cost high-performance optical components manufacturing

    Science.gov (United States)

    Ku, Robert T.

    2004-05-01

    Delivering high performance integrated optical components at low cost is critical to the continuing recovery and growth of the optical communications industry. In today's market, network equipment vendors need to provide their customers with new solutions that reduce operating expenses and enable new revenue generating IP services. They must depend on the availability of highly integrated optical modules exhibiting high performance, small package size, low power consumption, and most importantly, low cost. The cost of typical optical system hardware is dominated by linecards that are in turn cost-dominated by transmitters and receivers or transceivers and transponders. Cost effective packaging of optical components in these small size modules is becoming the biggest challenge to be addressed. For many traditional component suppliers in our industry, the combination of small size, high performance, and low cost appears to be in conflict and not feasible with conventional product design concepts and labor intensive manual assembly and test. With the advent of photonic integration, there are a variety of materials, optics, substrates, active/passive devices, and mechanical/RF piece parts to manage in manufacturing to achieve high performance at low cost. The use of automation has been demonstrated to surpass manual operation in cost (even with very low labor cost) as well as product uniformity and quality. In this paper, we will discuss the value of using an automated packaging platform.for the assembly and test of high performance active components, such as 2.5Gb/s and 10 Gb/s sources and receivers. Low cost, high performance manufacturing can best be achieved by leveraging a flexible packaging platform to address a multitude of laser and detector devices, integration of electronics and handle various package bodies and fiber configurations. This paper describes the operation and results of working robotic assemblers in the manufacture of a Laser Optical Subassembly

  13. Innovative High-Performance Deposition Technology for Low-Cost Manufacturing of OLED Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Scott, David; Hamer, John

    2017-06-30

    In this project, OLEDWorks developed and demonstrated the innovative high-performance deposition technology required to deliver dramatic reductions in the cost of manufacturing OLED lighting in production equipment. The current high manufacturing cost of OLED lighting is the most urgent barrier to its market acceptance. The new deposition technology delivers solutions to the two largest parts of the manufacturing cost problem – the expense per area of good product for organic materials and for the capital cost and depreciation of the equipment. Organic materials cost is the largest expense item in the bill of materials and is predicted to remain so through 2020. The high-performance deposition technology developed in this project, also known as the next generation source (NGS), increases material usage efficiency from 25% found in current Gen2 deposition technology to 60%. This improvement alone results in a reduction of approximately $25/m2 of good product in organic materials costs, independent of production volumes. Additionally, this innovative deposition technology reduces the total depreciation cost from the estimated value of approximately $780/m2 of good product for state-of-the-art G2 lines (at capacity, 5-year straight line depreciation) to $170/m2 of good product from the OLEDWorks production line.

  14. Additive manufacturing of metals: a brief review of the characteristic microstructures and properties of steels, Ti-6Al-4V and high-entropy alloys

    Science.gov (United States)

    Gorsse, Stéphane; Hutchinson, Christopher; Gouné, Mohamed; Banerjee, Rajarshi

    2017-01-01

    Abstract We present a brief review of the microstructures and mechanical properties of selected metallic alloys processed by additive manufacturing (AM). Three different alloys, covering a large range of technology readiness levels, are selected to illustrate particular microstructural features developed by AM and clarify the engineering paradigm relating process–microstructure–property. With Ti-6Al-4V the emphasis is placed on the formation of metallurgical defects and microstructures induced by AM and their role on mechanical properties. The effects of the large in-built dislocation density, surface roughness and build atmosphere on mechanical and damage properties are discussed using steels. The impact of rapid solidification inherent to AM on phase selection is highlighted for high-entropy alloys. Using property maps, published mechanical properties of additive manufactured alloys are graphically summarized and compared to conventionally processed counterparts. PMID:28970868

  15. Additive Manufacturing of Multifunctional Components Using High Density Carbon Nanotube Yarn Filaments

    Science.gov (United States)

    Gardner, John M.; Sauti, Godfrey; Kim, Jae-Woo; Cano, Roberto J.; Wincheski, Russell A.; Stelter, Christopher J.; Grimsley, Brian W.; Working, Dennis C.; Siochi, Emilie J.

    2016-01-01

    Additive manufacturing allows for design freedom and part complexity not currently attainable using traditional manufacturing technologies. Fused Filament Fabrication (FFF), for example, can yield novel component geometries and functionalities because the method provides a high level of control over material placement and processing conditions. This is achievable by extrusion of a preprocessed filament feedstock material along a predetermined path. However if fabrication of a multifunctional part relies only on conventional filament materials, it will require a different material for each unique functionality printed into the part. Carbon nanotubes (CNTs) are an attractive material for many applications due to their high specific strength as well as good electrical and thermal conductivity. The presence of this set of properties in a single material presents an opportunity to use one material to achieve multifunctionality in an additively manufactured part. This paper describes a recently developed method for processing continuous CNT yarn filaments into three-dimensional articles, and summarizes the mechanical, electrical, and sensing performance of the components fabricated in this way.

  16. A new approach for high performance fiber manufacturing via simultaneous fiber spinning and UV initiated polymerization

    Science.gov (United States)

    Ellison, Chris

    Synthetic fibers have been manufactured for decades using solvents or heat to reduce the viscosity of pre-formed polymers and promote drawing. However, nature has engineered spiders and silkworms with benign ways of making silk fibers with high strength and toughness. Conceptually, their approach of chemically linking small functional units (i.e., proteins) into long chain molecules and solid fibrillar structures ``on-demand'' is fundamentally different from current synthetic fiber manufacturing methods. Drawing inspiration from nature, a method will be described that uses light to trigger a thiol-ene photopolymerization to rapidly transform reactive liquid mixtures into solid thread-like structures as they are forced out of a capillary at high speeds. Besides being manufactured without using solvents/volatile components or heat, these fibers are mechanically robust and have excellent chemical and thermal stability due to their crosslinked nature. During processing, the balance between curing kinetics, fiber flight time, and monomer mixture viscoelasticity is essential for the formation of defect free fibers. This work focuses on developing a universal operating diagram to show how the intricate interplay of gel time, flight time, and fluid relaxation time leads to the formation of uniform fibers and other undesirable fiber morphologies such as beads-on-string, fused fibers, non-uniform fibers, and droplets. This predictive capability enables adaptation of this spinning concept to all existing fiber spinning platforms, and customization of monomer formulations to target desired properties.

  17. An Integrated Model for Supplier Selection for a High-Tech Manufacturer

    Science.gov (United States)

    Lee, Amy H. I.; Kang, He-Yau; Lin, Chun-Yu

    2011-11-01

    Global competitiveness has become the biggest concern of manufacturing companies, especially in high-tech industries. Improving competitive edges in an environment with rapidly changing technological innovations and dynamic customer needs is essential for a firm to survive and to acquire a decent profit. Thus, the introduction of successful new products is a source of new sales and profits and is a necessity in the intense competitive international market. After a product is developed, a firm needs the cooperation of upstream suppliers to provide satisfactory components and parts for manufacturing final products. Therefore, the selection of suitable suppliers has also become a very important decision. In this study, an analytical approach is proposed to select the most appropriate critical-part suppliers in order to maintain a high reliability of the supply chain. A fuzzy analytic network process (FANP) model, which incorporates the benefits, opportunities, costs and risks (BOCR) concept, is constructed to evaluate various aspects of suppliers. The proposed model is adopted in a TFT-LCD manufacturer in Taiwan in evaluating the expected performance of suppliers with respect to each important factor, and an overall ranking of the suppliers can be generated as a result.

  18. Manufacturing and material properties of forgings for reactor pressure vessel of high temperature engineering test reactor

    International Nuclear Information System (INIS)

    Sato, I.; Suzuki, K.

    1994-01-01

    For the reactor pressure vessel (RPV) of high temperature engineering test reactor (HTTR) which has been developed by Japan Atomic Energy Research Institute (JAERI), 2 1/4Cr-1Mo steel is used first in the world. Material confirmation test has been carried out to demonstrate good applicability of forged low Si 2 1/4Cr-1Mo steel to the RPV of HTTR. Recently, JSW has succeeded in the manufacturing of large size ring forgings and large size forged cover dome integrated with nozzles for stand pipe for the RPV. This paper describes the results of the material confirmation test as well as the manufacturing and material properties of the large forged cover dome integrated with nozzles for stand pipe. (orig.)

  19. Advanced technologies for manufacturing high strength sour grade UOE line pipe

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Kenji; Omura, Tomohiko; Takahashi, Nobuaki; Minato, Izuru; Yamamoto, Akio [Sumitomo Metal Industries, Ltd., Kashima, (Japan)

    2010-07-01

    A new kind of high strength pipeline has been manufactured for sour service in offshore pipelines. This paper first presents a review of developments in manufacturing technology to improve sour resistance. This was particularly the case with Grade UOE line pipe. The improvement was achieved by optimizing the continuous casting process, monitoring the shape of inclusions (such as MnS, CaS, Al2O3, CaO-Al2O3) and decreasing coarse precipitates (Nb(C,N), TiN). The study then used the HIC evaluation method to determine hydrogen induced cracking (HIC) resistance of the material and HAZ test for sulfide stress cracking (SSC) resistance. The evaluation of the NACE TM0284 solution A showed that these pipelines are able to resist severe sour conditions because of good HIC and SSC resistance. Optimizing others components like alloying elements and the ACC process would improve sour resistance in future applications.

  20. Improvement of microstructure and mechanical properties of high dense SiC ceramics manufactured by high-speed hot pressing

    International Nuclear Information System (INIS)

    Voyevodin, V.; Sayenko, S.; Lobach, K.; Tarasov, R.; Zykova, A.; Svitlychnyi, Ye.; Surkov, A.; Abelentsev, V.; Ghaemi, H.; Szkodo, M.; Gajowiec, G.; Kmiec, M.; Antoszkiewicz, M.

    2017-01-01

    Non-oxide ceramics possess high physical-mechanical properties, corrosion and radiation resistance, which can be used as a protective materials for radioactive wastes disposal. The aim of the present study was the manufacturing of high density SiC ceramics with advanced physical and mechanical parameters. The high performance on the properties of produced ceramics was determined by the dense and monolithic structure. The densified silicon carbide samples possessed good mechanical strength, with a high Vickers micro hardness up to 28.5 GPa.

  1. On the development of high quality NiTi shape memory and pseudoelastic parts by additive manufacturing

    International Nuclear Information System (INIS)

    Haberland, Christoph; Elahinia, Mohammad; Walker, Jason M; Meier, Horst; Frenzel, Jan

    2014-01-01

    Additive manufacturing provides an attractive processing method for nickel–titanium (NiTi) shape memory and pseudoelastic parts. In this paper, we show how the additive manufacturing process affects structural and functional properties of additively manufactured NiTi and how the process parameter set-up can be optimized to produce high quality NiTi parts and components. Comparisons of shape recovery due to shape memory and pseudoelasticity in additively manufactured and commercial NiTi exhibit promising potential for this innovative processing method. (paper)

  2. Adoption of High Performance Computational (HPC) Modeling Software for Widespread Use in the Manufacture of Welded Structures

    Energy Technology Data Exchange (ETDEWEB)

    Brust, Frederick W. [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Punch, Edward F. [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Twombly, Elizabeth Kurth [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Kalyanam, Suresh [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Kennedy, James [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Hattery, Garty R. [Engineering Mechanics Corporation of Columbus, Columbus, OH (United States); Dodds, Robert H. [Professional Consulting Services, Inc., Lisle, IL (United States); Mach, Justin C [Caterpillar, Peoria, IL (United States); Chalker, Alan [Ohio Supercomputer Center (OSC), Columbus, OH (United States); Nicklas, Jeremy [Ohio Supercomputer Center (OSC), Columbus, OH (United States); Gohar, Basil M [Ohio Supercomputer Center (OSC), Columbus, OH (United States); Hudak, David [Ohio Supercomputer Center (OSC), Columbus, OH (United States)

    2016-12-30

    . Through VFT®, manufacturing companies can avoid costly design changes after fabrication. This leads to the concept of joint design/fabrication where these important disciplines are intimately linked to minimize fabrication costs. Finally service performance (such as fatigue, corrosion, and fracture/damage) can be improved using this product. Emc2’s DOE SBIR Phase II effort successfully adapted VFT® to perform efficiently in an HPC environment independent of commercial software on a platform to permit easy and cost effective access to the code. This provides the key for SMEs to access this sophisticated and proven methodology that is quick, accurate, cost effective and available “on-demand” to address weld-simulation and fabrication problems prior to manufacture. In addition, other organizations, such as Government agencies and large companies, may have a need for spot use of such a tool. The open source code, WARP3D, a high performance finite element code used in fracture and damage assessment of structures, was significantly modified so computational weld problems can be solved efficiently on multiple processors and threads with VFT®. The thermal solver for VFT®, based on a series of closed form solution approximations, was extensively enhanced for solution on multiple processors greatly increasing overall speed. In addition, the graphical user interface (GUI) was re-written to permit SMEs access to an HPC environment at the Ohio Super Computer Center (OSC) to integrate these solutions with WARP3D. The GUI is used to define all weld pass descriptions, number of passes, material properties, consumable properties, weld speed, etc. for the structure to be modeled. The GUI was enhanced to make it more user-friendly so that non-experts can perform weld modeling. Finally, an extensive outreach program to market this capability to fabrication companies was performed. This access will permit SMEs to perform weld modeling to improve their competitiveness at a

  3. Design for manufacturing and assembly key performance indicators to support high-speed product development

    DEFF Research Database (Denmark)

    Thompson, Mary Kathryn; Juel Jespersen, Ida Kirstine; Kjærgaard, Thomas

    2018-01-01

    Design for Manufacturing and Assembly (DfMA) has great potential for minimizing late engineering changes (ECs) that impede high-speed product development and delay time-to-profit. However, our understanding of DfMA and its implementation in industry is still incomplete. This paper presents...... an industrial case study on late ECs in high-speed product development and compares the results to other examples from the literature. It then proposes a framework with sets of key performance indicators (KPIs) to measure and improve producability and product quality throughout the product development process....

  4. Application of laser additive manufacturing to produce dies for aluminium high pressure die casting

    CSIR Research Space (South Africa)

    Pereira, MFVT

    2012-07-01

    Full Text Available through immersion in liquid aluminium. The dipping cycle closely resembles the heating and cooling cycle of a typical aluminium die under casting conditions. The suitability of any LAM technology, that can produce fully dense metallic components... cost vs wrought manufactured 5.2 1,7 2. 2 Average cost Very High Medium High Table 3: Processing and finishing costs of test coupons 3.1 Cyclic Immersion in Molten Aluminium Figure 3 below shows the testing apparatus developed to simulate...

  5. Use of high voltage electron microscope to simulate radiation damage by neutrons

    International Nuclear Information System (INIS)

    Mayer, R.M.

    1976-01-01

    The use of the high voltage electron microscope to simulate radiation damage by neutrons is briefly reviewed. This information is important in explaining how alloying affects void formation during neutron irradiation

  6. Analysis of high resolution scatter images from laser damage experiments performed on KDP

    International Nuclear Information System (INIS)

    Runkel, M.; Woods, B.; Yan, M.

    1996-01-01

    Interest in producing high damage threshold KH 2 PO 4 (KDP) and (D x H 1-x ) 2 PO 4 (KD*P, DKDP) for optical switching and frequency conversion applications is being driven by the system requirements for the National Ignition Facility (NIF) at Lawrence Livermore National Lab (LLNL). Historically, the path to achieving higher damage thresholds has been to improve the purity of crystal growth solutions. Application of advanced filtration technology has increased the damage threshold, but gives little insight into the actual mechanisms of laser damage. We have developed a laser scatter diagnostic to better study bulk defects and laser damage mechanisms in KDP and KD*P crystals. This diagnostic consists of a cavity doubled, kilohertz class, Nd:YLF laser (527 nm) and high dynamic range CCD camera which allows imaging of bulk scatter signals. With it, we have performed damage tests at 355 nm on four different open-quotes vintagesclose quotes of KDP crystals, concentrating on crystals produced via fast growth methods. We compare the diagnostic's resolution to LLNL's standard damage detection method of 100X darkfield microscopy and discuss its impact on damage threshold determination. We have observed the disappearance of scatter sites upon exposure to subthreshold irradiation. In contrast, we have seen scatterers appear where none previously existed. This includes isolated, large (high signal) sites as well as multiple small scatter sites which appear at fluences above 7 J/cm 2 (fine tracking). However, we have not observed a strong correlation of preexisting scatter sites and laser damage sites. We speculate on the connection between the laser-induced disappearance of scatter sites and the observed increase in damage threshold with laser conditioning

  7. Subsurface damage mechanism of high speed grinding process in single crystal silicon revealed by atomistic simulations

    International Nuclear Information System (INIS)

    Li, Jia; Fang, Qihong; Zhang, Liangchi; Liu, Youwen

    2015-01-01

    Highlights: • Molecular dynamic model of nanoscale high speed grinding of silicon workpiece has been established. • The effect of grinding speed on subsurface damage and grinding surface integrity by analyzing the chip, dislocation movement, and phase transformation during high speed grinding process are thoroughly investigated. • Subsurface damage is studied by the evolution of surface area at first time for more obvious observation on transition from ductile to brittle. • The hydrostatic stress and von Mises stress by the established analytical model are studied subsurface damage mechanism during nanoscale grinding. - Abstract: Three-dimensional molecular dynamics (MD) simulations are performed to investigate the nanoscale grinding process of single crystal silicon using diamond tool. The effect of grinding speed on subsurface damage and grinding surface integrity by analyzing the chip, dislocation movement, and phase transformation are studied. We also establish an analytical model to calculate several important stress fields including hydrostatic stress and von Mises stress for studying subsurface damage mechanism, and obtain the dislocation density on the grinding subsurface. The results show that a higher grinding velocity in machining brittle material silicon causes a larger chip and a higher temperature, and reduces subsurface damage. However, when grinding velocity is above 180 m s −1 , subsurface damage thickness slightly increases because a higher grinding speed leads to the increase in grinding force and temperature, which accelerate dislocation nucleation and motion. Subsurface damage is studied by the evolution of surface area at first time for more obvious observation on transition from ductile to brittle, that provides valuable reference for machining nanometer devices. The von Mises stress and the hydrostatic stress play an important role in the grinding process, and explain the subsurface damage though dislocation mechanism under high

  8. A high sensitivity, high throughput, automated single-cell gel electrophoresis ('Comet') DNA damage assay

    International Nuclear Information System (INIS)

    Vojnovic, B.; Barber, P.R.; Johnston, P.J.; Gregory, H.C.; Locke, R.J.

    2003-01-01

    A fully automated microscopy machine vision image capture and analysis system for the collection of data from slides of 'comets' has been developed. The novel image processing algorithms employed in delineating the 'comet head' from the 'comet tail' allow us to determine accurately very low levels of damage. In conjunction with calibrated and automated image capture methods, we are able to eliminate operator subjectivity and analyse large numbers of cells (>2500) in a short time (<1 hour). The image processing algorithm is designed to handle particularly difficult nuclei containing a high degree of structure, due to DNA clumping. We also present techniques used to extend the assay's dynamic range by removing interfering background fluorescence and to define a region of interest. If subtle biological variations are to be quantified (e.g. cell cycle dependant damage), then the use of large cell populations is dictated. Under those circumstances, the use of a fully automated system is particularly advantageous providing that the manner in which data is extracted does not introduce any inadvertent bias. In practice, it is essential that the image processing steps are geared towards the correct recognition of an acceptable cell nucleus, i.e. comet 'head'. We acknowledge the financial support of CRUK, Programme Grant C133/A1812 - SP 2195-01/02 and the US Department of Energy Low Dose Radiation Research Program grant DE-FG07-99ER62878

  9. Full-length high-temperature severe fuel damage test No. 2

    International Nuclear Information System (INIS)

    Hesson, G.M.; Lombardo, N.J.; Pilger, J.P.; Rausch, W.N.; King, L.L.; Hurley, D.E.; Parchen, L.J.; Panisko, F.E.

    1993-09-01

    Hazardous conditions associated with performing the Full-Length High- Temperature (FLHT). Severe Fuel Damage Test No. 2 experiment have been analyzed. Major hazards that could cause harm or damage are (1) radioactive fission products, (2) radiation fields, (3) reactivity changes, (4) hydrogen generation, (5) materials at high temperature, (6) steam explosion, and (7) steam pressure pulse. As a result of this analysis, it is concluded that with proper precautions the FLHT- 2 test can be safely conducted

  10. Manufacturing and thermomechanical testing of actively cooled all beryllium high heat flux test pieces

    International Nuclear Information System (INIS)

    Vasiliev, N.N.; Sokolov, Yu.A.; Shatalov, G.E.

    1995-01-01

    One of the problems affiliated to ITER high heat flux elements development is a problem of interface of beryllium protection with heat sink routinely made of copper alloys. To get rid of this problem all beryllium elements could be used as heat receivers in places of enhanced thermal loads. In accordance with this objectives four beryllium test pieces of two types have been manufactured in open-quotes Institute of Berylliumclose quotes for succeeding thermomechanical testing. Two of them were manufactured in accordance with JET team design; they are round open-quotes hypervapotron typeclose quotes test pieces. Another two ones are rectangular test sections with a twisted tape installed inside of the circular channel. Preliminary stress-strain analysis have been performed for both type of the test pieces. Hypervapotrons have been shipped to JET where they were tested on JET test bed. Thermomechanical testing of pieces of the type of open-quotes swirl tape inside of tubeclose quotes have been performed on Kurchatov Institute test bed. Chosen beryllium grade properties, some details of manufacturing, results of preliminary stress-strain analysis and thermomechanical testing of the test pieces open-quotes swirl tape inside of tubeclose quotes type are given in this report

  11. Recent Advancements in DNA Damage-Transcription Crosstalk and High-Resolution Mapping of DNA Breaks.

    Science.gov (United States)

    Vitelli, Valerio; Galbiati, Alessandro; Iannelli, Fabio; Pessina, Fabio; Sharma, Sheetal; d'Adda di Fagagna, Fabrizio

    2017-08-31

    Until recently, DNA damage arising from physiological DNA metabolism was considered a detrimental by-product for cells. However, an increasing amount of evidence has shown that DNA damage could have a positive role in transcription activation. In particular, DNA damage has been detected in transcriptional elements following different stimuli. These physiological DNA breaks are thought to be instrumental for the correct expression of genomic loci through different mechanisms. In this regard, although a plethora of methods are available to precisely map transcribed regions and transcription start sites, commonly used techniques for mapping DNA breaks lack sufficient resolution and sensitivity to draw a robust correlation between DNA damage generation and transcription. Recently, however, several methods have been developed to map DNA damage at single-nucleotide resolution, thus providing a new set of tools to correlate DNA damage and transcription. Here, we review how DNA damage can positively regulate transcription initiation, the current techniques for mapping DNA breaks at high resolution, and how these techniques can benefit future studies of DNA damage and transcription.

  12. High-Density Plasma-Induced Etch Damage of GaN

    International Nuclear Information System (INIS)

    Baca, A.G.; Han, J.; Lester, L.F.; Pearton, S.J.; Ren, F.; Shul, R.J.; Willison, C.G.; Zhang, L.; Zolper, J.C.

    1999-01-01

    Anisotropic, smooth etching of the group-III nitrides has been reported at relatively high rates in high-density plasma etch systems. However, such etch results are often obtained under high de-bias and/or high plasma flux conditions where plasma induced damage can be significant. Despite the fact that the group-III nitrides have higher bonding energies than more conventional III-V compounds, plasma-induced etch damage is still a concern. Attempts to minimize such damage by reducing the ion energy or increasing the chemical activity in the plasma often result in a loss of etch rate or anisotropy which significantly limits critical dimensions and reduces the utility of the process for device applications requiring vertical etch profiles. It is therefore necessary to develop plasma etch processes which couple anisotropy for critical dimension and sidewall profile control and high etch rates with low-damage for optimum device performance. In this study we report changes in sheet resistance and contact resistance for n- and p-type GaN samples exposed to an Ar inductively coupled plasma (ICP). In general, plasma-induced damage was more sensitive to ion bombardment energies as compared to plasma flux. In addition, p-GaN was typically more sensitive to plasma-induced damage as compared to n-GaN

  13. Additive Manufacturing of Hierarchical Multi-Phase High-Entropy Alloys for Nuclear Component

    Energy Technology Data Exchange (ETDEWEB)

    Li, Nan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-10

    In recent years, high entropy alloys (HEAs), composed of four or more metallic elements mixed in equal or near equal atomic percent, have attracted significant attention due to their excellent mechanical properties and good corrosion resistance. They show significant promise as candidates for high temperature fission and fusion structural applications. However, the conventional synthesis methods are unlikely to present an industrially suitable route for the production and use of HEAs. Recognizing rapidly evolving additive manufacturing (AM) techniques, the goal of this proposal is to optimize the AM process to fabricate HEAs with predesigned chemical compositions and phase morphologies for nuclear components. For this project, two HEAs FeCrNiMn and FeCrNiMnAl have been successfully synthesized. Correlated mechanical response has been systematically characterized under a variety of laser processing and ion irradiations. Both high entropy alloys are found to present comparable swelling and extraordinary irradiation tolerance (limited voids and stabilized phase structure under high irradiation dose). In addition, the microstructure and radiation-induced hardening can be tailored by laser processing under additive manufacturing. And we have assembled at LANL a unique database of HEAs containing a total of 674 compositions with Phase Stability information. Based on this, the machine learning and Artificial Intelligence capability now are established to predict the microstructure of casted HEAs by given chemical compositions. This unique integration will lead to an optimal AM recipe for fabricating radiation tolerant HEAs. The development of both modeling models and experimental capability will also benefit other programs at LANL.

  14. High energy proton simulation of 14-MeV neutron damage in Al2O3

    International Nuclear Information System (INIS)

    Muir, D.W.; Bunch, J.M.

    1975-01-01

    High-energy protons are a potentially useful tool for simulating the radiation damage produced by 14-MeV neutrons in CTR materials. A comparison is given of calculations and measurements of the relative damage effectiveness of these two types of radiation in single-crystal Al 2 O 3 . The experiments make use of the prominent absorption band at 206 nm as an index to lattice damage, on the assumption that peak absorption is proportional to the concentration of lattice vacancies. The induced absorption is measured for incident proton energies ranging from 5 to 15 MeV and for 14-MeV neutrons. Recoil-energy spectra are calculated for elastic and inelastic scattering using published angular distributions. Recoil-energy spectra also are calculated for the secondary alpha particles and 12 C nuclei produced by (p,p'α) reactions on 16 O. The recoil spectra are converted to damage-energy spectra and then integrated to yield the damage-energy cross section at each proton energy and for 14 MeV neutrons. A comparison of the calculations with experimental results suggests that damage energy, at least at high energies, is a reasonable criterion for estimating this type of radiation damage. (auth)

  15. Healing of damaged metal by a pulsed high-energy electromagnetic field

    Science.gov (United States)

    Kukudzhanov, K. V.; Levitin, A. L.

    2018-04-01

    The processes of defect (intergranular micro-cracks) transformation are investigated for metal samples in a high-energy short-pulsed electromagnetic field. This investigation is based on a numerical coupled model of the impact of high-energy electromagnetic field on the pre-damaged thermal elastic-plastic material with defects. The model takes into account the melting and evaporation of the metal and the dependence of its physical and mechanical properties on the temperature. The system of equations is solved numerically by finite element method with an adaptive mesh using the arbitrary Euler–Lagrange method. The calculations show that the welding of the crack and the healing of micro-defects under treatment by short pulses of the current takes place. For the macroscopic description of the healing process, the healing and damage parameters of the material are introduced. The healing of micro-cracks improves the material healing parameter and reduces its damage. The micro-crack shapes practically do not affect the time-dependence of the healing and damage under the treatment by the current pulses. These changes are affected only by the value of the initial damage of the material and the initial length of the micro-crack. The time-dependence of the healing and the damage is practically the same for all different shapes of micro-defects, provided that the initial lengths of micro-cracks and the initial damages are the same for these different shapes of defects.

  16. Homogenization-based topology optimization for high-resolution manufacturable micro-structures

    DEFF Research Database (Denmark)

    Groen, Jeroen Peter; Sigmund, Ole

    2018-01-01

    This paper presents a projection method to obtain high-resolution, manufacturable structures from efficient and coarse-scale, homogenization-based topology optimization results. The presented approach bridges coarse and fine scale, such that the complex periodic micro-structures can be represented...... by a smooth and continuous lattice on the fine mesh. A heuristic methodology allows control of the projected topology, such that a minimum length-scale on both solid and void features is ensured in the final result. Numerical examples show excellent behavior of the method, where performances of the projected...

  17. [INVITED] Laser-induced forward transfer: A high resolution additive manufacturing technology

    Science.gov (United States)

    Delaporte, Philippe; Alloncle, Anne-Patricia

    2016-04-01

    Among the additive manufacturing techniques, laser-induced forward transfer addresses the challenges of printing thin films in solid phase or small volume droplets in liquid phase with very high resolution. This paper reviews the physics of this process and explores the pros and cons of this technology versus other digital printing technologies. The main field of applications are printed electronics, organic electronics and tissue engineering, and the most promising short terms ones concern digital laser printing of sensors and conductive tracks. Future directions and emerging areas of interest are discussed such as printing solid from a liquid phase and 3D digital nanomanufacturing.

  18. Determination of pollutants in foundry during the manufacture of metal constructions for high buildings

    Science.gov (United States)

    Ivanova, Irina; Sushko, Elena; Lyshnikova, Anna; Prykina, Larisa

    2018-03-01

    Current developments are devoted to the environmental safety of the foundry. There is a significant amount of pollutants, according to dust, which is released in the working area, during the manufacture of metal structures for high buildings. From the point of dust extraction, the most unfavorable areas are shot blasting, sand-blasting chambers and knockout grills. The weight fraction of dust composition with diameters up to 20 μm reaches 43,8% by mass, according to experimental analysis. This kind of dust is the most dangerous to employees and also it creates problems for dust-cleaning in the air.

  19. Crane RF accelerator for high current radiation damage studies

    International Nuclear Information System (INIS)

    Whitham, K.; Anamkath, H.; Evans, K.; Lyons, S.; Palmer, D.; Miller, R.; Treas, P.; Zante, T.

    1992-01-01

    An electron accelerator was designed and built for the Naval Weapons Support Center for transient radiation effects on electronics experiments and testing. The Crane L Band RF Electron Linac was designed to provide high currents over a wide range of pulse widths and energies. The energy extends to 60 MeV and pulse widths vary from a few ns to 10 μsec. Beam currents range from 20 amps in the short pulse case to 1.5 amps in the long pulse case. This paper describes the linac, its architecture, the e-gun and pulser, waveguides, klystrons and modulator, vacuum system, beam transport, and control systems. fig., tab

  20. Model for visualizing high energy laser (HEL) damage

    Science.gov (United States)

    Erten, Gail

    2017-11-01

    This paper describes and presents results from a model created in MATLAB® to calculate and display the time dependent temperature profile on a target aimpoint as it is being engaged by a high energy laser (HEL) beam. The model uses public domain information namely physics equations of heat conduction and phase changes and material properties such as thermal conductivity/diffusivity, latent heat, specific heat, melting and evaporation points as well as user input material type and thickness. The user also provides time varying characteristics of the HEL beam on the aimpoint, including beam size and intensity distribution (in Watts per centimeter square). The model calculates the temperature distribution at and around the aimpoint and also shows the phase changes of the aimpoint with the material first melting and then evaporating. User programmable features (selecting materials and thickness, erosion rates for melting) make the model highly versatile. The objective is to bridge the divide between remaining faithful to theoretical formulations such as the partial differential equations of heat conduction and at the same time serving practical concerns of the model user who needs to rapidly evaluate HEL thermal effects. One possible use of the tool is to assess lethality values of different aimpoints without costly (as well as often dangerous and destructive) experiments.

  1. Damage thresholds of thin film materials and high reflectors at 248 nm

    International Nuclear Information System (INIS)

    Rainer, F.; Lowdermilk, W.H.; Milam, D.; Carniglia, C.K.; Hart, T.T.; Lichtenstein, T.L.

    1982-01-01

    Twenty-ns, 248-nm KrF laser pulses were used to measure laser damage thresholds for halfwave-thick layers of 15 oxide and fluoride coating materials, and for high reflectance coatings made with 13 combinations of these materials. The damage thresholds of the reflectors and single-layer films were compared to measurements of several properties of the halfwave-thick films to determine whether measurements of these properties of single-layer films to determine whether measurements of these properties of single-layer films were useful for identifying materials for fabrication of damage resistant coatings

  2. A state of the Art report on Manufacturing technology of high burn-up fuel cladding

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyeong Ho; Nam, Cheol; Baek, Jong Hyuk; Choi, Byung Kwon; Park, Sang Yoon; Lee, Myung Ho; Jeong, Yong Hwan

    1999-09-01

    In order to manufacturing the prototype fuel cladding, overall manufacturing processes and technologies should be thoroughly understood on the manufacturing processes and technologies of foreign cladding tubes. Generally, the important technology related to fuel cladding tube manufacturing processes for PWRs/PHWRs is divided into three stages. The first stage is to produce the zirconium sponge from zirconium sand, the second stage is to produce the zircaloy shell or TREX from zirconium sponge ingot and finally, cladding is produced from TREX or zircaloy shell. Therefore, the manufacturing processes including the first and second stages are described in brief in this technology report in order to understand the whole fuel cladding manufacturing processes. (author)

  3. Experimental investigation on high performance RC column with manufactured sand and silica fume

    Science.gov (United States)

    Shanmuga Priya, T.

    2017-11-01

    In recent years, the use High Performance Concrete (HPC) has increased in construction industry. The ingredients of HPC depend on the availability and characteristics of suitable alternative materials. Those alternative materials are silica fume and manufactured sand, a by products from ferro silicon and quarry industries respectively. HPC made with silica fume as partial replacement of cement and manufactured sand as replacement of natural sand is considered as sustainable high performance concrete. In this present study the concrete was designed to get target strength of 60 MPa as per guide lines given by ACI 211- 4R (2008). The laboratory study was carried out experimentally to analyse the axial behavior of reinforced cement HPC column of size 100×100×1000mm and square in cross section. 10% of silica fume was preferred over ordinary portland cement. The natural sand was replaced by 0, 20, 40, 60, 80 and 100% with Manufactured Sand (M-Sand). In this investigation, totally 6 column specimens were cast for mixes M1 to M6 and were tested in 1000kN loading frame at 28 days. From this, Load-Mid height deflection curves were drawn and compared. Maximum ultimate load carrying capacity and the least deflection is obtained for the mix prepared by partial replacement of cement with 10% silica fume & natural sand by 100% M-Sand. The fine, amorphous and pozzalonic nature of silica fume and fine mineral particles in M- Sand increased the stiffness of HPC column. The test results revealed that HPC can be produced by using M-Sand with silica fume.

  4. Early-state damage detection, characterization, and evolution using high-resolution computed tomography

    Science.gov (United States)

    Grandin, Robert John

    Safely using materials in high performance applications requires adequately understanding the mechanisms which control the nucleation and evolution of damage. Most of a material's operational life is spent in a state with noncritical damage, and, for example in metals only a small portion of its life falls within the classical Paris Law regime of crack growth. Developing proper structural health and prognosis models requires understanding the behavior of damage in these early stages within the material's life, and this early-stage damage occurs on length scales at which the material may be considered "granular'' in the sense that the discrete regions which comprise the whole are large enough to require special consideration. Material performance depends upon the characteristics of the granules themselves as well as the interfaces between granules. As a result, properly studying early-stage damage in complex, granular materials requires a means to characterize changes in the granules and interfaces. The granular-scale can range from tenths of microns in ceramics, to single microns in fiber-reinforced composites, to tens of millimeters in concrete. The difficulty of direct-study is often overcome by exhaustive testing of macro-scale damage caused by gross material loads and abuse. Such testing, for example optical or electron microscopy, destructive and further, is costly when used to study the evolution of damage within a material and often limits the study to a few snapshots. New developments in high-resolution computed tomography (HRCT) provide the necessary spatial resolution to directly image the granule length-scale of many materials. Successful application of HRCT with fiber-reinforced composites, however, requires extending the HRCT performance beyond current limits. This dissertation will discuss improvements made in the field of CT reconstruction which enable resolutions to be pushed to the point of being able to image the fiber-scale damage structures and

  5. Spot-shadowing optimization to mitigate damage growth in a high-energy-laser amplifier chain.

    Science.gov (United States)

    Bahk, Seung-Whan; Zuegel, Jonathan D; Fienup, James R; Widmayer, C Clay; Heebner, John

    2008-12-10

    A spot-shadowing technique to mitigate damage growth in a high-energy laser is studied. Its goal is to minimize the energy loss and undesirable hot spots in intermediate planes of the laser. A nonlinear optimization algorithm solves for the complex fields required to mitigate damage growth in the National Ignition Facility amplifier chain. The method is generally applicable to any large fusion laser.

  6. High dose neutron irradiation damage in beryllium as blanket material

    Energy Technology Data Exchange (ETDEWEB)

    Chakin, V.P. E-mail: fae@niiar.ru; Kazakov, V.A.; Teykovtsev, A.A.; Pimenov, V.V.; Shimansky, G.A.; Ostrovsky, Z.E.; Suslov, D.N.; Latypov, R.N.; Belozerov, S.V.; Kupriyanov, I.B. E-mail: vniinm.400@g23.relkom.ru

    2001-11-01

    The paper presents the investigation results of beryllium products that operated in the SM and BOR-60 reactors up to neutron doses of 2.8x10{sup 22} and 8.0x10{sup 22} cm{sup -2} (E>1 MeV), respectively. The calculated and experimental data are given on helium and tritium accumulation, swelling, micro-hardness and thermal conductivity. The microstructural investigation results of irradiated beryllium are also presented. It is shown that the rate of helium and tritium accumulation in beryllium in the SM and BOR-60 reactors is high enough, which is of interest from the viewpoint of modeling the working conditions of the DEMO fusion reactor. Swelling of beryllium at irradiation temperature of 70-150 deg. C and neutron fluence of 2.8x10{sup 22} cm{sup -2} (E>1 MeV) makes up 0.8-1.5%, at 400 deg. C and fluence of 8x10{sup 22} cm{sup -2} (E>1 MeV)-3.2-5.0%. Irradiation hardening and decrease of thermal conductivity strongly depend on the irradiation temperature and are more significant at reduced temperatures. All results presented in the paper were analyzed with due account of the supposed working parameters of the DEMO fusion reactor blanket.

  7. High dose neutron irradiation damage in beryllium as blanket material

    International Nuclear Information System (INIS)

    Chakin, V.P.; Kazakov, V.A.; Teykovtsev, A.A.; Pimenov, V.V.; Shimansky, G.A.; Ostrovsky, Z.E.; Suslov, D.N.; Latypov, R.N.; Belozerov, S.V.; Kupriyanov, I.B.

    2001-01-01

    The paper presents the investigation results of beryllium products that operated in the SM and BOR-60 reactors up to neutron doses of 2.8x10 22 and 8.0x10 22 cm -2 (E>1 MeV), respectively. The calculated and experimental data are given on helium and tritium accumulation, swelling, micro-hardness and thermal conductivity. The microstructural investigation results of irradiated beryllium are also presented. It is shown that the rate of helium and tritium accumulation in beryllium in the SM and BOR-60 reactors is high enough, which is of interest from the viewpoint of modeling the working conditions of the DEMO fusion reactor. Swelling of beryllium at irradiation temperature of 70-150 deg. C and neutron fluence of 2.8x10 22 cm -2 (E>1 MeV) makes up 0.8-1.5%, at 400 deg. C and fluence of 8x10 22 cm -2 (E>1 MeV)-3.2-5.0%. Irradiation hardening and decrease of thermal conductivity strongly depend on the irradiation temperature and are more significant at reduced temperatures. All results presented in the paper were analyzed with due account of the supposed working parameters of the DEMO fusion reactor blanket

  8. Net Shape Manufacturing of Accelerator Components by High Pressure Combustion Driven Powder Compaction

    CERN Document Server

    Nagarathnam, Karthik

    2005-01-01

    We present an overview of the net shape and cost-effective manufacturing aspects of high density accelerator (normal and superconducting) components (e.g., NLC Copper disks) and materials behavior of copper, stainless steel, refractory materials (W, Mo and TZM), niobium and SiC by innovative high pressure Combustion Driven Compaction (CDC) technology. Some of the unique process advantages include high densities, net-shaping, improved surface finish/quality, suitability for simple/complex geometries, synthesis of single as well as multilayered materials, milliseconds of compaction process time, little or no post-machining, and process flexibility. Some of the key results of CDC fabricated sample geometries, process optimization, sintering responses and structure/property characteristics such as physical properties, surface roughness/quality, electrical conductivity, select microstructures and mechanical properties will be presented. Anticipated applications of CDC compaction include advanced x-ray targets, vac...

  9. Aging, Loss-of-Coolant Accident (LOCA), and high potential testing of damaged cables

    International Nuclear Information System (INIS)

    Vigil, R.A.; Jacobus, M.J.

    1994-04-01

    Experiments were conducted to assess the effects of high potential testing of cables and to assess the survivability of aged and damaged cables under Loss-of-Coolant Accident (LOCA) conditions. High potential testing at 240 Vdc/mil on undamaged cables suggested that no damage was incurred on the selected virgin cables. During aging and LOCA testing, Okonite ethylene propylene rubber (EPR) cables with a bonded jacket experienced unexpected failures. The failures appear to be primarily related to the level of thermal aging and the presence of a bonded jacket that ages more rapidly than the insulation. For Brand Rex crosslinked polyolefin (XLPO) cables, the results suggest that 7 mils of insulation remaining should give the cables a high probability of surviving accident exposure following aging. The voltage necessary to detect when 7 mils of insulation remain on unaged Brand Rex cables is approximately 35 kVdc. This voltage level would almost certainly be unacceptable to a utility for use as a damage assessment tool. However, additional tests indicated that a 35 kvdc voltage application would not damage virgin Brand Rex cables when tested in water. Although two damaged Rockbestos silicone rubber cables also failed during the accident test, no correlation between failures and level of damage was apparent

  10. Additive manufacturing of a high niobium-containing titanium aluminide alloy by selective electron beam melting

    International Nuclear Information System (INIS)

    Tang, H.P.; Yang, G.Y.; Jia, W.P.; He, W.W.; Lu, S.L.; Qian, M.

    2015-01-01

    Additive manufacturing (AM) offers a radical net-shape manufacturing approach for titanium aluminide alloys but significant challenges still remain. A study has been made of the AM of a high niobium-containing titanium aluminide alloy (Ti–45Al–7Nb–0.3W, in at% throughout the paper) using selective electron beam melting (SEBM). The formation of various types of microstructural defects, including banded structures caused by the vaporization of aluminum, was investigated with respect to different processing parameters. To avoid both micro- and macro-cracks, the use of higher preheating temperatures and an intermediate reheating process (to reheat each solidified layer during SEBM) was assessed in detail. These measures enabled effective release of the thermal stress that developed during SEBM and therefore the avoidance of cracks. In addition, the processing conditions for the production of a fine full lamellar microstructure were identified. As a result, the Ti–45Al–7Nb–0.3W alloy fabricated showed outstanding properties (compression strength: 2750 MPa; strain-to-fracture: 37%). SEBM can be used to fabricate high performance titanium aluminide alloys with appropriate processing parameters and pathways

  11. Additive manufacturing of a high niobium-containing titanium aluminide alloy by selective electron beam melting

    Energy Technology Data Exchange (ETDEWEB)

    Tang, H.P., E-mail: thpfys@126.com [State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi' an 710016 (China); Yang, G.Y.; Jia, W.P.; He, W.W.; Lu, S.L. [State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi' an 710016 (China); Qian, M., E-mail: ma.qian@rmit.edu.au [State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi' an 710016 (China); RMIT University, School of Aerospace, Mechanical and Manufacturing Engineering, Centre for Additive Manufacturing, Melbourne, VIC 3001 (Australia)

    2015-06-11

    Additive manufacturing (AM) offers a radical net-shape manufacturing approach for titanium aluminide alloys but significant challenges still remain. A study has been made of the AM of a high niobium-containing titanium aluminide alloy (Ti–45Al–7Nb–0.3W, in at% throughout the paper) using selective electron beam melting (SEBM). The formation of various types of microstructural defects, including banded structures caused by the vaporization of aluminum, was investigated with respect to different processing parameters. To avoid both micro- and macro-cracks, the use of higher preheating temperatures and an intermediate reheating process (to reheat each solidified layer during SEBM) was assessed in detail. These measures enabled effective release of the thermal stress that developed during SEBM and therefore the avoidance of cracks. In addition, the processing conditions for the production of a fine full lamellar microstructure were identified. As a result, the Ti–45Al–7Nb–0.3W alloy fabricated showed outstanding properties (compression strength: 2750 MPa; strain-to-fracture: 37%). SEBM can be used to fabricate high performance titanium aluminide alloys with appropriate processing parameters and pathways.

  12. Operation of microstrip gas chambers manufactured on glass coated with high resistivity diamond-like layers

    CERN Document Server

    Boimska, B; Dominik, Wojciech; Hoch, M; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1997-01-01

    We describe recent observations and measurements realized with micro-strip gas chambers (MSGCs) manufactured on boro-silicate glass coated with a thin layer of diamond-like carbon (DLC) having a surface resistivity around 4.10$^{16}\\Omega/\\Box$. The role of the back-pla electrode configuration and potential in the detector performance has been studied. Even for this very high resistivity of the coatings, MSGCs operate differently from those manufactured on bare boro-silicate glass; the charge gain increases with the radiation flux for counting rates above 103 Hz/mm2, reaching a value 60% higher for 105 Hz/mm2. This behavior does not depend on the presence and potential of the back plane electrode; however, both maximum gain and rate capability are influenced by the drift field. From this study, compared with measurements realized previously with other detectors, we deduce that for stable high rate operation of MSGCs the resistivity of the coating should not exceed ~10$^{15}\\Omega/\\Box$.

  13. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets

    NARCIS (Netherlands)

    Li, L; Tirado, A.; Nlebedim, I.C.; Rios, O.; Post, B.; Kunc, V.; Lowden, R.R.; Lara-Curzio, E.; Fredette, R.; Ormerod, J.; Lograsso, T.A.; Paranthaman, M.P.

    2016-01-01

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing

  14. Study on Relaxation Damage Properties of High Viscosity Asphalt Sand under Uniaxial Compression

    Directory of Open Access Journals (Sweden)

    Yazhen Sun

    2018-01-01

    Full Text Available Laboratory investigations of relaxation damage properties of high viscosity asphalt sand (HVAS by uniaxial compression tests and modified generalized Maxwell model (GMM to simulate viscoelastic characteristics coupling damage were carried out. A series of uniaxial compression relaxation tests were performed on HVAS specimens at different temperatures, loading rates, and constant levels of input strain. The results of the tests show that the peak point of relaxation modulus is highly influenced by the loading rate in the first half of an L-shaped curve, while the relaxation modulus is almost constant in the second half of the curve. It is suggested that for the HVAS relaxation tests, the temperature should be no less than −15°C. The GMM is used to determine the viscoelastic responses, the Weibull distribution function is used to characterize the damage of the HVAS and its evolution, and the modified GMM is a coupling of the two models. In this paper, the modified GMM is implemented through a secondary development with the USDFLD subroutine to analyze the relaxation damage process and improve the linear viscoelastic model in ABAQUS. Results show that the numerical method of coupling damage provides a better approximation of the test curve over almost the whole range. The results also show that the USDFLD subroutine can effectively predict the relaxation damage process of HVAS and can provide a theoretical support for crack control of asphalt pavements.

  15. Precision ring rolling technique and application in high-performance bearing manufacturing

    Directory of Open Access Journals (Sweden)

    Hua Lin

    2015-01-01

    Full Text Available High-performance bearing has significant application in many important industry fields, like automobile, precision machine tool, wind power, etc. Precision ring rolling is an advanced rotary forming technique to manufacture high-performance seamless bearing ring thus can improve the working life of bearing. In this paper, three kinds of precision ring rolling techniques adapt to different dimensional ranges of bearings are introduced, which are cold ring rolling for small-scale bearing, hot radial ring rolling for medium-scale bearing and hot radial-axial ring rolling for large-scale bearing. The forming principles, technological features and forming equipments for three kinds of precision ring rolling techniques are summarized, the technological development and industrial application in China are introduced, and the main technological development trend is described.

  16. A prediction and damage assessment model for snowmelt flood events in middle and high latitudes Region

    Science.gov (United States)

    Qiao, C.; Huang, Q.; Chen, T.; Zhang, X.

    2017-12-01

    In the context of global warming, the snowmelt flood events in the mountainous area of the middle and high latitudes are increasingly frequent and create severe casualties and property damages. Carrying out the prediction and risk assessment of the snowmelt flood is of great importance in the water resources management, the flood warning and prevention. Based on the remote sensing and GIS techniques, the relationships of the variables influencing the snowmelt flood such as the snow area, the snow depth, the air temperature, the precipitation, the land topography and land covers are analyzed and a prediction and damage assessment model for snowmelt floods is developed. This model analyzes and predicts the flood submerging area, flood depth, flood grade, and the damages of different underlying surfaces in the study area in a given time period based on the estimation of snowmelt amount, the snowmelt runoff, the direction and velocity of the flood. Then it was used to predict a snowmelt flood event in the Ertis River Basin in northern Xinjiang, China, during March and June, 2005 and to assess its damages including the damages of roads, transmission lines, settlements caused by the floods and the possible landslides using the hydrological and meteorological data, snow parameter data, DEM data and land use data. A comparison was made between the prediction results from this model and observation data including the flood measurement and its disaster loss data, which suggests that this model performs well in predicting the strength and impact area of snowmelt flood and its damage assessment. This model will be helpful for the prediction and damage assessment of snowmelt flood events in the mountainous area in the middle and high latitudes in spring, which has great social and economic significance because it provides a relatively reliable method for snowmelt flood prediction and reduces the possible damages caused by snowmelt floods.

  17. Particle damage sources for fused silica optics and their mitigation on high energy laser systems.

    Science.gov (United States)

    Bude, J; Carr, C W; Miller, P E; Parham, T; Whitman, P; Monticelli, M; Raman, R; Cross, D; Welday, B; Ravizza, F; Suratwala, T; Davis, J; Fischer, M; Hawley, R; Lee, H; Matthews, M; Norton, M; Nostrand, M; VanBlarcom, D; Sommer, S

    2017-05-15

    High energy laser systems are ultimately limited by laser-induced damage to their critical components. This is especially true of damage to critical fused silica optics, which grows rapidly upon exposure to additional laser pulses. Much progress has been made in eliminating damage precursors in as-processed fused silica optics (the advanced mitigation process, AMP3), and very high damage resistance has been demonstrated in laboratory studies. However, the full potential of these improvements has not yet been realized in actual laser systems. In this work, we explore the importance of additional damage sources-in particular, particle contamination-for fused silica optics fielded in a high-performance laser environment, the National Ignition Facility (NIF) laser system. We demonstrate that the most dangerous sources of particle contamination in a system-level environment are laser-driven particle sources. In the specific case of the NIF laser, we have identified the two important particle sources which account for nearly all the damage observed on AMP3 optics during full laser operation and present mitigations for these particle sources. Finally, with the elimination of these laser-driven particle sources, we demonstrate essentially damage free operation of AMP3 fused silica for ten large optics (a total of 12,000 cm 2 of beam area) for shots from 8.6 J/cm 2 to 9.5 J/cm 2 of 351 nm light (3 ns Gaussian pulse shapes). Potentially many other pulsed high energy laser systems have similar particle sources, and given the insight provided by this study, their identification and elimination should be possible. The mitigations demonstrated here are currently being employed for all large UV silica optics on the National Ignition Facility.

  18. Oxidative DNA damage and repair in skeletal muscle of humans exposed to high-altitude hypoxia

    DEFF Research Database (Denmark)

    Lundby, Carsten; Pilegaard, Henriette; van Hall, Gerrit

    2003-01-01

    Recent research suggests that high-altitude hypoxia may serve as a model for prolonged oxidative stress in healthy humans. In this study, we investigated the consequences of prolonged high-altitude hypoxia on the basal level of oxidative damage to nuclear DNA in muscle cells, a major oxygen-consuming...

  19. Improvements in quality of as-manufactured fuels for high-temperature gas-cooled reactors

    International Nuclear Information System (INIS)

    Minato, Kazuo; Kikuchi, Hironobu; Tobita, Tsutomu; Fukuda, Kousaku; Kaneko, Mitsunobu; Suzuki, Nobuyuki; Yoshimuta, Shigeharu; Tomimoto, Hiroshi.

    1997-01-01

    The mechanisms of coating failure of the fuel particles for the high-temperature gas-cooled reactors during coating and compaction processes of the fuel fabrication were studied to determine a way to reduce the defective particle fraction of the as-manufactured fuels. Through the observation of the defective particles, it was found that the coating failure during the coating process was mainly caused by the strong mechanical shocks to the particles given by violent particle fluidization in the coater and by unloading and loading of the particles. The coating failure during the compaction process was probably related to the direct contact with neighboring particles in the fuel compacts. The coating process was improved by optimizing the mode of the particle fluidization and by developing the process without unloading and loading of the particles at intermediate coating process. The compaction process was improved by optimizing the combination of the pressing temperature and the pressing speed of the overcoated particles. Through these modifications of the fabrication process, the quality of the as-manufactured fuel compacts was improved outstandingly. (author)

  20. Filter effectiveness in the manufacture of high-chromium steel castings

    Directory of Open Access Journals (Sweden)

    M. Garbiak

    2011-01-01

    Full Text Available The paper presents the results of studies on the application of ceramic filters in the manufacture of cast hearth plates at the WestPomeranian University of Technology in Szczecin. Castings were poured from the heat-resistant G-X40CrNiSi27-4 cast steel in greensand moulds. The development of casting manufacturing technology included the following studies: analysis of the causes of nonmetallicinclusions in high-chromium alloys, computer simulation of mould filling with liquid metal using standard gating systems without filters and new systems with the built-in filter, making pilot castings, quantitative determination of the content of non-metallicinclusions, determination of the oxygen and nitrogen content, and evaluation of the extent of occurrence of the raw casting s urfacedefects. As a result of the conducted studies and analyses, the quality of produced castings was improved, mainly through the reducedcontent of non-metallic inclusions and better raw casting surface quality.

  1. Execution techniques for high level radioactive waste disposal. 4. Design and manufacturing procedure of engineered barriers

    International Nuclear Information System (INIS)

    Ogata, Nobuhide; Kosaki, Akio; Ueda, Hiroyoshi; Asano, Hidekazu; Takao, Hajime

    1999-01-01

    Ensuring the physical integrity of engineered barriers for an extremely long time period is necessary for geological disposal of high-level radioactive wastes. This report describes the design process and the designed configurations of both overpack and buffer as engineered barriers. Manufacturing procedure, quality control and inspection methods are also summarized. Carbon steel was selected as a structural material of the overpack and the specification of the overpack was determined assuming disposal in the depths of 1000 m below surface of crystalline rock site. The mixture of bentonite and sand (80% sodium bentonite and 20% silica sand by mass) was selected as material for a buffer from mainly its permeability and characteristics of self-sealing of a gap occurred in construction work. Welding method of a lid onto the main body of the overpack, uniting method of a corrosion-resistance layer and the structural component in the case of a composite overpack and manufacturing procedures of both blocks-type and monolithic-type buffers are also investigated. (author)

  2. Fully printed and integrated electrolyzer cells with additive manufacturing for high-efficiency water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye; Dohrmann, Yeshi; List, Frederick A.; Green, Johney B.; Babu, Sudarsanam S.; Zhang, Feng-Yuan

    2018-04-01

    Using additive manufacturing (AM) technology, a fundamental material and structure innovation was proposed to significantly increase the energy efficiency, and to reduce the weight, volume and component quantity of proton exchange membrane electrolyzer cells (PEMECs). Four conventional parts (liquid/gas diffusion layer, bipolar plate, gasket, and current distributor) in a PEMEC were integrated into one multifunctional AM plate without committing to tools or molds for the first time. In addition, since the interfacial contact resistances between those parts were eliminated, the comprehensive in-situ characterizations of AM cells showed that an excellent energy efficiency of up to 86.48% was achieved at 2 A/cm2 and 80 degrees C, and the hydrogen generation rate was increased by 61.81% compared to the conventional cell. More importantly, the highly complex inner structures of the AM integrated multifunctional plates also exhibit the potential to break limitations of conventional manufacture methods for hydrogen generation and to open a door for the development of other energy conversion devices, including fuel cells, solar cells and batteries.

  3. Development of an Improved Process for Installation Projects of High Technology Manufacturing Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Quintana, Sarah V. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-04-30

    High technology manufacturing equipment is utilized at Los Alamos National Laboratory (LANL) to support nuclear missions. This is undertaken from concept initiation where equipment is designed and then taken through several review phases, working closely with system engineers (SEs) responsible for each of the affected systems or involved disciplines (from gasses to HVAC to structural, etc.). After the design is finalized it moves to procurement and custom fabrication of the equipment and equipment installation, including all of the paperwork involved. Not only are the engineering and manufacturing aspects important, but also the scheduling, financial forecasting, and planning portions that take place initially and are sometimes modified as the project progresses should requirements, changes or additions become necessary. The process required to complete a project of this type, including equipment installation, is unique and involves numerous steps to complete. These processes can be improved and recent work on the Direct Current Arc (DC Arc) Glovebox Design, Fabrication and Installation Project provides an opportunity to identify some important lessons learned (LL) that can be implemented in the future for continued project improvement and success.

  4. High Resolution SAR Imaging Employing Geometric Features for Extracting Seismic Damage of Buildings

    Science.gov (United States)

    Cui, L. P.; Wang, X. P.; Dou, A. X.; Ding, X.

    2018-04-01

    Synthetic Aperture Radar (SAR) image is relatively easy to acquire but difficult for interpretation. This paper probes how to identify seismic damage of building using geometric features of SAR. The SAR imaging geometric features of buildings, such as the high intensity layover, bright line induced by double bounce backscattering and dark shadow is analysed, and show obvious differences texture features of homogeneity, similarity and entropy in combinatorial imaging geometric regions between the un-collapsed and collapsed buildings in airborne SAR images acquired in Yushu city damaged by 2010 Ms7.1 Yushu, Qinghai, China earthquake, which implicates a potential capability to discriminate collapsed and un-collapsed buildings from SAR image. Study also shows that the proportion of highlight (layover & bright line) area (HA) is related to the seismic damage degree, thus a SAR image damage index (SARDI), which related to the ratio of HA to the building occupation are of building in a street block (SA), is proposed. While HA is identified through feature extraction with high-pass and low-pass filtering of SAR image in frequency domain. A partial region with 58 natural street blocks in the Yushu City are selected as study area. Then according to the above method, HA is extracted, SARDI is then calculated and further classified into 3 classes. The results show effective through validation check with seismic damage classes interpreted artificially from post-earthquake airborne high resolution optical image, which shows total classification accuracy 89.3 %, Kappa coefficient 0.79 and identical to the practical seismic damage distribution. The results are also compared and discussed with the building damage identified from SAR image available by other authors.

  5. Low cycle fatigue: high cycle fatigue damage accumulation in a 304L austenitic stainless steel

    International Nuclear Information System (INIS)

    Lehericy, Y.

    2007-05-01

    The aim of this study was to evaluate the consequences of a Low Cycle Fatigue pre-damage on the subsequent fatigue limit of a 304L stainless steel. The effects of hardening and severe roughness (grinding) have also been investigated. In a first set of tests, the evolution of the surface damage induced by the different LCF pre-cycling was characterized. This has permitted to identify mechanisms and kinetics of damage in the plastic domain for different surface conditions. Then, pre-damaged samples were tested in the High Cycle Fatigue domain in order to establish the fatigue limits associated with each level of pre-damage. Results evidence that, in the case of polished samples, an important number of cycles is required to initiate surface cracks ant then to affect the fatigue limit of the material but, in the case of ground samples, a few number of cycles is sufficient to initiate cracks and to critically decrease the fatigue limit. The fatigue limit of pre-damaged samples can be estimated using the stress intensity factor threshold. Moreover, this detrimental effect of severe surface conditions is enhanced when fatigue tests are performed under a positive mean stress (author)

  6. Increased effects of machining damage in beryllium observed at high strain rates

    International Nuclear Information System (INIS)

    Beitscher, S.; Brewer, A.W.; Corle, R.R.

    1980-01-01

    Tensile tests at both low and high strain rates, and also impact shear tests, were performed on a weldable grade powder-source beryllium. Impact energies increased by a factor of 2 to 3 from the as-machined level after etching or annealing. Similar increases in the ductility from machining damage removal were observed from the tensile data at the higher strain rate (10 s -1 ) while an insignificant increase in elongation was measured at the lower strain rate (10 -4 s -1 ). High strain-rate tests appear to be more sensitive and reliable for evaluating machining practice and damage removal methods for beryllium components subjected to sudden loads. 2 tables

  7. A survey of high explosive-induced damage and spall in selected metals using proton radiography

    International Nuclear Information System (INIS)

    Holtkamp, D.B.; Clark, D.A.; Ferm, E.N.; Gallegos, R.A.; Hammon, D.; Hemsing, W.F.; Hogan, G.E.; Holmes, V.H.; King, N.S.P.; Lopez, R.P.; Merrill, F.E.; Morris, C.L.; Morley, K.B.; Murray, M.M.; Pazuchanics, P.D.; Prestridge, K.P.; Quintana, J.P.; Saunders, A.; Shinas, M.A.; Stacy, H.L.

    2004-01-01

    Multiple spall and damage layers can be created in metal when the free surface reflects a Taylor wave generated by high explosives. These phenomena have been explored in different thicknesses of several metals (tantalum, copper, 6061 T6-aluminum, and tin) using high-energy proton radiography. Multiple images (up to 21) can be produced of the dynamic evolution of damaged material on the microsecond time scale with a <50 ns 'shutter' time. Movies and multiframe still images of areal and (Abel inverted) volume densities are presented. An example of material that is likely melted on release (tin) is also presented

  8. High dose radiation damage in nuclear energy structural materials investigated by heavy ion irradiation simulation

    International Nuclear Information System (INIS)

    Zheng Yongnan; Xu Yongjun; Yuan Daqing

    2014-01-01

    Structural materials in ITER, ADS and fast reactor suffer high dose irradiations of neutrons and/or protons, that leads to severe displacement damage up to lOO dpa per year. Investigation of radiation damage induced by such a high dose irradiation has attracted great attention along with the development of nuclear energy facilities of new generation. However, it is deeply hampered for the lacking of high dose neutron and proton sources. Irradiation simulation of heavy ions produced by accelerators opens up an effective way for laboratory investigation of high dose irradiation induced radiation damage encountered in the ITER, ADS, etc. Radiation damage is caused mainly by atomic displacement in materials. The displacement rate of heavy ions is about lO 3 ∼10 7 orders higher than those of neutrons and protons. High displacement rate of heavy ions significantly reduces the irradiation time. The heavy ion irradiation simulation technique (HIIS) technique has been developed at China Institute of Atomic Energy and a series of the HIIS experiments have been performed to investigate radiation damage in stainless steels, tungsten and tantalum at irradiation temperatures from room temperature to 800 ℃ and in the irradiation dose region up to 100 dpa. The experimental results show that he radiation swelling peak for the modified stainless steel appears in the temperature region around 580 ℃ and the radiation damage is more sensitive to the temperature, the size of the radiation induced vacancy cluster or void increase with the increasing of the irradiation dose, and among the three materials the home-made modified stainless steel has the best radiation resistant property. (authors)

  9. Additive Manufacturing and High-Performance Computing: a Disruptive Latent Technology

    Science.gov (United States)

    Goodwin, Bruce

    2015-03-01

    This presentation will discuss the relationship between recent advances in Additive Manufacturing (AM) technology, High-Performance Computing (HPC) simulation and design capabilities, and related advances in Uncertainty Quantification (UQ), and then examines their impacts upon national and international security. The presentation surveys how AM accelerates the fabrication process, while HPC combined with UQ provides a fast track for the engineering design cycle. The combination of AM and HPC/UQ almost eliminates the engineering design and prototype iterative cycle, thereby dramatically reducing cost of production and time-to-market. These methods thereby present significant benefits for US national interests, both civilian and military, in an age of austerity. Finally, considering cyber security issues and the advent of the ``cloud,'' these disruptive, currently latent technologies may well enable proliferation and so challenge both nuclear and non-nuclear aspects of international security.

  10. Additive Manufacturing of NiTiHf High Temperature Shape Memory Alloy

    Science.gov (United States)

    Benafan, Othmane; Bigelow, Glen S.; Elahinia, Mohammad; Moghaddam, Narges Shayesteh; Amerinatanzi, Amirhesam; Saedi, Soheil; Toker, Guher Pelin; Karaca, Haluk

    2017-01-01

    Additive manufacturing of a NiTi-20Hf high temperature shape memory alloy (HTSMA) was investigated. A selective laser melting (SLM) process by Phenix3D Systems was used to develop components from NiTiHf powder (of approximately 25-75 m particle fractions), and the thermomechanical response was compared to the conventionally vacuum induction skull melted counterpart. Transformation temperatures of the SLM material were found to be slightly lower due to the additional oxygen pick up from the gas atomization and melting process. The shape memory response in compression was measured for stresses up to 500 MPa, and transformation strains were found to be very comparable (Up to 1.26 for the as-extruded; up to 1.52 for SLM).

  11. Northwest Energy Efficient Manufactured Housing Program High-Performance Test Homes

    Energy Technology Data Exchange (ETDEWEB)

    Hewes, Tom; Peeks, Brady

    2015-09-15

    ?This project represents the third phase of a multi-year effort to develop and bring to market a High Performance Manufactured Home (HPMH). The scope of this project involved building four HPMH prototypes, resulting in what is expected to be a 30% savings relative to the Building America Benchmark. (The actual % savings varies depending on choice of heating equipment and climate zone). The HPMH home is intended to make significant progress toward performing as zero-net-energy ready. Previous phases of this project created a HPMH specification and prototyped individual measures from the package to obtain engineering approvals and develop preliminary factory construction processes. This report describes the project team's work during 2014 to build prototype homes to the HPMH specifications and to monitor the homes for energy performance and durability during 2014. Monitoring is expected to continue into 2016.

  12. Northwest Energy Efficient Manufactured Housing Program High-Performance Test Homes

    Energy Technology Data Exchange (ETDEWEB)

    Hewes, Tom [Building America Partnership for Improved Residential Construction, Corvallis, OR (United States); Peeks, Brady [Building America Partnership for Improved Residential Construction, Corvallis, OR (United States)

    2015-09-01

    This project represents the third phase of a multi-year effort to develop and bring to market a High Performance Manufactured Home (HPMH), which is intended to make significant progress toward performing as zero-net-energy ready. The scope of this project involved building four HPMH prototypes, resulting in what is expected to be a 30% savings relative to the Building America Benchmark. (The actual percent savings varies depending on choice of heating equipment and climate zone). Previous phases of this project created a HPMH specification and prototyped individual measures from the package to obtain engineering approvals and develop preliminary factory construction processes. This report describes the project team's work during 2014 to build prototype homes to the HPMH specifications and to monitor the homes for energy performance and durability during 2014. Monitoring is expected to continue into 2016.

  13. Manufacturing polymer light emitting diode with high luminance efficiency by solution process

    Science.gov (United States)

    Kim, Miyoung; Jo, SongJin; Yang, Ho Chang; Yoon, Dang Mo; Kwon, Jae-Taek; Lee, Seung-Hyun; Choi, Ju Hwan; Lee, Bum-Joo; Shin, Jin-Koog

    2012-06-01

    While investigating polymer light emitting diodes (polymer-LEDs) fabricated by solution process, surface roughness influences electro-optical (E-O) characteristics. We expect that E-O characteristics such as luminance and power efficiency related to surface roughness and layer thickness of emitting layer with poly-9-Vinylcarbazole. In this study, we fabricated polymer organic light emitting diodes by solution process which guarantees easy, eco-friendly and low cost manufacturing for flexible display applications. In order to obtain high luminescence efficiency, E-O characteristics of these devices by varying parameters for printing process have been investigated. Therefore, we optimized process condition for polymer-LEDs by adjusting annealing temperatures of emission, thickness of emission layer showing efficiency (10.8 cd/A) at 10 mA/cm2. We also checked wavelength dependent electroluminescence spectrum in order to find the correlation between the variation of efficiency and the thickness of the layer.

  14. Micro Manufacturing

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard

    2003-01-01

    Manufacturing deals with systems that include products, processes, materials and production systems. These systems have functional requirements, constraints, design parameters and process variables. They must be decomposed in a systematic manner to achieve the best possible system performance....... If a micro manufacturing system isn’t designed rationally and correctly, it will be high-cost, unreliable, and not robust. For micro products and systems it is a continuously increasing challenge to create the operational basis for an industrial production. As the products through product development...... processes are made applicable to a large number of customers, the pressure in regard to developing production technologies that make it possible to produce the products at a reasonable price and in large numbers is growing. The micro/nano manufacturing programme at the Department of Manufacturing...

  15. Proton-irradiation technology for high-frequency high-current silicon welding diode manufacturing

    International Nuclear Information System (INIS)

    Lagov, P B; Drenin, A S; Zinoviev, M A

    2017-01-01

    Different proton irradiation regimes were tested to provide more than 20 kHz-frequency, soft reverse recovery “snap-less” behavior, low forward voltage drop and leakage current for 50 mm diameter 7 kA/400 V welding diode Al/Si/Mo structure. Silicon diode with such parameters is very suitable for high frequency resistance welding machines of new generation for robotic welding. (paper)

  16. Proton-irradiation technology for high-frequency high-current silicon welding diode manufacturing

    Science.gov (United States)

    Lagov, P. B.; Drenin, A. S.; Zinoviev, M. A.

    2017-05-01

    Different proton irradiation regimes were tested to provide more than 20 kHz-frequency, soft reverse recovery “snap-less” behavior, low forward voltage drop and leakage current for 50 mm diameter 7 kA/400 V welding diode Al/Si/Mo structure. Silicon diode with such parameters is very suitable for high frequency resistance welding machines of new generation for robotic welding.

  17. High-energy-neutron damage in Nb3Sn: changes in critical properties, and damage-energy analysis

    International Nuclear Information System (INIS)

    Snead, C.L. Jr.; Parkin, D.M.; Guinan, M.W.

    1981-01-01

    Filamentary wires of Nb 3 Sn have been irradiated with fission-reactor, 14.8-MeV, and d-Be neutrons and the changes in critical properties measured. The changes observed scale reasonably well with the calculated damage energies for the irradiations. A critical dose for operation of these conductors in fusion-magnet applications is determined to be 0.19 eV/atom damage energy or 0.0019 dpa

  18. Automated High-Volume Manufacturing of Modular Photovoltaic Panel Assemblies for Space Solar Arrays, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Deployable Space Systems, Inc. (DSS) will focus the proposed SBIR program on the creation and development of an automated robotic manufacturing infrastructure...

  19. Multiple High-Fidelity Modeling Tools for Metal Additive Manufacturing Process Development, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Despite the rapid commercialization of additive manufacturing technology such as selective laser melting, SLM, there are gaps in process modeling and material...

  20. Multiple High-Fidelity Modeling Tools for Metal Additive Manufacturing Process Development, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Despite the rapid commercialization of additive manufacturing technology such as selective laser melting, SLM, there are gaps in process modeling and material...

  1. Rapid Manufacture of Combustion Chambers Using Ductile, High Strength MMCs (1000-803), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Triton Systems, Inc. (Triton) proposes to develop a cost-effective manufacturing approach to fabricate combustion chambers for a rocket technology demonstrator...

  2. A comprehensive analysis of earthquake damage patterns using high dimensional model representation feature selection

    Science.gov (United States)

    Taşkin Kaya, Gülşen

    2013-10-01

    Recently, earthquake damage assessment using satellite images has been a very popular ongoing research direction. Especially with the availability of very high resolution (VHR) satellite images, a quite detailed damage map based on building scale has been produced, and various studies have also been conducted in the literature. As the spatial resolution of satellite images increases, distinguishability of damage patterns becomes more cruel especially in case of using only the spectral information during classification. In order to overcome this difficulty, textural information needs to be involved to the classification to improve the visual quality and reliability of damage map. There are many kinds of textural information which can be derived from VHR satellite images depending on the algorithm used. However, extraction of textural information and evaluation of them have been generally a time consuming process especially for the large areas affected from the earthquake due to the size of VHR image. Therefore, in order to provide a quick damage map, the most useful features describing damage patterns needs to be known in advance as well as the redundant features. In this study, a very high resolution satellite image after Iran, Bam earthquake was used to identify the earthquake damage. Not only the spectral information, textural information was also used during the classification. For textural information, second order Haralick features were extracted from the panchromatic image for the area of interest using gray level co-occurrence matrix with different size of windows and directions. In addition to using spatial features in classification, the most useful features representing the damage characteristic were selected with a novel feature selection method based on high dimensional model representation (HDMR) giving sensitivity of each feature during classification. The method called HDMR was recently proposed as an efficient tool to capture the input

  3. Prediction of microstructure and ductile damage of a high-speed railway axle steel during cross wedge rolling

    OpenAIRE

    Huo, Y; Lin, J; Bai, Q; Wang, B; Tang, X; Ji, H

    2016-01-01

    Microstructure and ductile damage have a significant influence on the deformation behavior of high-speed railway axles during hot cross wedge rolling (CWR) and its final performance. In this study, based on the continuum damage mechanics, a multiaxial constitutive model coupling microstructure and ductile damage was established to predict the evolution of microstructure and ductile damage of 25CrMo4 during hot CWR processes. Material constants within the multiaxial constitutive model were det...

  4. Solion ion source for high-efficiency, high-throughput solar cell manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Koo, John, E-mail: john-koo@amat.com; Binns, Brant; Miller, Timothy; Krause, Stephen; Skinner, Wesley; Mullin, James [Applied Materials, Inc., Varian Semiconductor Equipment Business Unit, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

    2014-02-15

    In this paper, we introduce the Solion ion source for high-throughput solar cell doping. As the source power is increased to enable higher throughput, negative effects degrade the lifetime of the plasma chamber and the extraction electrodes. In order to improve efficiency, we have explored a wide range of electron energies and determined the conditions which best suit production. To extend the lifetime of the source we have developed an in situ cleaning method using only existing hardware. With these combinations, source life-times of >200 h for phosphorous and >100 h for boron ion beams have been achieved while maintaining 1100 cell-per-hour production.

  5. Explosive mixture of high power and high total energy content, and process for its manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Cook, M.A.; Udy, L.L.

    1973-05-10

    This explosive consists of a viscous suspension of an inorganic oxidizer, finely divided aluminum, water, and a liquid organic material miscible with water; a thickener may also be added. The mixture contains 45 to 55% of a strong inorganic oxidizer, of which at least two-thirds is ammonium nitrate; 32 to 43% aluminum powder; 11 to 18% or liquid, mostly water with an organic water-soluble liquid such as ethylene glycol; and a high temperature resistant, gel-forming thickener made of crosslinked guar gum and not crosslinked xanthane gum made from a polysaccharide through bacterial action.

  6. Compilation of radiation damage test data part III: materials used around high-energy accelerators

    CERN Document Server

    Beynel, P; Schönbacher, H; CERN. Geneva

    1982-01-01

    For pt.II see CERN report 79-08 (1979). This handbook gives the results of radiation damage tests on various engineering materials and components intended for installation in radiation areas of the CERN high-energy particle accelerators. It complements two previous volumes covering organic cable-insulating materials and thermoplastic and thermosetting resins.

  7. Detection of Fatigue Damage by Using High Frequency Nonlinear Laser Ultrasonic Signals

    International Nuclear Information System (INIS)

    Park, Seung Kyu; Park, Nak Kyu; Baik, Sung Hoon; Cheong, Yong Moo; Cha, Byung Heon

    2012-01-01

    The detection of fatigue damage for the components of a nuclear power plant is one of key techniques to prevent a catastrophic accident and the subsequent severe losses. Specifically, it is preferred to detect at an early stage of the fatigue damage. If the fatigue damage that is in danger of growing into a fracture is accurately detected, an appropriate treatment could be carried out to improve the condition. Although most engineers and designers take precautions against fatigue, some breakdowns of nuclear power plant components still occur due to fatigue damage. It is considered that ultrasound testing technique is the most promising method to detect the fatigue damage in many nondestructive testing methods. Laser ultrasound has attracted attention as a noncontact testing technique. Especially, laser ultrasonic signal has wide band frequency spectrum which can provide more accurate information for a testing material. The conventional linear ultrasonic technique is sensitive to gross defects or opened cracks whereas it is less sensitive to evenly distributed micro-cracks or degradation. An alternative technique to overcome this limitation is nonlinear ultrasound. The principal difference between linear and nonlinear technique is that in the latter the existence and characteristics of defects are often related to an acoustic signal whose frequency differs from that of the input signal. This is related to the radiation and propagation of finite amplitude, especially high power, ultrasound and its interaction with discontinuities, such as cracks, interfaces and voids. Since material failure or degradation is usually preceded by some kind of nonlinear mechanical behavior before significant plastic deformation or material damage occurs. The presence of nonlinear terms in the wave equation causes intense acoustic waves to generate new waves at frequencies which are multiples of the initial sound wave frequency. The nonlinear effect can exert a strong effect on the

  8. Radiation Damage Observations in the ATLAS Pixel Detector Using the High Voltage Delivery System

    CERN Document Server

    Toms, K

    2011-01-01

    We describe the implementation of radiation damage monitoring using leakage current measurement of the silicon pixel sensors provided by the circuits of the ATLAS Pixel Detector high voltage delivery (HVPP4) system. The dependence of the leakage current upon the integrated luminosity for several temperature scenarios is presented. Based on the analysis we have determined the sensitivity specifications for a Current Measurement System. The status of the system and the first measurement of the radiation damage corresponding to 2--4 fb$^{-1}$ of integrated luminosity are presented, as well as the comparison with the theoretical model.

  9. Application of advanced diffraction based optical metrology overlay capabilities for high-volume manufacturing

    Science.gov (United States)

    Chen, Kai-Hsiung; Huang, Guo-Tsai; Hsieh, Hung-Chih; Ni, Wei-Feng; Chuang, S. M.; Chuang, T. K.; Ke, Chih-Ming; Huang, Jacky; Rao, Shiuan-An; Cumurcu Gysen, Aysegul; d'Alfonso, Maxime; Yueh, Jenny; Izikson, Pavel; Soco, Aileen; Wu, Jon; Nooitgedagt, Tjitte; Ottens, Jeroen; Kim, Yong Ho; Ebert, Martin

    2017-03-01

    On-product overlay requirements are becoming more challenging with every next technology node due to the continued decrease of the device dimensions and process tolerances. Therefore, current and future technology nodes require demanding metrology capabilities such as target designs that are robust towards process variations and high overlay measurement density (e.g. for higher order process corrections) to enable advanced process control solutions. The impact of advanced control solutions based on YieldStar overlay data is being presented in this paper. Multi patterning techniques are applied for critical layers and leading to additional overlay measurement demands. The use of 1D process steps results in the need of overlay measurements relative to more than one layer. Dealing with the increased number of overlay measurements while keeping the high measurement density and metrology accuracy at the same time presents a challenge for high volume manufacturing (HVM). These challenges are addressed by the capability to measure multi-layer targets with the recently introduced YieldStar metrology tool, YS350. On-product overlay results of such multi-layers and standard targets are presented including measurement stability performance.

  10. High Strength and Ductility of Additively Manufactured 316L Stainless Steel Explained

    Science.gov (United States)

    Shamsujjoha, Md.; Agnew, Sean R.; Fitz-Gerald, James M.; Moore, William R.; Newman, Tabitha A.

    2018-04-01

    Structure-property relationships of an additively manufactured 316L stainless steel were explored. A scanning electron microscope and electron backscattered diffraction (EBSD) analysis revealed a fine cellular-dendritic (0.5 to 2 μm) substructure inside large irregularly shaped grains ( 100 μm). The cellular structure grows along the crystallographic directions. However, texture analysis revealed that the main texture component is inclined by 15 deg from the building direction. X-ray diffraction line profile analysis indicated a high dislocation density of 1 × 1015 m-2 in the as-built material, which correlates well with the observed EBSD microstructure and high-yield strength, via the traditional Taylor hardening equation. Significant variations in strain hardening behavior and ductility were observed for the horizontal (HB) and vertical (VB) built samples. Ductility of HB and VB samples measured 49 and 77 pct, respectively. The initial growth texture and subsequent texture evolution during tensile deformation are held responsible for the observed anisotropy. Notably, EBSD analysis of deformed samples showed deformation twins, which predominately form in the grains with aligned parallel to the loading direction. The VB samples showed higher twinning activity, higher strain hardening rates at high strain, and therefore, higher ductility. Analysis of annealed samples revealed that the observed microstructures and properties are thermally stable, with only a moderate decrease in strength and very similar levels of ductility and anisotropy, compared with the as-built condition.

  11. High Temperature Thermoplastic Additive Manufacturing Using Low-Cost, Open-Source Hardware

    Science.gov (United States)

    Gardner, John M.; Stelter, Christopher J.; Yashin, Edward A.; Siochi, Emilie J.

    2016-01-01

    Additive manufacturing (or 3D printing) via Fused Filament Fabrication (FFF), also known as Fused Deposition Modeling (FDM), is a process where material is placed in specific locations layer-by-layer to create a complete part. Printers designed for FFF build parts by extruding a thermoplastic filament from a nozzle in a predetermined path. Originally developed for commercial printers, 3D printing via FFF has become accessible to a much larger community of users since the introduction of Reprap printers. These low-cost, desktop machines are typically used to print prototype parts or novelty items. As the adoption of desktop sized 3D printers broadens, there is increased demand for these machines to produce functional parts that can withstand harsher conditions such as high temperature and mechanical loads. Materials meeting these requirements tend to possess better mechanical properties and higher glass transition temperatures (Tg), thus requiring printers with high temperature printing capability. This report outlines the problems and solutions, and includes a detailed description of the machine design, printing parameters, and processes specific to high temperature thermoplastic 3D printing.

  12. The assessment of bond strength between heat damaged concrete and high strength fibre reinforced concrete

    Science.gov (United States)

    Zahid, M. Z. A. Mohd; Muhamad, K.

    2017-09-01

    The aim of this study is to assess the bond strength between heat damaged concrete and high strength fibre reinforced concrete (HPFRC). Firstly, this paper presents the various steps taken to prepare the HPFRC with self-compacting property. The minimum targeted slump flow is 600 mm and minimum targeted compressive strength is 80 MPa. The key mix variables considered are such as type of superplasticizer, water cement ratio and silica fume content. Then, the bond strength between the heat damaged concrete with HPFRC was examined. The experimental parameters are heating temperature, surface treatment technique and curing method and the results show that, all experimental parameters are significantly affected the bond strength between heat damaged concrete and HPFRC.

  13. Assessment of damage domains of the High-Temperature Engineering Test Reactor (HTTR)

    International Nuclear Information System (INIS)

    Flores, Alain; Izquierdo, José María; Tuček, Kamil; Gallego, Eduardo

    2014-01-01

    Highlights: • We developed an adequate model for the identification of damage domains of the HTTR. • We analysed an anticipated operational transient, using the HTTR5+/GASTEMP code. • We simulated several transients of the same sequence. • We identified the corresponding damage domains using two methods. • We calculated exceedance frequency using the two methods. - Abstract: This paper presents an assessment analysis of damage domains of the 30 MW th prototype High-Temperature Engineering Test Reactor (HTTR) operated by the Japan Atomic Energy Agency (JAEA). For this purpose, an in-house deterministic risk assessment computational tool was developed based on the Theory of Stimulated Dynamics (TSD). To illustrate the methodology and applicability of the developed modelling approach, assessment results of a control rod (CR) withdrawal accident during subcritical conditions are presented and compared with those obtained by the JAEA

  14. Assessment of Mechanical Properties and Damage of High Performance Concrete Subjected to Magnesium Sulfate Environment

    Directory of Open Access Journals (Sweden)

    Sheng Cang

    2017-01-01

    Full Text Available Sulfate attack is one of the most important problems affecting concrete structures, especially magnesium sulfate attack. This paper presents an investigation on the mechanical properties and damage evolution of high performance concrete (HPC with different contents of fly ash exposure to magnesium sulfate environment. The microstructure, porosity, mass loss, dimensional variation, compressive strength, and splitting tensile strength of HPC were investigated at various erosion times up to 392 days. The ultrasonic pulse velocity (UPV propagation in HPC at different erosion time was determined by using ultrasonic testing technique. A relationship between damage and UPV of HPC was derived according to damage mechanics, and a correlation between the damage of HPC and erosion time was obtained eventually. The results indicated that (1 the average increasing amplitude of porosity for HPCs was 34.01% before and after exposure to magnesium sulfate solution; (2 the damage evolution of HPCs under sulfate attack could be described by an exponential fitting; (3 HPC containing 20% fly ash had the strongest resistance to magnesium sulfate attack.

  15. Improved assay for thymine base damage in E. coli using high performance liquid chromatography

    International Nuclear Information System (INIS)

    Claycamp, H.G.

    1985-01-01

    A simple high performance liquid chromatography (HPLC) technique has been established for the simultaneous assay of thymine and thymidine radiation damage products. The HPLC procedure uses an isocratic mobile phase of 4% acetonitrile in 0.2 M ammonium dihydrogen phosphate (pH 5.0), a reversed-phase octadecylsilicate (5 micro-spherical packing) 0.45 x 25 cm column, and a variable wavelength UV detector. This procedure affords much better resolution than other published procedures that use 10 micron columns or separate assays for bases and nucleosides. For example, irradiation of 5 x 10 -3 M thymidine solutions have been performed to calibrate the system for base damage assays in E. coli. This yields up to 15 resolvable residues within 20 minutes. Sensitivity of the system (at 2210 nm) for 5,6- dihydrothymine (DHT) is about 10 -10 moles. Preliminary results show that this translates to about 0.4 DHT residues per 10 6 daltons of E. coli DNA. This is comparable to the sensitivities of monoclonal assays to thymine damage products that have recently been reported by others. Since it is feasible that the sensitivity of this system can be improved by 2-3 times, this HPLC technique should provide a simple and rapid means of detecting E. coli base damage release and base damage in nucleoside hydrolysates of DNA

  16. Methodology for determining void swelling at very high damage under ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Getto, E., E-mail: embecket@umich.edu [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Sun, K. [Department of Materials Science Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Taller, S.; Monterrosa, A.M.; Jiao, Z. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Was, G.S. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Department of Materials Science Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

    2016-08-15

    At very high damage levels in ion irradiated samples, the decrease in effective density of the irradiated material due to void swelling can lead to errors in quantifying swelling. HT9 was pre-implanted with 10 appm He and subjected to a raster-scanned beam with a damage rate of ∼1 × 10{sup −3} dpa/s at 460{sup o}C. Voids were characterized from 0 to 1300 nm. Fixed damage rate and fixed depth methods were developed to account for damage-dependent porosity increase and resulting dependence on depth. The fixed depth method was more appropriate as it limits undue effects from the injected interstitial while maintaining a usable void distribution. By keeping the depth fixed and accounting for the change in damage rate due to reduced density, the steady state swelling rate was 10% higher than calculation of swelling from raw data. This method is easily translatable to other materials, ion types and energies and limits the impact of the injected interstitial.

  17. High EDSS can predict risk for upper urinary tract damage in patients with multiple sclerosis.

    Science.gov (United States)

    Ineichen, Benjamin V; Schneider, Marc P; Hlavica, Martin; Hagenbuch, Niels; Linnebank, Michael; Kessler, Thomas M

    2018-04-01

    Neurogenic lower urinary tract dysfunction (NLUTD) is very common in patients with multiple sclerosis (MS), and it might jeopardize renal function and thereby increase mortality. Although there are well-known urodynamic risk factors for upper urinary tract damage, no clinical prediction parameters are available. We aimed to assess clinical parameters potentially predicting urodynamic risk factors for upper urinary tract damage. A consecutive series of 141 patients with MS referred from neurologists for primary neuro-urological work-up including urodynamics were prospectively evaluated. Clinical parameters taken into account were age, sex, duration, and clinical course of MS and Expanded Disability Status Scale (EDSS). Multivariate modeling revealed EDSS as a clinical parameter significantly associated with urodynamic risk factors for upper urinary tract damage (odds ratio = 1.34, 95% confidence interval (CI) = 1.06-1.71, p = 0.02). Using receiver operator characteristic (ROC) curves, an EDSS of 5.0 as cutoff showed a sensitivity of 86%-87% and a specificity of 52% for at least one urodynamic risk factor for upper urinary tract damage. High EDSS is significantly associated with urodynamic risk factors for upper urinary tract damage and allows a risk-dependent stratification in daily neurological clinical practice to identify MS patients requiring further neuro-urological assessment and treatment.

  18. The ManuFuture road: towards competitive and sustainable high-adding-value manufacturing

    National Research Council Canada - National Science Library

    Jovane, Francesco; Westkämper, E; Williams, D. J

    2009-01-01

    ... is still leading the global trade market. Key issues, from globalization to climate change, are challenging manufacturing in advanced as well as emerging countries. Hence, manufacturing is getting back to the political agendas and the awareness of stakeholders is rising. In Europe key issues may lead to disruptive changes in the socio-economic syst...

  19. Novel high-fidelity realistic explosion damage simulation for urban environments

    Science.gov (United States)

    Liu, Xiaoqing; Yadegar, Jacob; Zhu, Youding; Raju, Chaitanya; Bhagavathula, Jaya

    2010-04-01

    Realistic building damage simulation has a significant impact in modern modeling and simulation systems especially in diverse panoply of military and civil applications where these simulation systems are widely used for personnel training, critical mission planning, disaster management, etc. Realistic building damage simulation should incorporate accurate physics-based explosion models, rubble generation, rubble flyout, and interactions between flying rubble and their surrounding entities. However, none of the existing building damage simulation systems sufficiently faithfully realize the criteria of realism required for effective military applications. In this paper, we present a novel physics-based high-fidelity and runtime efficient explosion simulation system to realistically simulate destruction to buildings. In the proposed system, a family of novel blast models is applied to accurately and realistically simulate explosions based on static and/or dynamic detonation conditions. The system also takes account of rubble pile formation and applies a generic and scalable multi-component based object representation to describe scene entities and highly scalable agent-subsumption architecture and scheduler to schedule clusters of sequential and parallel events. The proposed system utilizes a highly efficient and scalable tetrahedral decomposition approach to realistically simulate rubble formation. Experimental results demonstrate that the proposed system has the capability to realistically simulate rubble generation, rubble flyout and their primary and secondary impacts on surrounding objects including buildings, constructions, vehicles and pedestrians in clusters of sequential and parallel damage events.

  20. Lifetime laser damage performance of β-Ga2O3 for high power applications

    Directory of Open Access Journals (Sweden)

    Jae-Hyuck Yoo

    2018-03-01

    Full Text Available Gallium oxide (Ga2O3 is an emerging wide bandgap semiconductor with potential applications in power electronics and high power optical systems where gallium nitride and silicon carbide have already demonstrated unique advantages compared to gallium arsenide and silicon-based devices. Establishing the stability and breakdown conditions of these next-generation materials is critical to assessing their potential performance in devices subjected to large electric fields. Here, using systematic laser damage performance tests, we establish that β-Ga2O3 has the highest lifetime optical damage performance of any conductive material measured to date, above 10 J/cm2 (1.4 GW/cm2. This has direct implications for its use as an active component in high power laser systems and may give insight into its utility for high-power switching applications. Both heteroepitaxial and bulk β-Ga2O3 samples were benchmarked against a heteroepitaxial gallium nitride sample, revealing an order of magnitude higher optical lifetime damage threshold for β-Ga2O3. Photoluminescence and Raman spectroscopy results suggest that the exceptional damage performance of β-Ga2O3 is due to lower absorptive defect concentrations and reduced epitaxial stress.

  1. Lifetime laser damage performance of β -Ga2O3 for high power applications

    Science.gov (United States)

    Yoo, Jae-Hyuck; Rafique, Subrina; Lange, Andrew; Zhao, Hongping; Elhadj, Selim

    2018-03-01

    Gallium oxide (Ga2O3) is an emerging wide bandgap semiconductor with potential applications in power electronics and high power optical systems where gallium nitride and silicon carbide have already demonstrated unique advantages compared to gallium arsenide and silicon-based devices. Establishing the stability and breakdown conditions of these next-generation materials is critical to assessing their potential performance in devices subjected to large electric fields. Here, using systematic laser damage performance tests, we establish that β-Ga2O3 has the highest lifetime optical damage performance of any conductive material measured to date, above 10 J/cm2 (1.4 GW/cm2). This has direct implications for its use as an active component in high power laser systems and may give insight into its utility for high-power switching applications. Both heteroepitaxial and bulk β-Ga2O3 samples were benchmarked against a heteroepitaxial gallium nitride sample, revealing an order of magnitude higher optical lifetime damage threshold for β-Ga2O3. Photoluminescence and Raman spectroscopy results suggest that the exceptional damage performance of β-Ga2O3 is due to lower absorptive defect concentrations and reduced epitaxial stress.

  2. Neutron irradiation damage of nuclear graphite studied by high-resolution transmission electron microscopy and Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, R. [Dalton Cumbrian Facility, Dalton Nuclear Institute, The University of Manchester, Westlakes Science & Technology Park, Moor Row, Whitehaven, Cumbria, CA24 3HA (United Kingdom); Jones, A.N., E-mail: Abbie.Jones@manchester.ac.uk [Nuclear Graphite Research Group, School of MACE, The University of Manchester, Manchester, M13 9PL (United Kingdom); McDermott, L.; Marsden, B.J. [Nuclear Graphite Research Group, School of MACE, The University of Manchester, Manchester, M13 9PL (United Kingdom)

    2015-12-15

    Nuclear graphite components are produced from polycrystalline artificial graphite manufacture from a binder and filler coke with approximately 20% porosity. During the operational lifetime, nuclear graphite moderator components are subjected to fast neutron irradiation which contributes to the change of material and physical properties such as thermal expansion co-efficient, young's modulus and dimensional change. These changes are directly driven by irradiation-induced changes to the crystal structure as reflected through the bulk microstructure. It is therefore of critical importance that these irradiation changes and there implication on component property changes are fully understood. This work examines a range of irradiated graphite samples removed from the British Experimental Pile Zero (BEPO) reactor; a low temperature, low fluence, air-cooled Materials Test Reactor which operated in the UK. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) have been employed to characterise the effect of increased irradiation fluence on graphite microstructure and understand low temperature irradiation damage processes. HRTEM confirms the structural damage of the crystal lattice caused by irradiation attributed to a high number of defects generation with the accumulation of dislocation interactions at nano-scale range. Irradiation-induced crystal defects, lattice parameters and crystallite size compared to virgin nuclear graphite are characterised using selected area diffraction (SAD) patterns in TEM and Raman Spectroscopy. The consolidated ‘D’peak in the Raman spectra confirms the formation of in-plane point defects and reflected as disordered regions in the lattice. The reduced intensity and broadened peaks of ‘G’ and ‘D’ in the Raman and HRTEM results confirm the appearance of turbulence and disordering of the basal planes whilst maintaining their coherent layered graphite structure. - Highlights: • Irradiated graphite

  3. Neutron irradiation damage of nuclear graphite studied by high-resolution transmission electron microscopy and Raman spectroscopy

    International Nuclear Information System (INIS)

    Krishna, R.; Jones, A.N.; McDermott, L.; Marsden, B.J.

    2015-01-01

    Nuclear graphite components are produced from polycrystalline artificial graphite manufacture from a binder and filler coke with approximately 20% porosity. During the operational lifetime, nuclear graphite moderator components are subjected to fast neutron irradiation which contributes to the change of material and physical properties such as thermal expansion co-efficient, young's modulus and dimensional change. These changes are directly driven by irradiation-induced changes to the crystal structure as reflected through the bulk microstructure. It is therefore of critical importance that these irradiation changes and there implication on component property changes are fully understood. This work examines a range of irradiated graphite samples removed from the British Experimental Pile Zero (BEPO) reactor; a low temperature, low fluence, air-cooled Materials Test Reactor which operated in the UK. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) have been employed to characterise the effect of increased irradiation fluence on graphite microstructure and understand low temperature irradiation damage processes. HRTEM confirms the structural damage of the crystal lattice caused by irradiation attributed to a high number of defects generation with the accumulation of dislocation interactions at nano-scale range. Irradiation-induced crystal defects, lattice parameters and crystallite size compared to virgin nuclear graphite are characterised using selected area diffraction (SAD) patterns in TEM and Raman Spectroscopy. The consolidated ‘D’peak in the Raman spectra confirms the formation of in-plane point defects and reflected as disordered regions in the lattice. The reduced intensity and broadened peaks of ‘G’ and ‘D’ in the Raman and HRTEM results confirm the appearance of turbulence and disordering of the basal planes whilst maintaining their coherent layered graphite structure. - Highlights: • Irradiated graphite exhibits

  4. Impacts of Academic R&D on High-Tech Manufacturing Products: Tentative Evidence from Supercomputer Data

    Science.gov (United States)

    Le, Thanh; Tang, Kam Ki

    2015-01-01

    This paper empirically examines the impact of academic research on high-tech manufacturing growth of 28 Organisation for Economic Co-operation and Development (OECD) and emerging countries over the 1991-2005 period. A standard research and development (R&D) expenditure based measure is found to be too general to capture the input in high-tech…

  5. Conference Analysis Report of Assessments on Defect and Damage for a High Temperature Structure

    International Nuclear Information System (INIS)

    Lee, Hyeong Yeon

    2008-11-01

    This report presents the analysis on the state-of-the-art research trends on creep-fatigue damage, defect assessment of high temperature structure, development of heat resistant materials and their behavior at high temperature based on the papers presented in the two international conferences of ASME PVP 2008 which was held in Chicago in July 2008 and CF-5(5th International Conference on Creep, Fatigue and Creep-Fatigue) which was held in Kalpakkam, India in September 2008

  6. Conference Analysis Report of Assessments on Defect and Damage for a High Temperature Structure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyeong Yeon

    2008-11-15

    This report presents the analysis on the state-of-the-art research trends on creep-fatigue damage, defect assessment of high temperature structure, development of heat resistant materials and their behavior at high temperature based on the papers presented in the two international conferences of ASME PVP 2008 which was held in Chicago in July 2008 and CF-5(5th International Conference on Creep, Fatigue and Creep-Fatigue) which was held in Kalpakkam, India in September 2008.

  7. Influence of the Manufacturing Process on Defects in the Galvanized Coating of High Carbon Steel Wires.

    Science.gov (United States)

    Gelfi, Marcello; Solazzi, Luigi; Poli, Sandro

    2017-03-06

    This study is a detailed failure analysis of galvanized high carbon steel wires, which developed coating cracks during the torsion test performed as a quality control at the end of the manufacturing process. Careful visual inspections showed that the cracks are already present in the coating before the torsion test. In order to explain the origin of these cracks, systematic metallographic investigations were performed by means of optical and scanning electron microscope on both the wires and the rods that have been cold drawn to produce the wire. The chemical composition of the galvanized coatings was evaluated by means of energy dispersive spectroscopy. Micro bidimensional X-ray diffraction experiments were also performed to measure the residual stresses in the galvanized coating. The results showed that the failure is related to two main factors: the relatively high content of silicon in the steel and the unsuitable cooling rate of the rods at the exit from the galvanizing bath. The mechanism proposed to explain the origin of the defects was supported by Finite Elements Methods simulations and verified with in-plant tests. The proper countermeasures were then applied and the problem successfully solved.

  8. Influence of the Manufacturing Process on Defects in the Galvanized Coating of High Carbon Steel Wires

    Directory of Open Access Journals (Sweden)

    Marcello Gelfi

    2017-03-01

    Full Text Available This study is a detailed failure analysis of galvanized high carbon steel wires, which developed coating cracks during the torsion test performed as a quality control at the end of the manufacturing process. Careful visual inspections showed that the cracks are already present in the coating before the torsion test. In order to explain the origin of these cracks, systematic metallographic investigations were performed by means of optical and scanning electron microscope on both the wires and the rods that have been cold drawn to produce the wire. The chemical composition of the galvanized coatings was evaluated by means of energy dispersive spectroscopy. Micro bidimensional X-ray diffraction experiments were also performed to measure the residual stresses in the galvanized coating. The results showed that the failure is related to two main factors: the relatively high content of silicon in the steel and the unsuitable cooling rate of the rods at the exit from the galvanizing bath. The mechanism proposed to explain the origin of the defects was supported by Finite Elements Methods simulations and verified with in-plant tests. The proper countermeasures were then applied and the problem successfully solved.

  9. Direct Numerical Simulations of Microstructure Effects During High-Rate Loading of Additively Manufactured Metals

    Science.gov (United States)

    Battaile, Corbett; Owen, Steven; Moore, Nathan

    2017-06-01

    The properties of most engineering materials depend on the characteristics of internal microstructures and defects. In additively manufactured (AM) metals, these can include polycrystalline grains, impurities, phases, and significant porosity that qualitatively differ from conventional engineering materials. The microscopic details of the interactions between these internal defects, and the propagation of applied loads through the body, act in concert to dictate macro-observable properties like strength and compressibility. In this work, we used Sandia's ALEGRA finite element software to simulate the high-strain-rate loading of AM metals from laser engineered net shaping (LENS) and thermal spraying. The microstructural details of the material were represented explicitly, such that internal features like second phases and pores are captured and meshed as individual entities in the computational domain. We will discuss the dependence of the high-strain-rate mechanical properties on microstructural characteristics such as the shapes, sizes, and volume fractions of second phases and pores. In addition, we will examine how the details of the microstructural representation affect the microscopic material response to dynamic loads, and the effects of using ``stair-step'' versus conformal interfaces smoothed via the SCULPT tool in Sandia's CUBIT software. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US DOE NNSA under contract DE-AC04-94AL85000.

  10. Implementation of machine learning for high-volume manufacturing metrology challenges (Conference Presentation)

    Science.gov (United States)

    Timoney, Padraig; Kagalwala, Taher; Reis, Edward; Lazkani, Houssam; Hurley, Jonathan; Liu, Haibo; Kang, Charles; Isbester, Paul; Yellai, Naren; Shifrin, Michael; Etzioni, Yoav

    2018-03-01

    In recent years, the combination of device scaling, complex 3D device architecture and tightening process tolerances have strained the capabilities of optical metrology tools to meet process needs. Two main categories of approaches have been taken to address the evolving process needs. In the first category, new hardware configurations are developed to provide more spectral sensitivity. Most of this category of work will enable next generation optical metrology tools to try to maintain pace with next generation process needs. In the second category, new innovative algorithms have been pursued to increase the value of the existing measurement signal. These algorithms aim to boost sensitivity to the measurement parameter of interest, while reducing the impact of other factors that contribute to signal variability but are not influenced by the process of interest. This paper will evaluate the suitability of machine learning to address high volume manufacturing metrology requirements in both front end of line (FEOL) and back end of line (BEOL) sectors from advanced technology nodes. In the FEOL sector, initial feasibility has been demonstrated to predict the fin CD values from an inline measurement using machine learning. In this study, OCD spectra were acquired after an etch process that occurs earlier in the process flow than where the inline CD is measured. The fin hard mask etch process is known to impact the downstream inline CD value. Figure 1 shows the correlation of predicted CD vs downstream inline CD measurement obtained after the training of the machine learning algorithm. For BEOL, machine learning is shown to provide an additional source of information in prediction of electrical resistance from structures that are not compatible for direct copper height measurement. Figure 2 compares the trench height correlation to electrical resistance (Rs) and the correlation of predicted Rs to the e-test Rs value for a far back end of line (FBEOL) metallization level

  11. Acoustic Emission and Damage Characteristics of Granite Subjected to High Temperature

    Directory of Open Access Journals (Sweden)

    X. L. Xu

    2018-01-01

    Full Text Available Acoustic emission (AE signals can be detected from rocks under the effect of temperature and loading, which can be used to reflect rock damage evolution process and predict rock fracture. In this paper, uniaxial compression tests of granite at high temperatures from 25°C to 1000°C were carried out, and AE signals were monitored simultaneously. The results indicated that AE ring count rate shows the law of “interval burst” and “relatively calm,” which can be explained from the energy point of view. From 25°C to 1000°C, the rock failure mode changes from single splitting failure to multisplitting failure, and then to incomplete shear failure, ideal shear failure, and double shear failure, until complete integral failure. Thermal damage (DT defined by the elastic modulus shows logistic increase with the rise of temperature. Mechanical damage (DM derived by the AE ring count rate can be divided into initial stage, stable stage, accelerated stage, and destructive stage. Total damage (D increases with the rise of strain, which is corresponding to the stress-strain curve at various temperatures. Using AE data, we can further analyze the mechanism of deformation and fracture of rock, which helps to gather useful data for predicting rock stability at high temperatures.

  12. High variation in manufacturer-declared serving size of packaged discretionary foods in Australia.

    Science.gov (United States)

    Haskelberg, Hila; Neal, Bruce; Dunford, Elizabeth; Flood, Victoria; Rangan, Anna; Thomas, Beth; Cleanthous, Xenia; Trevena, Helen; Zheng, Jazzmin Miaobing; Louie, Jimmy Chun Yu; Gill, Timothy; Wu, Jason H Y

    2016-05-28

    Despite the potential of declared serving size to encourage appropriate portion size consumption, most countries including Australia have not developed clear reference guidelines for serving size. The present study evaluated variability in manufacturer-declared serving size of discretionary food and beverage products in Australia, and how declared serving size compared with the 2013 Australian Dietary Guideline (ADG) standard serve (600 kJ). Serving sizes were obtained from the Nutrition Information Panel for 4466 packaged, discretionary products in 2013 at four large supermarkets in Sydney, Australia, and categorised into fifteen categories in line with the 2013 ADG. For unique products that were sold in multiple package sizes, the percentage difference between the minimum and the maximum serving size across different package sizes was calculated. A high variation in serving size was found within the majority of food and beverage categories - for example, among 347 non-alcoholic beverages (e.g. soft drinks), the median for serving size was 250 (interquartile range (IQR) 250, 355) ml (range 100-750 ml). Declared serving size for unique products that are available in multiple package sizes also showed high variation, particularly for chocolate-based confectionery, with median percentage difference between minimum and maximum serving size of 183 (IQR 150) %. Categories with a high proportion of products that exceeded the 600 kJ ADG standard serve included cakes and muffins, pastries and desserts (≥74 % for each). High variability in declared serving size may confound interpretation and understanding of consumers interested in standardising and controlling their portion selection. Future research is needed to assess if and how standardising declared serving size might affect consumer behaviour.

  13. High-Temperature Performance and Multiscale Damage Mechanisms of Hollow Cellulose Fiber-Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Liping Guo

    2016-01-01

    Full Text Available Spalling resistance properties and their damage mechanisms under high temperatures are studied in hollow cellulose fiber-reinforced concrete (CFRC used in tunnel structures. Measurements of mass loss, relative dynamic elastic modulus, compressive strength, and splitting tensile strength of CFRC held under high temperatures (300, 600, 800, and 1050°C for periods of 2.5, 4, and 5.5 h were carried out. The damage mechanism was analyzed using scanning electron microscopy, mercury intrusion porosimetry, thermal analysis, and X-ray diffraction phase analysis. The results demonstrate that cellulose fiber can reduce the performance loss of concrete at high temperatures; the effect of holding time on the performance is more noticeable below 600°C. After exposure to high temperatures, the performance of ordinary concrete deteriorates faster and spalls at 700–800°C; in contrast, cellulose fiber melts at a higher temperature, leaving a series of channels in the matrix that facilitate the release of the steam pressure inside the CFRC. Hollow cellulose fibers can thereby slow the damage caused by internal stress and improve the spalling resistance of concrete under high temperatures.

  14. High-damage-resistant tungsten disulfide saturable absorber mirror for passively Q-switched fiber laser.

    Science.gov (United States)

    Chen, Hao; Chen, YuShan; Yin, Jinde; Zhang, Xuejun; Guo, Tuan; Yan, Peiguang

    2016-07-25

    In this paper, we demonstrate a high-damage-resistant tungsten disulfide saturable absorber mirror (WS2-SAM) fabricated by magnetron sputtering technique. The WS2-SAM has an all-fiber-integrated configuration and high-damage-resistant merit because the WS2 layer is protected by gold film so as to avoid being oxidized and destroyed at high pump power. Employing the WS2-SAM in an Erbium-doped fiber laser (EDFL) with linear cavity, the stable Q-switching operation is achieved at central wavelength of 1560 nm, with the repetition rates ranging from 29.5 kHz to 367.8 kHz and the pulse duration ranging from 1.269 μs to 154.9 ns. For the condition of the maximum pump power of 600 mW, the WS2-SAM still works stably with an output power of 25.2 mW, pulse energy of 68.5 nJ, and signal-noise-ratio of 42 dB. The proposed WS2-SAM configuration provides a promising solution for advanced pulsed fiber lasers with the characteristics of high damage resistance, high output energy, and wide tunable frequency.

  15. Implementing high-temperature short-time media treatment in commercial-scale cell culture manufacturing processes.

    Science.gov (United States)

    Pohlscheidt, Michael; Charaniya, Salim; Kulenovic, Fikret; Corrales, Mahalia; Shiratori, Masaru; Bourret, Justin; Meier, Steven; Fallon, Eric; Kiss, Robert

    2014-04-01

    The production of therapeutic proteins by mammalian cell culture is complex and sets high requirements for process, facility, and equipment design, as well as rigorous regulatory and quality standards. One particular point of concern and significant risk to supply chain is the susceptibility to contamination such as bacteria, fungi, mycoplasma, and viruses. Several technologies have been developed to create barriers for these agents to enter the process, e.g. filtration, UV inactivation, and temperature inactivation. However, if not implemented during development of the manufacturing process, these types of process changes can have significant impact on process performance if not managed appropriately. This article describes the implementation of the high-temperature short-time (HTST) treatment of cell culture media as an additional safety barrier against adventitious agents during the transfer of a large-scale commercial cell culture manufacturing process. The necessary steps and experiments, as well as subsequent results during qualification runs and routine manufacturing, are shown.

  16. Persistent DNA damage after high dose in vivo gamma exposure of minipig skin.

    Directory of Open Access Journals (Sweden)

    Emad A Ahmed

    Full Text Available Exposure to high doses of ionizing radiation (IR can lead to localized radiation injury of the skin and exposed cells suffer dsDNA breaks that may elicit cell death or stochastic changes. Little is known about the DNA damage response after high-dose exposure of the skin. Here, we investigate the cellular and DNA damage response in acutely irradiated minipig skin.IR-induced DNA damage, repair and cellular survival were studied in 15 cm(2 of minipig skin exposed in vivo to ~50 Co-60 γ rays. Skin biopsies of control and 4 h up to 96 days post exposure were investigated for radiation-induced foci (RIF formation using γ-H2AX, 53BP1, and active ATM-p immunofluorescence. High-dose IR induced massive γ-H2AX phosphorylation and high 53BP1 RIF numbers 4 h, 20 h after IR. As time progressed RIF numbers dropped to a low of 3-fold elevated at all subsequent time points. Replicating basal cells (Ki67+ were reduced 3 days post IR followed by increased proliferation and recovery of epidermal cellularity after 28 days.Acute high dose irradiation of minipig epidermis impaired stem cell replication and induced elevated apoptosis from 3 days onward. DNA repair cleared the high numbers of DBSs in skin cells, while RIFs that persisted in <1% cells marked complex and potentially lethal DNA damage up to several weeks after exposure. An elevated frequency of keratinocytes with persistent RIFs may thus serve as indicator of previous acute radiation exposure, which may be useful in the follow up of nuclear or radiological accident scenarios.

  17. Consistent manufacturing and quality control of a highly complex recombinant polyclonal antibody product for human therapeutic use.

    Science.gov (United States)

    Frandsen, Torben P; Naested, Henrik; Rasmussen, Søren K; Hauptig, Peter; Wiberg, Finn C; Rasmussen, Lone Kjaer; Jensen, Anne Marie Valentin; Persson, Pia; Wikén, Margareta; Engström, Anders; Jiang, Yun; Thorpe, Susan J; Förberg, Cecilia; Tolstrup, Anne B

    2011-09-01

    The beneficial effect of antibody therapy in human disease has become well established mainly for the treatment of cancer and immunological disorders. The inherent monospecificity of mAbs present limitations to mAb therapy which have become apparent notably in addressing complex entities like infectious agents or heterogenic endogenous targets. For such indications mixtures of antibodies comprising a combination of specificities would convey more potent biological effect which could translate into therapeutic efficacy. Recombinant polyclonal antibodies (rpAb) consisting of a defined number of well-characterized mAbs constitute a new class of target specific antibody therapy. We have developed a cost-efficient cell banking and single-batch manufacturing concept for the production of such products and demonstrate that a complex pAb composition, rozrolimupab, comprising 25 individual antibodies can be manufactured in a highly consistent manner in a scaled-up manufacturing process. We present a strategy for the release and characterization of antibody mixtures which constitute a complete series of chemistry, manufacturing, and control (CMC) analytical methods to address identity, purity, quantity, potency, and general characteristics. Finally we document selected quality attributes of rozrolimupab based on a battery of assays at the genetic-, protein-, and functional level and demonstrate that the manufactured rozrolimupab batches are highly pure and very uniform in their composition. Copyright © 2011 Wiley Periodicals, Inc.

  18. Extreme implanting in Si: A study of ion-induced damage at high temperature and high dose

    International Nuclear Information System (INIS)

    Holland, O.W.

    1994-01-01

    Ion-solid interactions near room temperature and below have been well studied in single-crystal Si. While this has led to a better understanding of the mechanisms responsible for nucleation and growth of lattice damage during irradiation, these studies have not, in general, been extended to high temperatures (e.g., >200 degrees C). This is the case despite the commercialization of ion beam technologies which utilize high-temperature processing, such as separation by implantation of oxygen (SIMOX). In this process, a silicon-on-insulator (SOI) material is produced by implanting a high dose of oxygen ions into a Si wafer to form a buried, stoichiometric oxide layer. Results will be presented of a study of damage accumulation during high-dose implantation of Si at elevated temperatures. In particular, O + -ions were used because of the potential impact of the results on the SIMOX technology. It will be shown that the nature of the damage accumulation at elevated temperatures is quite distinctive and portends the presence of a new mechanism, one which is only dominant under the extreme conditions encountered during ion beam synthesis (i.e., high temperature and high dose). This mechanism is discussed and shown to be quite general and not dependent on the chemical identity of the ions. Also, techniques for suppressing this mechanism by open-quotes defect engineeringclose quotes are discussed. Such techniques are technologically relevant because they offer the possibility of reducing the defect density of the SOI produced by SIMOX

  19. Continuous Digital Light Processing (cDLP): Highly Accurate Additive Manufacturing of Tissue Engineered Bone Scaffolds.

    Science.gov (United States)

    Dean, David; Jonathan, Wallace; Siblani, Ali; Wang, Martha O; Kim, Kyobum; Mikos, Antonios G; Fisher, John P

    2012-03-01

    Highly accurate rendering of the external and internal geometry of bone tissue engineering scaffolds effects fit at the defect site, loading of internal pore spaces with cells, bioreactor-delivered nutrient and growth factor circulation, and scaffold resorption. It may be necessary to render resorbable polymer scaffolds with 50 μm or less accuracy to achieve these goals. This level of accuracy is available using Continuous Digital Light processing (cDLP) which utilizes a DLP(®) (Texas Instruments, Dallas, TX) chip. One such additive manufacturing device is the envisionTEC (Ferndale, MI) Perfactory(®). To use cDLP we integrate a photo-crosslinkable polymer, a photo-initiator, and a biocompatible dye. The dye attenuates light, thereby limiting the depth of polymerization. In this study we fabricated scaffolds using the well-studied resorbable polymer, poly(propylene fumarate) (PPF), titanium dioxide (TiO(2)) as a dye, Irgacure(®) 819 (BASF [Ciba], Florham Park, NJ) as an initiator, and diethyl fumarate as a solvent to control viscosity.

  20. Development of manufacturing method of thermal-resisting concrete with highly synthesizing xonotolite

    International Nuclear Information System (INIS)

    Yamamoto, Takeshi; Hironaga, Michihiko

    2006-01-01

    Xonotolite is one of the most stable Ca-Si hydration compounds in the cementitious material. The authors have been developing anti-drying shrinkage concrete with focusing on the stable compounds, i.e. Tobermorite and Xonotolite. In this study, we proposed the manufacturing method of anti-drying shrinkage concrete with using low calcium/silica ratio cementitious material and applying autoclave curing. The compressive strength of proposed concrete was about 40N/mm 2 , and drying shrinkage under 110degC for 1 year was ranged from 0.04 to 0.06%. There was no amount released of combined water from the proposed concrete during exposure, so the stability of main synthesized compound in the proposed concrete was clarified. On the other hand, the conventional cementitious mortar showed from 0.1 to 0.13% of drying shrinkage and high amount release of combined water from the surface area of C-S-H colloid with resulting to widen the volume of pore among the colloid particle of C-S-H. (author)

  1. Experience feedback from high heat flux component manufacturing for Tore Supra

    International Nuclear Information System (INIS)

    Schlosser, J.; Durocher, A.; Huber, T.; Garin, P.; Schedler, B.; Agarici, G.

    2001-01-01

    Tore Supra is involved in flat tile carbon armoured plasma facing components (PFCs) since 1985. In 1997, a third generation of components, based on the original concept developed with Plansee Company, called active metal casting (AMC[reg]), has been launched. Since 1998, 660 elementary components for the toroidal pump limiter (TPL) are in production. The route of the manufacture is rather complex and many controls were requested all along the fabrication to insure a high reliability of the elements. One of the main controls is the final infrared (IR) test allowing to determine the quality of the bonding between the carbon fibre composite (CFC) tiles and the heat sink made of copper-chromium-zirconium alloy (CuCrZr). Although results for the first batch of elements were as expected (less than 5% rejected at the final test), unexpected defects appeared with the followings batches. Investigations on the fabrication processes underlined the importance of having a better heat treatment of the pieces in copper alloy (CuCrZr), however this was not sufficient to completely explain the observed defects

  2. Manufacture research of the test equipment to measure the dose rate in high radiation medium

    International Nuclear Information System (INIS)

    Phan Luong Tuan; Nguyen Van Sy; Nguyen Xuan Vinh; Dang Quang Bao; Nguyen Thanh Hung; Pham Minh Duc; Nguyen Xuan Truong

    2017-01-01

    Photodiode BPW34 is operated as a low voltage counter tubes. When the radiation rays go into the BPW34,they will create a pairs of electron and hole. If setting the reverse bias in to the BPW34, a pulse is achieved and it can be amplified and processed. The STM32 is the microcontroller family which is developed base on ARM processors. The STM32 incorporated many new features such as ADC, I2C, etc. With the connectional ability to other devices, the STM32 is proving its advantages in the development of equipment.The application of irradiation technology in the economy-society increases widespread as food irradiation, mutant irradiation, etc. Until now the calculation the high dose rate at Hanoi Irradiation Center is identified by the Fricke, ECB dosimeters. The dosimeters must be destroyed in order to serve for dose rate determination. Manufacture research the equipment for dose rate calculation support to determine dose rate directly through the equipment’s signal and this equipment can be used multiple. This equipment can be connected to other devices to control the irradiation process better via signals. (author)

  3. Automated High-Volume Manufacturing of Modular Photovoltaic Panel Assemblies for Space Solar Arrays, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Deployable Space Systems, Inc. (DSS) will focus the proposed SBIR Phase 2 program on the development and demonstration of an automated robotic manufacturing...

  4. Design-Based Innovation for Manufacturing Firm Success in High-Cost Operating Environments

    Directory of Open Access Journals (Sweden)

    Göran Roos

    The paper concludes that the design-based innovation paradigm is increasingly important within the manufacturing industry, but that its benefit can only be maximized if it is integrated with the other three value-creating approaches to innovation.

  5. Oxidative DNA damage and repair in skeletal muscle of humans exposed to high-altitude hypoxia

    International Nuclear Information System (INIS)

    Lundby, Carsten; Pilegaard, Henriette; Hall, Gerrit van; Sander, Mikael; Calbet, Jose; Loft, Steffen; Moeller, Peter

    2003-01-01

    Recent research suggests that high-altitude hypoxia may serve as a model for prolonged oxidative stress in healthy humans. In this study, we investigated the consequences of prolonged high-altitude hypoxia on the basal level of oxidative damage to nuclear DNA in muscle cells, a major oxygen-consuming tissue. Muscle biopsies from seven healthy humans were obtained at sea level and after 2 and 8 weeks of hypoxia at 4100 m.a.s.l. We found increased levels of strand breaks and endonuclease III-sensitive sites after 2 weeks of hypoxia, whereas oxidative DNA damage detected by formamidopyrimidine DNA glycosylase (FPG) protein was unaltered. The expression of 8-oxoguanine DNA glycosylase 1 (OGG1), determined by quantitative RT-PCR of mRNA levels did not significantly change during high-altitude hypoxia, although the data could not exclude a minor upregulation. The expression of heme oxygenase-1 (HO-1) was unaltered by prolonged hypoxia, in accordance with the notion that HO-1 is an acute stress response protein. In conclusion, our data indicate high-altitude hypoxia may serve as a good model for oxidative stress and that antioxidant genes are not upregulated in muscle tissue by prolonged hypoxia despite increased generation of oxidative DNA damage

  6. Recent advance in high manufacturing readiness level and high temperature CMOS mixed-signal integrated circuits on silicon carbide

    Science.gov (United States)

    Weng, M. H.; Clark, D. T.; Wright, S. N.; Gordon, D. L.; Duncan, M. A.; Kirkham, S. J.; Idris, M. I.; Chan, H. K.; Young, R. A. R.; Ramsay, E. P.; Wright, N. G.; Horsfall, A. B.

    2017-05-01

    A high manufacturing readiness level silicon carbide (SiC) CMOS technology is presented. The unique process flow enables the monolithic integration of pMOS and nMOS transistors with passive circuit elements capable of operation at temperatures of 300 °C and beyond. Critical to this functionality is the behaviour of the gate dielectric and data for high temperature capacitance-voltage measurements are reported for SiO2/4H-SiC (n and p type) MOS structures. In addition, a summary of the long term reliability for a range of structures including contact chains to both n-type and p-type SiC, as well as simple logic circuits is presented, showing function after 2000 h at 300 °C. Circuit data is also presented for the performance of digital logic devices, a 4 to 1 analogue multiplexer and a configurable timer operating over a wide temperature range. A high temperature micro-oven system has been utilised to enable the high temperature testing and stressing of units assembled in ceramic dual in line packages, including a high temperature small form-factor SiC based bridge leg power module prototype, operated for over 1000 h at 300 °C. The data presented show that SiC CMOS is a key enabling technology in high temperature integrated circuit design. In particular it provides the ability to realise sensor interface circuits capable of operating above 300 °C, accommodate shifts in key parameters enabling deployment in applications including automotive, aerospace and deep well drilling.

  7. High-fidelity Modeling of Local Effects of Damage for Derated Offshore Wind Turbines

    International Nuclear Information System (INIS)

    Richards, Phillip W; Griffith, D Todd; Hodges, Dewey H

    2014-01-01

    Offshore wind power production is an attractive clean energy option, but the difficulty of access can lead to expensive and rare opportunities for maintenance. As part of the Structural Health and Prognostics Management (SHPM) project at Sandia National Laboratories, smart loads management (controls) are investigated for their potential to increase the fatigue life of offshore wind turbine rotor blades. Derating refers to altering the rotor angular speed and blade pitch to limit power production and loads on the rotor blades. High- fidelity analysis techniques like 3D finite element modeling (FEM) should be used alongside beam models of wind turbine blades to characterize these control strategies in terms of their effect to mitigate fatigue damage and extend life of turbine blades. This study will consider a commonly encountered damage type for wind turbine blades, the trailing edge disbond, and show how FEM can be used to quantify the effect of operations and control strategies designed to extend the fatigue life of damaged blades. The Virtual Crack Closure Technique (VCCT) will be used to post-process the displacement and stress results to provide estimates of damage severity/criticality and provide a means to estimate the fatigue life under a given operations and control strategy

  8. High-fidelity Modeling of Local Effects of Damage for Derated Offshore Wind Turbines

    Science.gov (United States)

    Richards, Phillip W.; Griffith, D. Todd; Hodges, Dewey H.

    2014-06-01

    Offshore wind power production is an attractive clean energy option, but the difficulty of access can lead to expensive and rare opportunities for maintenance. As part of the Structural Health and Prognostics Management (SHPM) project at Sandia National Laboratories, smart loads management (controls) are investigated for their potential to increase the fatigue life of offshore wind turbine rotor blades. Derating refers to altering the rotor angular speed and blade pitch to limit power production and loads on the rotor blades. High- fidelity analysis techniques like 3D finite element modeling (FEM) should be used alongside beam models of wind turbine blades to characterize these control strategies in terms of their effect to mitigate fatigue damage and extend life of turbine blades. This study will consider a commonly encountered damage type for wind turbine blades, the trailing edge disbond, and show how FEM can be used to quantify the effect of operations and control strategies designed to extend the fatigue life of damaged blades. The Virtual Crack Closure Technique (VCCT) will be used to post-process the displacement and stress results to provide estimates of damage severity/criticality and provide a means to estimate the fatigue life under a given operations and control strategy.

  9. High and Low LET Radiation Differentially Induce Normal Tissue Damage Signals

    International Nuclear Information System (INIS)

    Niemantsverdriet, Maarten; Goethem, Marc-Jan van; Bron, Reinier; Hogewerf, Wytse; Brandenburg, Sytze; Langendijk, Johannes A.; Luijk, Peter van; Coppes, Robert P.

    2012-01-01

    Purpose: Radiotherapy using high linear energy transfer (LET) radiation is aimed at efficiently killing tumor cells while minimizing dose (biological effective) to normal tissues to prevent toxicity. It is well established that high LET radiation results in lower cell survival per absorbed dose than low LET radiation. However, whether various mechanisms involved in the development of normal tissue damage may be regulated differentially is not known. Therefore the aim of this study was to investigate whether two actions related to normal tissue toxicity, p53-induced apoptosis and expression of the profibrotic gene PAI-1 (plasminogen activator inhibitor 1), are differentially induced by high and low LET radiation. Methods and Materials: Cells were irradiated with high LET carbon ions or low LET photons. Cell survival assays were performed, profibrotic PAI-1 expression was monitored by quantitative polymerase chain reaction, and apoptosis was assayed by annexin V staining. Activation of p53 by phosphorylation at serine 315 and serine 37 was monitored by Western blotting. Transfections of plasmids expressing p53 mutated at serines 315 and 37 were used to test the requirement of these residues for apoptosis and expression of PAI-1. Results: As expected, cell survival was lower and induction of apoptosis was higher in high -LET irradiated cells. Interestingly, induction of the profibrotic PAI-1 gene was similar with high and low LET radiation. In agreement with this finding, phosphorylation of p53 at serine 315 involved in PAI-1 expression was similar with high and low LET radiation, whereas phosphorylation of p53 at serine 37, involved in apoptosis induction, was much higher after high LET irradiation. Conclusions: Our results indicate that diverse mechanisms involved in the development of normal tissue damage may be differentially affected by high and low LET radiation. This may have consequences for the development and manifestation of normal tissue damage.

  10. Monitoring of corrosion damage using high-frequency guided ultrasonic waves

    OpenAIRE

    Chew, D.; Fromme, P.

    2014-01-01

    Due to adverse environmental conditions corrosion can develop during the life cycle of industrial structures, e.g., offshore oil platforms, ships, and desalination plants. Both pitting corrosion and generalized corrosion leading to wall thickness loss can cause the degradation of the integrity and load bearing capacity of the structure. Structural health monitoring of corrosion damage in difficult to access areas can in principle be achieved using high frequency guided waves propagating along...

  11. Design and fabrication of a high-damage threshold infrared Smattt interferometer

    International Nuclear Information System (INIS)

    Hammond, R.B.; Gibbs, A.J.

    1981-01-01

    It has been shown that a Smartt interferometer may be used as a very precise alignment tool for infrared lasers. This interferometer may also be used effectively to investigate the phase front of a laser pulse. To use this tool for applications to high-power, fast-pulse laser systems such as Helios and Antares; however, it has been necessary to fabricate a structure with the unique optical characteristics of the Smartt interferometer combined with a very high optical-damage threshold. We have been successful in this effort by utilizing the high technology, process control, and unique properties of semiconductor-grade, single-crystal Si

  12. Analysis of the damage threshold of the GaAs pseudomorphic high electron mobility transistor induced by the electromagnetic pulse

    International Nuclear Information System (INIS)

    Xi Xiao-Wen; Chai Chang-Chun; Liu Yang; Yang Yin-Tang; Fan Qing-Yang; Shi Chun-Lei

    2016-01-01

    An electromagnetic pulse (EMP)-induced damage model based on the internal damage mechanism of the GaAs pseudomorphic high electron mobility transistor (PHEMT) is established in this paper. With this model, the relationships among the damage power, damage energy, pulse width and signal amplitude are investigated. Simulation results show that the pulse width index from the damage power formula obtained here is higher than that from the empirical formula due to the hotspot transferring in the damage process of the device. It is observed that the damage energy is not a constant, which decreases with the signal amplitude increasing, and then changes little when the signal amplitude reaches up to a certain level. (paper)

  13. CAD/CAM Helps Build Better Bots: High-Tech Design and Manufacture Draws Engineering-Oriented Students

    Science.gov (United States)

    Van Name, Barry

    2012-01-01

    There is a battlefield where no quarter is given, no mercy shown, but not a single drop of blood is spilled. It is an arena that witnesses the bringing together of high-tech design and manufacture with the outpouring of brute force, under the remotely accessed command of some of today's brightest students. This is the world of battling robots, or…

  14. Manufacturing and use of spiral welded pipes for high pressure service : state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Knoop, F.M.; Sommer, B. [Salzgitter GroBrohre GmbH, Salzgitter (Germany)

    2004-07-01

    This paper provided details of an improved helical seam 2-step (HTS) manufacturing process used to produce spiral welded large diameter pipes for high pressure transmission pipelines. During the process, pipe forming is combined with continuous tack welding and internal and external submerged arc welding at separate welding stations. The pipe forming unit consists of a 3 roll bending system with an outside roller cage used to guarantee the roundness of the pipe. The converging strip edges of the pipe are joined using a continuous shielded arc tack weld. Tack welding is done automatically with a laser-guided weld head. Run-out angles are adjusted by an automatic gap control system. The formed and tack-welded pipes are then fed to computer-controlled welding stations for final welding, where each pipe is rotated with a precise screw-like motion. The same welding materials used for the helical seam are used for the skelp end welding. The process offers more precise root gap control, as well as improved pipe geometry. Use of the process has also increased production rates and improved weld stability. The dimensions of the spiral-weld pipes are adjustable so that any diameter can be produced from a base material of the same width. The pipes can also be coated externally with fusion-bonded epoxy or 3-layer polyethylene/polypropylene. It was concluded that the process is being further refined to support the use of HTS pipes in high-pressure pipelines. New nondestructive testing techniques used to assess the performance of the line pipes were presented, as well as the results from hot and cold bending tests, field weldability trials, and tests related to the safety of spiral pipes. 16 refs., 2 tabs., 12 figs.

  15. Design and manufacture of ceramic heat pipes for high temperature applications

    International Nuclear Information System (INIS)

    Meisel, Peter; Jobst, Matthias; Lippmann, Wolfgang; Hurtado, Antonio

    2015-01-01

    Heat exchangers based on ceramic heat pipes were designed for use under highly abrasive and corrosive atmospheres at temperatures in the range of 800–1200 °C for high-temperature power-engineering applications. The presented heat pipes are gravity assisted and based on a multi-layer concept comprising a ceramic cladding and an inner metal tube that contains sodium as the working fluid. Hermetical encapsulation of the working fluid was achieved by electron-beam welding of the inner metal tube. Subsequently, closure of the surrounding ceramic tube was performed by laser brazing technology using a glass solder. Temperature resistance and functionality of the manufactured ceramic thermosyphons could be confirmed experimentally in a hot combustion gas atmosphere at temperatures up to 1100 °C. The ceramic tubes used had an outer diameter of 22 mm and a total length of 770 mm. The measured axial heat transfer of the ceramic gravity assisted heat pipes at the stationary operating point with cold/hot gas temperature of 100 °C/900 °C was 400 W. The result of the calculation using the created mathematical model amounted to 459 W. - Highlights: • Heat-pipe design consists of a ceramic shell and an inner metallic tube. • Laser brazing technology is suitable to seal ceramic heat-pipes. • Thermal characteristic of double wall thermosyphon was modelled using FEM code. • Experimental investigations demonstrated functionality of double wall thermosyphons

  16. Determination of Process Parameters for High-Density, Ti-6Al-4V Parts Using Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-10

    In our earlier work, we described an approach for determining the process parameters that re- sult in high-density parts manufactured using the additive-manufacturing process of selective laser melting (SLM). Our approach, which combines simple simulations and experiments, was demon- strated using 316L stainless steel. We have also used the approach successfully for several other materials. This short note summarizes the results of our work in determining process parameters for Ti-6Al-4V using a Concept Laser M2 system.

  17. 1366 Project Automate: Enabling Automation for <$0.10/W High-Efficiency Kerfless Wafers Manufactured in the US

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Adam [1366 Technologies, Bedford, MA (United States)

    2017-05-10

    For photovoltaic (PV) manufacturing to thrive in the U.S., there must be an innovative core to the technology. Project Automate builds on 1366’s proprietary Direct Wafer® kerfless wafer technology and aims to unlock the cost and efficiency advantages of thin kerfless wafers. Direct Wafer is an innovative, U.S.-friendly (efficient, low-labor content) manufacturing process that addresses the main cost barrier limiting silicon PV cost-reductions – the 35-year-old grand challenge of manufacturing quality wafers (40% of the cost of modules) without the cost and waste of sawing. This simple, scalable process will allow 1366 to manufacture “drop-in” replacement wafers for the $10 billion silicon PV wafer market at 50% of the cost, 60% of the capital, and 30% of the electricity of conventional casting and sawing manufacturing processes. This SolarMat project developed the Direct Wafer processes’ unique capability to tailor the shape of wafers to simultaneously make thinner AND stronger wafers (with lower silicon usage) that enable high-efficiency cell architectures. By producing wafers with a unique target geometry including a thick border (which determines handling characteristics) and thin interior regions (which control light capture and electron transport and therefore determine efficiency), 1366 can simultaneously improve quality and lower cost (using less silicon).

  18. Distress and worry as mediators in the relationship between psychosocial risks and upper body musculoskeletal complaints in highly automated manufacturing.

    Science.gov (United States)

    Wixted, Fiona; Shevlin, Mark; O'Sullivan, Leonard W

    2018-03-15

    As a result of changes in manufacturing including an upward trend in automation and the advent of the fourth industrial revolution, the requirement for supervisory monitoring and consequently, cognitive demand has increased in automated manufacturing. The incidence of musculoskeletal disorders has also increased in the manufacturing sector. A model was developed based on survey data to test if distress and worry mediate the relationship between psychosocial factors (job control, cognitive demand, social isolation and skill discretion), stress states and symptoms of upper body musculoskeletal disorders in highly automated manufacturing companies (n = 235). These constructs facilitated the development of a statistically significant model (RMSEA 0.057, TLI 0.924, CFI 0.935). Cognitive demand was shown to be related to higher distress in employees, and distress to a higher incidence of self-reported shoulder and lower back symptoms. The mediation model incorporating stress states (distress, worry) as mediators is a novel approach in linking psychosocial risks to musculoskeletal disorders. Practitioners' Summary With little requirement for physical work in many modern automated manufacturing workplaces, there is often minimal management focus on Work-Related Musculoskeletal Disorders (WRMSDs) as important occupational health problems. Our model provides evidence that psychosocial factors are important risk factors in symptoms of WRMSD and should be managed.

  19. Monitoring of corrosion damage using high-frequency guided ultrasonic waves

    Science.gov (United States)

    Chew, D.; Fromme, P.

    2015-03-01

    Due to adverse environmental conditions corrosion can develop during the life cycle of industrial structures, e.g., offshore oil platforms, ships, and desalination plants. Both pitting corrosion and generalized corrosion leading to wall thickness loss can cause the degradation of the integrity and load bearing capacity of the structure. Structural health monitoring of corrosion damage in difficult to access areas can in principle be achieved using high frequency guided waves propagating along the structure from accessible areas. Using standard ultrasonic transducers with single sided access to the structure, high frequency guided wave modes were generated that penetrate through the complete thickness of the structure. Wall thickness reduction was induced using accelerated corrosion in a salt water bath. The corrosion damage was monitored based on the effect on the wave propagation and interference of the different modes. The change in the wave interference was quantified based on an analysis in the frequency domain (Fourier transform) and was found to match well with theoretical predictions for the wall thickness loss. High frequency guided waves have the potential for corrosion damage monitoring at critical and difficult to access locations from a stand-off distance.

  20. Progress of High Heat Flux Component Manufacture and Heat Load Experiments in China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.; Lian, Y.; Xu, Z.; Chen, J.; Chen, L.; Wang, Q.; Duan, X., E-mail: xliu@swip.ac.cn [Southwestern Institute of Physics, Chengu (China); Luo, G. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Yan, Q. [University of Science and Technology Beijing, Beijing (China)

    2012-09-15

    Full text: High heat flux components for first wall and divertor are the key subassembly of the present fusion experiment apparatus and fusion reactors in the future. It is requested the metallurgical bonding among the plasma facing materials (PFMs), heat sink and support materials. As to PFMs, ITER grade vacuum hot pressed beryllium CN-G01 was developed in China and has been accepted as the reference material of ITER first wall. Additionally pure tungsten and tungsten alloys, as well as chemical vapor deposition (CVD) W coating are being developed for the aims of ITER divertor application and the demand of domestic fusion devices, and significant progress has been achieved. For plasma facing components (PFCs), high heat flux components used for divertor chamber are being studied according to the development program of the fusion experiment reactor of China. Two reference joining techniques of W/Cu mockups for ITER divertor chamber are being developed, one is mono-block structure by pure copper casting of tungsten surface following by hot iso-static press (HIP), and another is flat structure by brazing. The critical acceptance criteria of high heat flux components are their high heat load performance. A 60 kW Electron-beam Material testing Scenario (EMS-60) has been constructed at Southwestern Institute of Physics (SWIP),which adopts an electron beam welding gun with maximum energy of 150 keV and 150 x 150 mm{sup 2} scanning area by maximum frame rate of 30 kHz. Furthermore, an Engineering Mockup testing Scenario (EMS-400) facility with 400 kW electron-beam melting gun is under construction and will be available by the end of this year. After that, China will have the comprehensive capability of high heat load evaluation from PFMs and small-scale mockups to engineering full scale PFCs. A brazed W/CuCrZr mockup with 25 x 25 x 40 mm{sup 3} in dimension was tested at EMS-60. The heating and cooling time are 10 seconds and 15 seconds, respectively. The experiment

  1. Additive Manufacturing of High-Performance 316L Stainless Steel Nanocomposites via Selective Laser Melting

    Science.gov (United States)

    AlMangour, Bandar Abdulaziz

    Austenitic 316L stainless steel alloy is an attractive industrial material combining outstanding corrosion resistance, ductility, and biocompatibility, with promising structural applications and biomedical uses. However, 316L has low strength and wear resistance, limiting its high-performance applicability. Adding secondary hard nanoscale reinforcements to steel matrices, thereby forming steel-matrix nanocomposites (SMCs), can overcome these problems, improving the performance and thereby the applicability of 316L. However, SMC parts with complex-geometry cannot be easily achieved limiting its application. This can be avoided through additive manufacturing (AM) by generating layer-by-layer deposition using computer-aided design data. Expanding the range of AM-applicable materials is necessary to fulfill industrial demand. This dissertation presents the characteristics of new AM-processed high-performance 316L-matrix nanocomposites with nanoscale TiC or TiB2 reinforcements, addressing specific aspects of material design, process control and optimization, and physical metallurgy theory. The nanocomposites were prepared by high-energy ball-milling and consolidated by AM selective laser melting (SLM). Continuous and refined ring-like network structures were obtained with homogenously distributed reinforcements. Additional grain refinement occurred with reinforcement addition, attributed to nanoparticles acting as nuclei for heterogeneous nucleation. The influence of reinforcement content was first investigated; mechanical and tribological behaviors improved with increased reinforcement contents. The compressive yield strengths of composites with TiB2 or TiC reinforcements were approximately five or two times those of 316L respectively. Hot isostatic pressing post-treatment effectively eliminated major cracks and pores in SLM-fabricated components. The effects of the SLM processing parameters on the microstructure and mechanical performance were also investigated. Laser

  2. New Whole-House Solutions Case Study: Northwest Energy Efficient Manufactured Housing Program High-Performance Test Homes - Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-05-01

    This project represents the third phase of a multi-year effort to develop and bring to market a High Performance Manufactured Home (HPMH). In this project, the Northwest Energy Efficient Manufactured Housing Program worked with Building America Partnership for Improved Residential Construction and Bonneville Power Administration to help four factory homebuilders build prototype zero energy ready manufactured homes, resulting in what is expected to be a 30% savings relative to the Building America Benchmark. (The actual % savings varies depending on choice of heating equipment and climate zone). Previous phases of this project created a HPMH specification and prototyped individual measures from the package to obtain engineering approvals and develop preliminary factory construction processes. This case study describes the project team's work during 2014 to build prototype homes to the HPMH specifications and to monitor the homes for energy performance and durability. Monitoring is expected to continue into 2016.

  3. Automatic Detection of Storm Damages Using High-Altitude Photogrammetric Imaging

    Science.gov (United States)

    Litkey, P.; Nurminen, K.; Honkavaara, E.

    2013-05-01

    The risks of storms that cause damage in forests are increasing due to climate change. Quickly detecting fallen trees, assessing the amount of fallen trees and efficiently collecting them are of great importance for economic and environmental reasons. Visually detecting and delineating storm damage is a laborious and error-prone process; thus, it is important to develop cost-efficient and highly automated methods. Objective of our research project is to investigate and develop a reliable and efficient method for automatic storm damage detection, which is based on airborne imagery that is collected after a storm. The requirements for the method are the before-storm and after-storm surface models. A difference surface is calculated using two DSMs and the locations where significant changes have appeared are automatically detected. In our previous research we used four-year old airborne laser scanning surface model as the before-storm surface. The after-storm DSM was provided from the photogrammetric images using the Next Generation Automatic Terrain Extraction (NGATE) algorithm of Socet Set software. We obtained 100% accuracy in detection of major storm damages. In this investigation we will further evaluate the sensitivity of the storm-damage detection process. We will investigate the potential of national airborne photography, that is collected at no-leaf season, to automatically produce a before-storm DSM using image matching. We will also compare impact of the terrain extraction algorithm to the results. Our results will also promote the potential of national open source data sets in the management of natural disasters.

  4. Damage in agitated vessels of large visco-elastic particles dispersed in a highly viscous fluid.

    Science.gov (United States)

    Bouvier, Laurent; Moreau, Anne; Line, Alain; Fatah, Nouria; Delaplace, Guillaume

    2011-01-01

    Many food recipes entail several homogenization steps for solid particles in hot or cold viscous liquids, such as pureed fruit and sugar, jam or sauce with mushroom pieces. Unfortunately, these unavoidable processes induce damage to the solid particles. To date, little is known of the extent and nature of the damage caused. Consequently, few clear guidelines are available for monitoring solid particle integrity when mixing solid/liquid suspensions in an agitated tank. In this study, an attempt is made to quantify the impact of various physical parameters including the influence of the rotational speed of the impeller and the processing time on particle attrition, when a suspension of large visco-elastic particles in a highly viscous fluid is mixed under isothermal condition. Pectin gel particles were immerged in a viscous liquid and homogenized for various times and rotational speeds, while the evolution of the particle's morphological parameters was monitored. Then, a set of dimensionless numbers governing the attrition mechanism is established and some empirical process relationships are proposed to correlate these numbers to the morphological characteristics and mass balance ratios. From the conditions observed, it is clear that 2 dimensionless ratios could be responsible for a change in the damaging mechanisms. These 2 ratios are the Froude and impeller rotation numbers. Finally, in the conditions tested, mass balance ratios appear to be mainly sensitive to the impeller rotational number, while the shape ratios are both impacted by the Froude and impeller rotational numbers. Damage to solid particles suspended in a stirred vessel reduce the final product quality in industrial cooking processes. Examples of this are fruit in jam or sauces with mushroom pieces. The attrition phenomenon was measured and the influences of the impeller rotational speed and processing time were evaluated quantitatively in function of dimensionless numbers. This study contributes key

  5. Lubricant based determination of design space for continuously manufactured high dose paracetamol tablets.

    Science.gov (United States)

    Taipale-Kovalainen, Krista; Karttunen, Anssi-Pekka; Ketolainen, Jarkko; Korhonen, Ossi

    2018-03-30

    The objective of this study was to devise robust and stable continuous manufacturing process settings, by exploring the design space after an investigation of the lubrication-based parameters influencing the continuous direct compression tableting of high dose paracetamol tablets. Experimental design was used to generate a structured study plan which involved 19 runs. The formulation variables studied were the type of lubricant (magnesium stearate or stearic acid) and its concentration (0.5, 1.0 and 1.5%). Process variables were total production feed rate (5, 10.5 and 16kg/h), mixer speed rpm (500, 850 and 1200rpm), and mixer inlet port for lubricant (A or B). The continuous direct compression tableting line consisted of loss-in-weight feeders, a continuous mixer and a tablet press. The Quality Target Product Profile (QTPP) was defined for the final product, as the flowability of powder blends (2.5s), tablet strength (147N), dissolution in 2.5min (90%) and ejection force (425N). A design space was identified which fulfilled all the requirements of QTPP. The type and concentration of lubricant exerted the greatest influence on the design space. For example, stearic acid increased the tablet strength. Interestingly, the studied process parameters had only a very minor effect on the quality of the final product and the design space. It is concluded that the continuous direct compression tableting process itself is insensitive and can cope with changes in lubrication, whereas formulation parameters exert a major influence on the end product quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Combined effects of displacement damage and high gas content in aluminum

    International Nuclear Information System (INIS)

    Farrell, K.; Houston, J.T.

    1976-01-01

    A solid solution alloy of 2300 at. ppM of 6 Li isotope in aluminum was neutron irradiated at about 0.36 T/sub m/ in high, fast and thermal fluxes producing a damage level of 2 to 3 dpa and simultaneously inducing a gas content of about 2200 at. ppM each of helium and tritium from burnup of 6 Li. The gases significantly increased the nucleation of structural defects but did not change the degree of swelling; cavity concentrations were increased approximately 1000-fold, cavity sizes were decreased approximately 10-fold and there was approximately 10-fold increase in the concentrations of dislocations. Also, large cavities were developed on grain boundaries. The cavities were consistent with their being gas-filled bubbles. The refinement of damage structure by the gases caused a considerable increase in radiation hardening. Bend tests at 77 and 296 0 K revealed severe embrittlement and intergranular fracture. Comparison with data from material irradiated to produce comparable gas levels but relatively little displacement damage indicates that premature intergranular failure is much enhanced by the presence of a defect-hardened matrix. Postirradiation annealing tests showed the cavity and dislocation structures to have high resistance to annealing. Annealing also encouraged the development of a secondary population of large cavities believed to be associated with migration and precipitation of tritium

  7. Upgrading of highly elapsed degradation damage evaluation of structural materials for the light water reactors

    International Nuclear Information System (INIS)

    Katada, Yasuyuki; Matsushima, Shinobu; Sato, Shunji

    1998-01-01

    In this study, for degradation of structural materials in accompanying with highly yearly lapse of the nuclear power plants, it was an aim to elucidate interaction between material degradation and degradation under high hot water environment. And, another aims consisted in intention of expansion protection and recovery evaluation of damage due to laser processing method and so on for welded portion showing extreme material degradation and in preparation of damage region diagram based on the obtained data. In this fiscal year, on interaction between materials and environmental degradation, it was found that as stress corrosion cracking of materials hardened by shot peening shows a resemble shapes of stress-strain curve in CERT and CLRT, shapes of load-time curve were much different. On comparison of the SP material and non-processing material, as peak current showing activity of newly created surface shows no difference, re-passivation of the SP material was found to be too late. And, on recovery evaluation of material degradation damage, as it was found that constant melt depth was essential to evaluate corrosion, a condition preparation aimed for melt depth of more than 1 mm. As only small amount of bubbles were observed at molten metal part on YAG laser processing, it was found that many small bubbles scatter at thermal effect part. (G.K.)

  8. In which metals are high electronic excitations able to create damage?

    International Nuclear Information System (INIS)

    Legrand, P.; Dunlop, A.; Lesueur, D.; Lorenzelli, N.; Morillo, J.; Bouffard, S.

    1992-01-01

    Since a few years a certain number of results have shown that high energy deposition through electronic excitation can lead to damage creation in metallic targets. In order to test which is the right parameter favouring damage creation (high d-electrons density favouring electron-phonon coupling, various electrical conductivities, existence of different displacive phase transformations . . .) chosen metallic targets (Zr, Co, Ti, Ag, Pd, Pt, W, Ni) were irradiated on the french accelerator GANIL in Caen, at cryogenic temperatures with GeV-ions (Pb, O). In situ electrical resistance variation measurements at low temperature were achieved, followed by isochronal annealing of defects and post-X-ray observations at room temperature. This study shows that a very strong enhancement of the damage production occurs only in Zr, Ti and Co which present different allotropic phases and in particular a displacive transformation associated with soft modes in the phonon spectrum. The structure of stage I recovery of all the samples depends on the electronic stopping power

  9. Combined effects of displacement damage and high gas content in aluminum

    International Nuclear Information System (INIS)

    Farrell, K.; Houston, J.T.

    1976-05-01

    A solid solution alloy of 2300 appm of 6 Li isotope in aluminum was neutron irradiated at about 0.36 T/sub m/ in high, fast and thermal fluxes producing a damage level of 2 to 3 dpa and simultaneously inducing a gas content of about 2200 appm each of helium and tritium from burnup of 6 Li. The gases significantly increased the nucleation of structural defects but did not change the degree of swelling; cavity concentrations were increased approximately 1000-fold, cavity sizes were decreased approximately 10-fold and there was approximately 10-fold increase in the concentrations of dislocations. Also, large cavities were developed on grain boundaries. The cavities were consistent with their being gas-filled bubbles. The refinement of damage structure by the gases caused a considerable increase in radiation hardening. Bend tests at 77 and 296 K revealed severe embrittlement and intergranular fracture. Comparison with data from material irradiated to produce comparable gas levels but relatively little displacement damage indicates that premature intergranular failure is much enhanced by the presence of a defect-hardened matrix. Postirradiation annealing tests showed the cavity and dislocation structures to have high resistance to annealing. Annealing also encouraged the development of a secondary population of large cavities believed to be associated with migration and precipitation of tritium

  10. Three dimensional imaging of damage in structural materials using high resolution micro-tomography

    Energy Technology Data Exchange (ETDEWEB)

    Buffiere, J.-Y. [GEMPPM UMR CNRS 5510, INSA Lyon, 20 Av. A. Einstein, 69621 Villeurbanne Cedex (France)]. E-mail: jean-yves.buffiere@insa-lyon.fr; Proudhon, H. [GEMPPM UMR CNRS 5510, INSA Lyon, 20 Av. A. Einstein, 69621 Villeurbanne Cedex (France); Ferrie, E. [GEMPPM UMR CNRS 5510, INSA Lyon, 20 Av. A. Einstein, 69621 Villeurbanne Cedex (France); Ludwig, W. [GEMPPM UMR CNRS 5510, INSA Lyon, 20 Av. A. Einstein, 69621 Villeurbanne Cedex (France); Maire, E. [GEMPPM UMR CNRS 5510, INSA Lyon, 20 Av. A. Einstein, 69621 Villeurbanne Cedex (France); Cloetens, P. [ESRF Grenoble (France)

    2005-08-15

    This paper presents recent results showing the ability of high resolution synchrotron X-ray micro-tomography to image damage initiation and development during mechanical loading of structural metallic materials. First, the initiation, growth and coalescence of porosities in the bulk of two metal matrix composites have been imaged at different stages of a tensile test. Quantitative data on damage development has been obtained and related to the nature of the composite matrix. Second, three dimensional images of fatigue crack have been obtained in situ for two different Al alloys submitted to fretting and/or uniaxial in situ fatigue. The analysis of those images shows the strong interaction of the cracks with the local microstructure and provides unique experimental data for modelling the behaviour of such short cracks.

  11. Three dimensional imaging of damage in structural materials using high resolution micro-tomography

    International Nuclear Information System (INIS)

    Buffiere, J.-Y.; Proudhon, H.; Ferrie, E.; Ludwig, W.; Maire, E.; Cloetens, P.

    2005-01-01

    This paper presents recent results showing the ability of high resolution synchrotron X-ray micro-tomography to image damage initiation and development during mechanical loading of structural metallic materials. First, the initiation, growth and coalescence of porosities in the bulk of two metal matrix composites have been imaged at different stages of a tensile test. Quantitative data on damage development has been obtained and related to the nature of the composite matrix. Second, three dimensional images of fatigue crack have been obtained in situ for two different Al alloys submitted to fretting and/or uniaxial in situ fatigue. The analysis of those images shows the strong interaction of the cracks with the local microstructure and provides unique experimental data for modelling the behaviour of such short cracks

  12. Improvement of the damage threshold of high reflectivity multidielectric coatings 1.06 μM

    International Nuclear Information System (INIS)

    Geenen, B.; Malherbes, A.; Guerain, J.; Boisgard, D.

    1985-01-01

    Development of new high power laser for laser-matter interaction in C.E.A. Limeil requires the realization of H.R. coatings with damage thresholds above 8 J/cm/sup 2/. MATRA's laboratory ''couches minces optiques'' (thin optical layers) production commercial mirrors was around 3.5 J/cm/sup 2/ in 1982. In order to obtain better results the authors decided to improve the control of evaporation parameters such as: vacuum and regulation of oxygen pressure by means of a mass spectrometer; better measurements of evaporation temperature and regulation of evaporation rate; measurement and control of substrate temperature by pyrometric observation; and to automatize the process. These different measurements and controls enable them to establish new processing operations giving better evaporation conditions. The result was an increase of damage threshold from 3.5 J/cm/sup 2/ to 8 J/cm/sup 2/

  13. Designing a highly sensitive Eddy current sensor for evaluating damage on thermal barrier coating

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Min; Kim, Hak Joon; Song, Sung Jin; Seok, Chang Seong; Lee, Yeong Ze [Dept. of Mechanical Engineering, Sungkyunkwan University, Suwon (Korea, Republic of); Lee, Seul Gi [LG Electronics, Seoul (Korea, Republic of)

    2016-06-15

    A thermal barrier coating (TBC) has been widely applied to machine components working under high temperature as a thermal insulator owing to its critical financial and safety benefits to the industry. However, the nondestructive evaluation of TBC damage is not easy since sensing of the microscopic change that occurs on the TBC is required during an evaluation. We designed an eddy current probe for evaluating damage on a TBC based on the finite element method (FEM) and validated its performance through an experiment. An FEM analysis predicted the sensitivity of the probe, showing that impedance change increases as the TBC thermally degrades. In addition, the effect of the magnetic shield concentrating magnetic flux density was also observed. Finally, experimental validation showed good agreement with the simulation result.

  14. High-damage-threshold static laser beam shaping using optically patterned liquid-crystal devices.

    Science.gov (United States)

    Dorrer, C; Wei, S K-H; Leung, P; Vargas, M; Wegman, K; Boulé, J; Zhao, Z; Marshall, K L; Chen, S H

    2011-10-15

    Beam shaping of coherent laser beams is demonstrated using liquid crystal (LC) cells with optically patterned pixels. The twist angle of a nematic LC is locally set to either 0 or 90° by an alignment layer prepared via exposure to polarized UV light. The two distinct pixel types induce either no polarization rotation or a 90° polarization rotation, respectively, on a linearly polarized optical field. An LC device placed between polarizers functions as a binary transmission beam shaper with a highly improved damage threshold compared to metal beam shapers. Using a coumarin-based photoalignment layer, various devices have been fabricated and tested, with a measured single-shot nanosecond damage threshold higher than 30 J/cm2.

  15. Fearfulness and feather damage in laying hens divergently selected for high and low feather pecking

    DEFF Research Database (Denmark)

    Rodenburg, T Bas; de Haas, Elske N; Nielsen, Birte Lindstrøm

    2010-01-01

    Feather pecking (FP) remains a major welfare and economic problem in laying hens. FP has been found to be related to other behavioural characteristics, such as fearfulness. There are indications that fearful birds are more likely to develop FP. Furthermore, FP can lead to increased fearfulness...... in the victims. To investigate further the relationship between FP and fearfulness, feather damage and behavioural fear responses were recorded in three White Leghorn lines of laying hens: a line selected for high FP (HFP line), a line selected for low FP (LFP line) and an unselected control line (10th...... in fear responses between the HFP and LFP lines were not found, neither in the TI-test, nor in the HA or NO test. As expected, birds from the HFP line had considerably more feather damage than birds from the LFP line and birds from the unselected control line were intermediate. Cages that withdrew from...

  16. High aspect ratio micro tool manufacturing for polymer replication using mu EDM of silicon, selective etching and electroforming

    DEFF Research Database (Denmark)

    Tosello, Guido; Bissacco, Giuliano; Tang, Peter Torben

    2008-01-01

    Mass fabrication of polymer micro components with high aspect ratio micro-structures requires high performance micro tools allowing the use of low cost replication processes such as micro injection moulding. In this regard an innovative process chain, based on a combination of micro electrical di...... discharge machining (mu EDM) of a silicon substrate, electroforming and selective etching was used for the manufacturing of a micro tool. The micro tool was employed for polymer replication by means of the injection moulding process....

  17. Evaluation of hybrid polymers for high-precision manufacturing of 3D optical interconnects by two-photon absorption lithography

    Science.gov (United States)

    Schleunitz, A.; Klein, J. J.; Krupp, A.; Stender, B.; Houbertz, R.; Gruetzner, G.

    2017-02-01

    The fabrication of optical interconnects has been widely investigated for the generation of optical circuit boards. Twophoton absorption (TPA) lithography (or high-precision 3D printing) as an innovative production method for direct manufacture of individual 3D photonic structures gains more and more attention when optical polymers are employed. In this regard, we have evaluated novel ORMOCER-based hybrid polymers tailored for the manufacture of optical waveguides by means of high-precision 3D printing. In order to facilitate future industrial implementation, the processability was evaluated and the optical performance of embedded waveguides was assessed. The results illustrate that hybrid polymers are not only viable consumables for industrial manufacture of polymeric micro-optics using generic processes such as UV molding. They also are potential candidates to fabricate optical waveguide systems down to the chip level where TPA-based emerging manufacturing techniques are engaged. Hence, it is shown that hybrid polymers continue to meet the increasing expectations of dynamically growing markets of micro-optics and optical interconnects due to the flexibility of the employed polymer material concept.

  18. All fiber cladding mode stripper with uniform heat distribution and high cladding light loss manufactured by CO2 laser ablation

    Science.gov (United States)

    Jebali, M. A.; Basso, E. T.

    2018-02-01

    Cladding mode strippers are primarily used at the end of a fiber laser cavity to remove high-power excess cladding light without inducing core loss and beam quality degradation. Conventional manufacturing methods of cladding mode strippers include acid etching, abrasive blasting or laser ablation. Manufacturing of cladding mode strippers using laser ablation consist of removing parts of the cladding by fused silica ablation with a controlled penetration and shape. We present and characterize an optimized cladding mode stripper design that increases the cladding light loss with a minimal device length and manufacturing time. This design reduces the localized heat generation by improving the heat distribution along the device. We demonstrate a cladding mode stripper written on a 400um fiber with cladding light loss of 20dB, with less than 0.02dB loss in the core and minimal heating of the fiber and coating. The manufacturing process of the designed component is fully automated and takes less than 3 minutes with a very high throughput yield.

  19. New strategy for the optimal design and manufacture of high performance milling heads

    Directory of Open Access Journals (Sweden)

    Bustillo, A.

    2011-12-01

    Full Text Available High-performance mechanical-transmission heads are one of the most complex, costly and problematic parts of a milling machine, owing to the large amount of piping required for transporting fluids and to the high level of mechanical performance that is required from them. This study proposes a strategy for optimising the design and manufacture of head bodies by using aluminium alloys and by integrating tubular stainless steel inserts in the casting of the head. These tubular inserts that are integrated into the aluminium mass are an alternative to cooling conduits currently made by machine drilling. As demonstrated in the experimental validation of the first prototype, the new method has created a design that retains the same mechanical performance, increases its reliability and reduces the weight of the milling machine’s moving parts.

    Los cabezales de transmisión mecánica de altas prestaciones son una de las partes más complejas, costosas y problemáticas de una maquina fresadora. Esto es debido a la gran cantidad de canalizaciones para la transmisión de fluidos que deben de contener y a las altas prestaciones mecánicas que se les exigen. En este trabajo se presenta una estrategia para optimizar el diseño y la fabricación de los cuerpos de estos cabezales basada en la incorporación de aleaciones de aluminio y la inclusión de insertos tubulares de acero en la propia fundición que conforma el cabezal. Los insertos tubulares sustituyen a los canales de refrigeración realizados actualmente por taladros de mecanizado y quedan integrados en la masa de aluminio. La nueva metodología ha permitido realizar un diseño que mantiene las prestaciones mecánicas, aumenta la fiabilidad y reduce la masa de estos elementos móviles de fresadoras como ha demostrado la validación experimental de un primer prototipo.

  20. A high-throughput cheese manufacturing model for effective cheese starter culture screening

    NARCIS (Netherlands)

    Bachmann, H.; Kruijswijk, Z.; Molenaar, D.; Kleerebezem, M.; Hylckama Vlieg, van J.E.T.

    2009-01-01

    Cheese making is a process in which enzymatic coagulation of milk is followed by protein separation, carbohydrate removal, and an extended bacterial fermentation. The number of variables in this complex process that influence cheese quality is so large that the developments of new manufacturing

  1. Additive manufacturing of magnetic shielding and ultra-high vacuum flange for cold atom sensors.

    Science.gov (United States)

    Vovrosh, Jamie; Voulazeris, Georgios; Petrov, Plamen G; Zou, Ji; Gaber, Youssef; Benn, Laura; Woolger, David; Attallah, Moataz M; Boyer, Vincent; Bongs, Kai; Holynski, Michael

    2018-01-31

    Recent advances in the understanding and control of quantum technologies, such as those based on cold atoms, have resulted in devices with extraordinary metrological performance. To realise this potential outside of a lab environment the size, weight and power consumption need to be reduced. Here we demonstrate the use of laser powder bed fusion, an additive manufacturing technique, as a production technique relevant to the manufacture of quantum sensors. As a demonstration we have constructed two key components using additive manufacturing, namely magnetic shielding and vacuum chambers. The initial prototypes for magnetic shields show shielding factors within a factor of 3 of conventional approaches. The vacuum demonstrator device shows that 3D-printed titanium structures are suitable for use as vacuum chambers, with the test system reaching base pressures of 5 ± 0.5 × 10 -10 mbar. These demonstrations show considerable promise for the use of additive manufacturing for cold atom based quantum technologies, in future enabling improved integrated structures, allowing for the reduction in size, weight and assembly complexity.

  2. High performance poly(etherketoneketone) (PEKK) composite parts fabricated using Big Area Additive Manufacturing (BAAM) processes

    Energy Technology Data Exchange (ETDEWEB)

    Kunc, Vlastimil [ORNL; Kishore, Vidya [ORNL; Chen, Xun [ORNL; Ajinjeru, Christine [ORNL; Duty, Chad [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Hassen, Ahmed A [ORNL

    2016-09-01

    ORNL collaborated with Arkema Inc. to investigate poly(etherketoneketone) (PEKK) and its composites as potential feedstock material for Big Area Additive Manufacturing (BAAM) system. In this work thermal and rheological properties were investigated and characterized in order to identify suitable processing conditions and material flow behavior for BAAM process.

  3. Local damage to Ultra High Performance Concrete structures caused by an impact of aircraft engine missiles

    International Nuclear Information System (INIS)

    Riedel, Werner; Noeldgen, Markus; Strassburger, Elmar; Thoma, Klaus; Fehling, Ekkehard

    2010-01-01

    Research highlights: → Experimental series on UHPC panels subjected to aircraft engine impact. → Improved ballistic limit of fiber reinforced UHPC in comparison to conventional R/C. → Detailed investigation of failure mechanisms of fiber reinforced UHPC panel. - Abstract: The impact of an aircraft engine missile causes high stresses, deformations and a severe local damage to conventional reinforced concrete. As a consequence the design of R/C protective structural elements results in components with rather large dimensions. Fiber reinforced Ultra High Performance Concrete (UHPC) is a concrete based material which combines ultra high strength, high packing density and an improved ductility with a significantly increased energy dissipation capacity due to the addition of fiber reinforcement. With those attributes the material is potentially suitable for improved protective structural elements with a reduced need for material resources. The presented paper reports on an experimental series of scaled aircraft engine impact tests with reinforced UHPC panels. The investigations are focused on the material behavior and the damage intensity in comparison to conventional concrete. The fundamental work of is taken as reference for the evaluation of the results. The impactor model of a Phantom F4 GE-J79 engine developed and validated by Sugano et al. is used as defined in the original work. In order to achieve best comparability, the experimental configuration and method are adapted for the UHPC experiments. With 'penetration', 'scabbing' and 'perforation' all relevant damage modes defined in are investigated so that a full set of results are provided for a representative UHPC structural configuration.

  4. The external costs of low probability-high consequence events: Ex ante damages and lay risks

    International Nuclear Information System (INIS)

    Krupnick, A.J.; Markandya, A.; Nickell, E.

    1994-01-01

    This paper provides an analytical basis for characterizing key differences between two perspectives on how to estimate the expected damages of low probability - high consequence events. One perspective is the conventional method used in the U.S.-EC fuel cycle reports [e.g., ORNL/RFF (1994a,b]. This paper articulates another perspective, using economic theory. The paper makes a strong case for considering this, approach as an alternative, or at least as a complement, to the conventional approach. This alternative approach is an important area for future research. I Interest has been growing worldwide in embedding the external costs of productive activities, particularly the fuel cycles resulting in electricity generation, into prices. In any attempt to internalize these costs, one must take into account explicitly the remote but real possibilities of accidents and the wide gap between lay perceptions and expert assessments of such risks. In our fuel cycle analyses, we estimate damages and benefits' by simply monetizing expected consequences, based on pollution dispersion models, exposure-response functions, and valuation functions. For accidents, such as mining and transportation accidents, natural gas pipeline accidents, and oil barge accidents, we use historical data to estimate the rates of these accidents. For extremely severe accidents--such as severe nuclear reactor accidents and catastrophic oil tanker spills--events are extremely rare and they do not offer a sufficient sample size to estimate their probabilities based on past occurrences. In those cases the conventional approach is to rely on expert judgments about both the probability of the consequences and their magnitude. As an example of standard practice, which we term here an expert expected damage (EED) approach to estimating damages, consider how evacuation costs are estimated in the nuclear fuel cycle report

  5. The external costs of low probability-high consequence events: Ex ante damages and lay risks

    Energy Technology Data Exchange (ETDEWEB)

    Krupnick, A J; Markandya, A; Nickell, E

    1994-07-01

    This paper provides an analytical basis for characterizing key differences between two perspectives on how to estimate the expected damages of low probability - high consequence events. One perspective is the conventional method used in the U.S.-EC fuel cycle reports [e.g., ORNL/RFF (1994a,b]. This paper articulates another perspective, using economic theory. The paper makes a strong case for considering this, approach as an alternative, or at least as a complement, to the conventional approach. This alternative approach is an important area for future research. I Interest has been growing worldwide in embedding the external costs of productive activities, particularly the fuel cycles resulting in electricity generation, into prices. In any attempt to internalize these costs, one must take into account explicitly the remote but real possibilities of accidents and the wide gap between lay perceptions and expert assessments of such risks. In our fuel cycle analyses, we estimate damages and benefits' by simply monetizing expected consequences, based on pollution dispersion models, exposure-response functions, and valuation functions. For accidents, such as mining and transportation accidents, natural gas pipeline accidents, and oil barge accidents, we use historical data to estimate the rates of these accidents. For extremely severe accidents--such as severe nuclear reactor accidents and catastrophic oil tanker spills--events are extremely rare and they do not offer a sufficient sample size to estimate their probabilities based on past occurrences. In those cases the conventional approach is to rely on expert judgments about both the probability of the consequences and their magnitude. As an example of standard practice, which we term here an expert expected damage (EED) approach to estimating damages, consider how evacuation costs are estimated in the nuclear fuel cycle report.

  6. Advances in second generation high temperature superconducting wire manufacturing and R and D at American Superconductor Corporation

    Energy Technology Data Exchange (ETDEWEB)

    Rupich, Martin W; Li Xiaoping; Thieme, Cees; Sathyamurthy, Srivatsan; Fleshler, Steven; Tucker, David; Thompson, Elliot; Schreiber, Jeff; Lynch, Joseph; Buczek, David; DeMoranville, Ken; Inch, James; Cedrone, Paul; Slack, James, E-mail: mrupich@amsc.co [American Superconductor Corporation, 64 Jackson Road, Devens, MA 01434-4020 (United States)

    2010-01-15

    The RABiTS(TM)/MOD-YBCO (rolling assisted biaxially textured substrate/metal-organic deposition of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}) route has been established as a low-cost manufacturing process for producing high performance second generation (2G) wire. American Superconductor Corporation (AMSC) has used this approach to establish a production scale manufacturing line based on a wide-web manufacturing process. This initial production line is currently capable of producing 2G wire in lengths to 500 m with critical currents exceeding 250 A cm{sub width}{sup -1} at 77 K, in the self-field. The wide-web process, combined with slitting and lamination processes, allows customization of the 2G wire width and stabilizer composition to meet application specific wire requirements. The production line is currently supplying 2G wire for multiple cable, fault current limiter and coil applications. Ongoing R and D is focused on the development of thicker YBCO layers and improved flux pinning centers. This paper reviews the history of 2G wire development at AMSC, summarizes the current capability of the 2G wire manufacturing at AMSC, and describes future R and D improvements.

  7. Production of porous sintered materials using wastes of manufacturing engineering in self-propagating high-temperature synthesis

    Directory of Open Access Journals (Sweden)

    Y. S. Povstyana

    2016-06-01

    Full Text Available The increasing amount of wastes produced by the manufacturing engineering, as well as their physical and mechanical properties and restorability provide a search for sphere of their application. The actual problem of modern science is the utilization of wastes and using them in further production that will minimize their harmful impact on the environment and reduce the cost of expensive raw materials. Wastes are ideally suitable for the manufacture of porous permeable materials (filters. Powder metallurgy allows obtaining products with controlled filtration, physical and mechanical properties. Such materials are good filters for regeneration of technical liquids, oils, cooling fluids, sewage etc. The article analyzes the methods and technologies for the manufacture of porous ceramic materials and a new technology for their manufacture, which is based on use of mill scale and natural mineral – saponite as the main components. Compression technology provides products at low pressures and sintering by passing high-temperature synthesis. The proposed technology is characterized by low cost and good physical and mechanical properties of the product that gives a reason to use them for filtering and regeneration of technical liquids.

  8. High resolution transmission electron microscopy and microdiffraction for radiation damage analysis

    International Nuclear Information System (INIS)

    Sinclair, R.

    1982-01-01

    High resolution TEM techniques have developed to quite a sophisticated level over the past few years. In addition TEM instruments with a scanning capability have become available commercially which permit in particular the formation of a small electron probe at the specimen. Thus direct resolution and microdiffraction investigations of thin specimens are now possible, neither of which have been employed to any great extent in the analysis of radiation damage. Some recent advances which are thought to be relevant to this specific area of research are highlighted

  9. Damage process of high purity tungsten coatings by hydrogen beam heat loads

    International Nuclear Information System (INIS)

    Tamura, S.; Tokunaga, K.; Yoshida, N.; Taniguchi, M.; Ezato, K.; Sato, K.; Suzuki, S.; Akiba, M.; Tsunekawa, Y.; Okumiya, M.

    2005-01-01

    To investigate the synergistic effects of heat load and hydrogen irradiation, cyclic heat load tests with a hydrogen beam and a comparable electron beam were performed for high purity CVD-tungsten coatings. Surface modification was examined as a function of the peak temperature by changing the heat flux. Scanning Electron Microscopy analysis showed that the surface damage caused by the hydrogen beam was more severe than that by the electron beam. In the hydrogen beam case, cracking at the surface occurred at all peak temperatures examined from 300 deg. C to 1600 deg. C. These results indicate that the injected hydrogen induces embrittlement for the CVD-tungsten coating

  10. IL-6, Antioxidant Capacity and Muscle Damage Markers Following High-Intensity Interval Training Protocols

    OpenAIRE

    Cipryan, Lukas

    2017-01-01

    Abstract The aim of this study was to investigate changes of interleukin-6 (IL-6), total antioxidant capacity (TAC) and muscle damage markers (creatine kinase (CK), myoglobin and lactate dehydrogenase (LDH)) in response to three different high-intensity interval training (HIIT) protocols of identical external work. Twelve moderately-trained males participated in the three HIIT trials which consisted of a warm-up, followed by 12 min of 15 s, 30 s or 60 s HIIT sequences with the work/rest ratio...

  11. Full-Length High-Temperature Severe Fuel Damage Test No. 5: Final safety analysis

    International Nuclear Information System (INIS)

    Lanning, D.D.; Lombardo, N.J.; Panisko, F.E.

    1993-09-01

    This report presents the final safety analysis for the preparation, conduct, and post-test discharge operation for the Full-Length High Temperature Experiment-5 (FLHT-5) to be conducted in the L-24 position of the National Research Universal (NRU) Reactor at Chalk River Nuclear Laboratories (CRNL), Ontario, Canada. The test is sponsored by an international group organized by the US Nuclear Regulatory Commission. The test is designed and conducted by staff from Pacific Northwest Laboratory with CRNL staff support. The test will study the consequences of loss-of-coolant and the progression of severe fuel damage

  12. STUDY ON THE USAGE OF SPECIAL MATERIALS FOR HIGH-STRENGTH PARTS USED IN THE MACHINES MANUFACTURING INDUSTRY

    Directory of Open Access Journals (Sweden)

    BIBU Marius

    2016-09-01

    Full Text Available Whereas formerly metallic materials were used extensively and for various purposes in the machines manufacturing industry, nowadays new materials are sought that can replace the "conventional" machines manufacturing materials with new ones. This is especially challenging in areas where parts need to be able to withstand very tough conditions, such as high temperatures or large forces applied to them. The current paper intends to analyze some of the most widely used materials for high-strength applications. A special focus in this regard is on the one hand in fiber-reinforced composite materials with the polymer matrix and on the other hand on basalt. The most important properties, processing technologies and applications of these materials are analyzed and discussed and conclusions are drawn regarding their compatibility with the intended purpose.

  13. Fatigue damage assessment of high-usage in-service aircraft fuselage structure

    Science.gov (United States)

    Mosinyi, Bao Rasebolai

    test was terminated. Posttest fractograpic examinations of the crack surfaces were conducted, revealing the presence of subsurface MSD at the critical rivet row of the lap joint. Special attention was also given to the stringer clips that attach the fuselage frames to the stringers, since they also experienced cracking during the fatigue tests. The performance of the different conventional and emerging NDI methods was also assessed, and some of the emerging NDI methods were quite effective in detecting and measuring the length of subsurface cracks. Delta Air Lines conducted a separate destructive investigation on the state of damage along the right-hand side of the fuselage, near stringer 4R. A comparison of these two studies showed that the lap joint on the left hand-side of the aircraft, along stringer 4L, had better fatigue life than the one on the opposite side, along stringer 4R. The cause of the difference in fatigue life was investigated by close examination of the rivet installation qualities, and was found to be a result of better rivet installation along the lap joint at stringer 4L. Finite element models for both the skin and substructures of the panels were developed and geometrically nonlinear finite element analyses were conducted to verify the loading conditions and to determine near-field parameters governing MSD initiation and growth. Fatigue crack growth predictions based on the NASGRO equation were in good agreement with the experimental crack growth data for through-the-thickness cracks. For subsurface cracks, simulation of crack growth was found to correlate better with fractography data when an empirical crack growth model was used. The results of the study contribute to the understanding of the initiation and growth of MSD in the inner skin layer of a lap joint, and provide valuable data for the evaluation and validation of analytical methodologies to predict MSD initiation and growth and a better understanding on the effect of manufacturing

  14. Final Report - Advanced MEA's for Enhanced Operating Conditions, Amenable to High Volume Manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Debe, Mark K.

    2007-09-30

    This report summarizes the work completed under a 3M/DOE contract directed at advancing the key fuel cell (FC) components most critical for overcoming the polymer electrolyte membrane fuel cell (PEMFC) performance, durability & cost barriers. This contract focused on the development of advanced ion exchange membranes & electrocatalysts for PEMFCs that will enable operation under ever more demanding automotive operating conditions & the use high volume compatible processes for their manufacture. Higher performing & more durable electrocatalysts must be developed for PEMFCs to meet the power density & lifetime hours required for FC vehicles. At the same time the amount of expensive Pt catalyst must be reduced to lower the MEA costs. While these two properties are met, the catalyst must be made resistant to multiple degradation mechanisms to reach necessary operating lifetimes. In this report, we present the work focused on the development of a completely new approach to PEMFC electrocatalyts, called nanostructured thin film (NSTF) catalysts. The carbon black supports are eliminated with this new approach which eliminates the carbon corrosion issue. The thin film nature of the catalyst significantly improves its robustness against dissolution & grain growth, preserving the surface area. Also, the activity of the NSTF for oxygen reduction is improved by over 500% compared to dispersed Pt catalyts. Finally, the process for fabricating the NSTF catalysts is consistent with high volume roll-good manufacturing & extremely flexible towards the introduction of new catalyst compositions & structures. This report documents the work done to develop new multi-element NSTF catalysts with properties that exceed pure Pt, that are optimized for use with the membranes discussed below, & advance the state-of-the-art towards meeting the DOE 2010 targets for PEMFC electrocatalysts. The work completed advances the understanding of the NSTF catalyst technology, identifies new NSTF

  15. Fabrication procedures for manufacturing High Flux Isotope Reactor fuel elements - 2

    International Nuclear Information System (INIS)

    Knight, R.W.; Morin, R.A.

    1999-01-01

    The original fabrication procedures written in 1968 delineated the manufacturing procedures at that time. Since 1968, there have been a number of procedural changes. This rewrite of the fabrication procedures incorporates these changes. The entire fuel core of this reactor is made up of two fuel elements. Each element consists of one annular array of fuel plates. These annuli are identified as the inner and outer fuel elements, since one fits inside the other. The inner element consists of 171 identical fuel plates, and the outer element contains 369 identical fuel plates differing slightly from those in the inner element. Both sets of fuel plates contain U 3 O 8 powder as the fuel, dispersed in an aluminum powder matrix and clad with aluminum. Procedures for manufacturing and inspection of the fuel elements are described and illustrated

  16. Fabrication procedures for manufacturing High Flux Isotope Reactor fuel elements - 2

    Energy Technology Data Exchange (ETDEWEB)

    Knight, R.W.; Morin, R.A.

    1999-12-01

    The original fabrication procedures written in 1968 delineated the manufacturing procedures at that time. Since 1968, there have been a number of procedural changes. This rewrite of the fabrication procedures incorporates these changes. The entire fuel core of this reactor is made up of two fuel elements. Each element consists of one annular array of fuel plates. These annuli are identified as the inner and outer fuel elements, since one fits inside the other. The inner element consists of 171 identical fuel plates, and the outer element contains 369 identical fuel plates differing slightly from those in the inner element. Both sets of fuel plates contain U{sub 3}O{sub 8} powder as the fuel, dispersed in an aluminum powder matrix and clad with aluminum. Procedures for manufacturing and inspection of the fuel elements are described and illustrated.

  17. Design and Manufacture of a Highly Reliable, Miniaturized and Low Mass Shutter Mechanism

    Science.gov (United States)

    Manhart, M.; Zeh, T.; Preibler, G.; Hurni, A.; Walter, I.; Helbert, J.; Hiesinger, H.

    2010-01-01

    This paper describes the development, manufacturing and testing of a lightweight shutter mechanism made of titanium for the MERTIS Instrument. MERTIS is a thermal infrared imaging spectrometer onboard ESA's future BepiColombo mission to Mercury. The mechanism is built as a parallelogram arrangement of flexible hinges, actuated by a voice coil. In a first test run, it was shown that the selected EDM processing led to the generation of titanium oxides and an oxygen-enriched surface layer on the substrate (so called alpha-case layer). In the revised version of the shutter, it was possible to manufacture the complex geometry by micro-milling and an adjacent pickling procedure. The adequacy of this approach was verified by lifetime and vibration testing.

  18. Silicon photonics integrated circuits: a manufacturing platform for high density, low power optical I/O's.

    Science.gov (United States)

    Absil, Philippe P; Verheyen, Peter; De Heyn, Peter; Pantouvaki, Marianna; Lepage, Guy; De Coster, Jeroen; Van Campenhout, Joris

    2015-04-06

    Silicon photonics integrated circuits are considered to enable future computing systems with optical input-outputs co-packaged with CMOS chips to circumvent the limitations of electrical interfaces. In this paper we present the recent progress made to enable dense multiplexing by exploiting the integration advantage of silicon photonics integrated circuits. We also discuss the manufacturability of such circuits, a key factor for a wide adoption of this technology.

  19. Low-Cost Nanocellulose-Reinforced High-Temperature Polymer Composites for Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Ozcan, Soydan [ORNL; Tekinalp, Halil L [ORNL; Love, Lonnie J [ORNL; Kunc, Vlastimil [ORNL; Nelson, Kim [American Process Inc.

    2016-07-13

    ORNL worked with American Process Inc. to demonstrate the potential use of bio-based BioPlus® lignin-coated cellulose nanofibrils (L-CNF) as a reinforcing agent in the development of polymer feedstock suitable for additive manufacturing. L-CNF-reinforced polylactic acid (PLA) testing coupons were prepared and up to 69% increase in tensile strength and 133% increase in elastic modulus were demonstrated.

  20. Sectorial and regional determinants of firm dynamics in developing countries: evidence for low, medium and high tech manufacturing in Argentina

    OpenAIRE

    Calá, Carla Daniela

    2018-01-01

    We analyse the determinants of firm dynamics in developing countries using Argentina as an illustrative case. We explain firm entry and exit at the regional level, distinguishing three groups of manufacturing activities: low, medium and high tech. We find that both region -and sector- specific determinants explain firm dynamics, but the impact is not homogeneous across sectors. In particular, for low tech industries, there is a need for explanatory variables that proxy for the specificities o...

  1. Manufacturing Initiative

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Manufacturing Technologies (AMT) Project supports multiple activities within the Administration's National Manufacturing Initiative. A key component of...

  2. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets

    Science.gov (United States)

    Li, Ling; Tirado, Angelica; Nlebedim, I. C.; Rios, Orlando; Post, Brian; Kunc, Vlastimil; Lowden, R. R.; Lara-Curzio, Edgar; Fredette, Robert; Ormerod, John; Lograsso, Thomas A.; Paranthaman, M. Parans

    2016-10-01

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic properties are: intrinsic coercivity Hci = 688.4 kA/m, remanence Br = 0.51 T, and energy product (BH)max = 43.49 kJ/m3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.

  3. Ultra-High Efficiency and Low-Emissions Combustion Technology for Manufacturing Industries

    Energy Technology Data Exchange (ETDEWEB)

    Atreya, Arvind

    2013-04-15

    The purpose of this research was to develop and test a transformational combustion technology for high temperature furnaces to reduce the energy intensity and carbon footprint of U.S. manufacturing industries such as steel, aluminum, glass, metal casting, and petroleum refining. A new technology based on internal and/or external Flue Gas Recirculation (FGR) along with significant enhancement in flame radiation was developed. It produces "Radiative Flameless Combustion (RFC)" and offers tremendous energy efficiency and pollutant reduction benefits over and above the now popular "flameless combustion." It will reduce the energy intensity (or fuel consumption per unit system output) by more than 50% and double the furnace productivity while significantly reducing pollutants and greenhouse gas emissions (10^3 times reduction in NOx and 10 times reduction in CO & hydrocarbons and 3 times reduction in CO2). Product quality improvements are also expected due to uniform radiation, as well as, reduction in scale/dross formation is expected because of non-oxidative atmosphere. RFC is inexpensive, easy to implement, and it was successfully tested in a laboratory-scale furnace at the University of Michigan during the course of this work. A first-ever theory with gas and particulate radiation was also developed. Numerical programs were also written to design an industrial-scale furnace. Nine papers were published (or are in the process of publication). We believe that this early stage research adequately proves the concept through laboratory experiments, modeling and computational models. All this work is presented in the published papers. Important conclusions of this work are: (1) It was proved through experimental measurements that RFC is not only feasible but a very beneficial technology. (2) Theoretical analysis of RFC was done in (a) spatially uniform strain field and (b) a planar momentum jet where the strain rate is neither prescribed nor uniform. Four important non

  4. High Cycle Fatigue Damage Mechanisms of MAR-M 247 Superalloy at High Temperatures

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Miroslav; Horník, Vít; Hutař, Pavel; Hrbáček, K.; Kunz, Ludvík

    2016-01-01

    Roč. 69, č. 2 (2016), s. 393-397 ISSN 0972-2815 R&D Projects: GA TA ČR(CZ) TA04011525; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : High cycle fatigue * S-N curves * Fractography * High temperature * EBSD analysis Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.533, year: 2016

  5. Method for the manufacture of a superconductive Nb3Sn layer on a niobium surface for high frequency applications

    International Nuclear Information System (INIS)

    Martens, H.

    1978-01-01

    A manufacturing method for depositing an Nb 3 Sn layer on a niobium surface for high frequency applications comprising developing a tin vapor atmosphere which also contains a highly volatile tin compound in the gaseous state, and holding the portions of the surface which are to be provided with the Nb 3 Sn layer at a temperature of between 900 0 and 1500 0 C for a predetermined period of time to form the Nb 3 Sn layer permitting niobium surfaces of any shape to be provided with Nb 3 Sn layers of high uniformity and quality

  6. Characterization and damaging law of CFC for high heat flux actively cooled plasma facing components

    Energy Technology Data Exchange (ETDEWEB)

    Chevet, G., E-mail: gaelle.chevet@cea.fr [Association EURATOM-CEA, DSM/IRFM, CEA Cadarache, F-13108 Saint Paul lez Durance (France); Martin, E., E-mail: martin@lcts.u-bordeaux1.fr [LCTS, CNRS UMR 5801, Universite Bordeaux 1, Bordeaux (France); Boscary, J., E-mail: jean.boscary@ipp.mpg.de [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany); Camus, G., E-mail: camus@lcts.u-bordeaux1.fr [LCTS, CNRS UMR 5801, Universite Bordeaux 1, Bordeaux (France); Herb, V., E-mail: herb@lcts.u-bordeaux1.fr [LCTS, CNRS UMR 5801, Universite Bordeaux 1, Bordeaux (France); Schlosser, J., E-mail: jacques.schlosser@cea.fr [Association EURATOM-CEA, DSM/IRFM, CEA Cadarache, F-13108 Saint Paul lez Durance (France); Escourbiac, F., E-mail: frederic.escourbiac@cea.fr [Association EURATOM-CEA, DSM/IRFM, CEA Cadarache, F-13108 Saint Paul lez Durance (France); Missirlian, M., E-mail: marc.missirlian@cea.fr [Association EURATOM-CEA, DSM/IRFM, CEA Cadarache, F-13108 Saint Paul lez Durance (France)

    2011-10-01

    The carbon fiber reinforced carbon composite (CFC) Sepcarb N11 has been used in the Tore Supra (TS) tokamak (Cadarache, France) as armour material for the plasma facing components. For the fabrication of the Wendelstein 7-X (W7-X) divertor (Greifswald, Germany), the NB31 material was chosen. For the fabrication of the ITER divertor, two potential CFC candidates are the NB31 and NB41 materials. In the case of Tore Supra, defects such as microcracks or debonding were found at the interface between CFC tile and copper heat sink. A mechanical characterization of the behaviour of N11 and NB31 was undertaken, allowing the identification of a damage model and finite element calculations both for flat tiles (TS and W7-X) and monoblock (ITER) armours. The mechanical responses of these CFC materials were found almost linear under on-axis tensile tests but highly nonlinear under shear tests or off-axis tensile tests. As a consequence, damage develops within the high shear-stress zones.

  7. Characterization and damaging law of CFC for high heat flux actively cooled plasma facing components

    International Nuclear Information System (INIS)

    Chevet, G.; Martin, E.; Boscary, J.; Camus, G.; Herb, V.; Schlosser, J.; Escourbiac, F.; Missirlian, M.

    2011-01-01

    The carbon fiber reinforced carbon composite (CFC) Sepcarb N11 has been used in the Tore Supra (TS) tokamak (Cadarache, France) as armour material for the plasma facing components. For the fabrication of the Wendelstein 7-X (W7-X) divertor (Greifswald, Germany), the NB31 material was chosen. For the fabrication of the ITER divertor, two potential CFC candidates are the NB31 and NB41 materials. In the case of Tore Supra, defects such as microcracks or debonding were found at the interface between CFC tile and copper heat sink. A mechanical characterization of the behaviour of N11 and NB31 was undertaken, allowing the identification of a damage model and finite element calculations both for flat tiles (TS and W7-X) and monoblock (ITER) armours. The mechanical responses of these CFC materials were found almost linear under on-axis tensile tests but highly nonlinear under shear tests or off-axis tensile tests. As a consequence, damage develops within the high shear-stress zones.

  8. Exploring ultrashort high-energy electron-induced damage in human carcinoma cells

    International Nuclear Information System (INIS)

    Rigaud, O.; Fortunel, N.O.; Vaigot, P.; Cadio, E.; Martin, M.T.; Lundh, O.; Faure, J.; Rechatin, C.; Malka, V.; Gauduel, Y.A.

    2010-01-01

    In conventional cancer therapy or fundamental radiobiology research, the accumulated knowledge on the complex responses of healthy or diseased cells to ionizing radiation is generally obtained with low-dose rates. Under these radiation conditions, the time spent for energy deposition is very long compared with the dynamics of early molecular and cellular responses. The use of ultrashort pulsed radiation would offer new perspectives for exploring the 'black box' aspects of long irradiation profiles and favouring the selective control of early damage in living targets. Several attempts were previously performed using nanosecond or picosecond pulsed irradiations on various mammalian cells and radiosensitive mutants at high dose rate. The effects of single or multi-pulsed radiations on cell populations were generally analyzed in the framework of dose survival curves or characterized by 2D imaging of γ-H2AX foci and no increase in cytotoxicity was shown compared with a delivery at a conventional dose rate. Moreover, when multi-shot irradiations were performed, the overall time needed to obtain an integrated dose of several Grays again overlapped with the multi-scale dynamics of bio-molecular damage-repair sequences and cell signalling steps. Ideally, a single-shot irradiation delivering a well-defined energy profile, via a very short temporal window, would permit the approach of a real-time investigation of early radiation induced molecular damage within the confined spaces of cell compartments. Owing to the potential applications of intense ultrashort laser for radiation therapy, the model of the A431 carcinoma cell line was chosen. An ultrafast single-shot irradiation strategy was carried out with these radio-resistant human skin carcinoma cells, using the capacity of an innovating laser-plasma accelerator to generate quasi mono-energetic femtosecond electron bunches in the MeV domain and to deliver a very high dose rate of 10 13 Gy s -1 per pulse. The alkaline comet

  9. Avoiding thermal striping damage: Experimentally-based design procedures for high-cycle thermal fatigue

    International Nuclear Information System (INIS)

    Betts, C.; Judd, A.M.; Lewis, M.W.J.

    1994-01-01

    In the coolant circuits of a liquid metal cooled reactor (LMR), where there is turbulent mixing of coolant streams at different temperatures, there are temperature fluctuations in the fluid. If an item of the reactor structure is immersed in this fluid it will, because of the good heat transfer from the flowing liquid metal, experience surface temperature fluctuations which will induce dynamic surface strains. It is necessary to design the reactor so that these temperature fluctuations do not, over the life of the plant, cause damage. The purpose of this paper is to describe design procedures to prevent damage of this type. Two such procedures are given, one to prevent the initiation of defects in a nominally defect-free structure or to allow initiation only at the end of the component life, and the other to prevent significant growth of undetectable pre-existing defects of the order of 0.2 to 0.4 mm in depth. Experimental validation of these procedures is described, and the way they can be applied in practice is indicated. To set the scene the paper starts with a brief summary of cases in which damage of this type, or the need to avoid such damage, have had important effects on reactor operation. Structural damage caused by high-cycle thermal fatigue has had a significant adverse influence on the operation of LMRs on several occasions. It is necessary to eliminate the risk of such damage at the design stage. In the absence of detailed knowledge of the temperature history to which it will be subject, an LMR structure can be designed so that, if it is initially free of defects more than 0.1 mm deep, no such defects will be initiated by high-cycle fatigue. This can be done by ensuring that the maximum source temperature difference in the liquid metal is less than a limiting value, which depends on temperature. The limit is very low, however, and likely to be restrictive. This method, by virtue of its safety margin, takes into account pre-existing surface crack

  10. Development toward rapid and efficient screening for high performance hydrolysate lots in a recombinant monoclonal antibody manufacturing process.

    Science.gov (United States)

    Luo, Ying; Pierce, Karisa M

    2012-07-01

    Plant-derived hydrolysates are widely used in mammalian cell culture media to increase yields of recombinant proteins and monoclonal antibodies (mAbs). However, these chemically varied and undefined raw materials can have negative impact on yield and/or product quality in large-scale cell culture processes. Traditional methods that rely on fractionation of hydrolysates yielded little success in improving hydrolysate quality. We took a holistic approach to develop an efficient and reliable method to screen intact soy hydrolysate lots for commercial recombinant mAb manufacturing. Combined high-resolution (1) H nuclear magnetic resonance (NMR) spectroscopy and partial least squares (PLS) analysis led to a prediction model between product titer and NMR fingerprinting of soy hydrolysate with cross-validated correlation coefficient R(2) of 0.87 and root-mean-squared-error of cross-validation RMSECV% of 11.2%. This approach screens for high performance hydrolysate lots, therefore ensuring process consistency and product quality in the mAb manufacturing process. Furthermore, PLS analysis was successful in discerning multiple markers (DL-lactate, soy saccharides, citrate and succinate) among hydrolysate components that positively and negatively correlate with titer. Interestingly, these markers correlate to the metabolic characteristics of some strains of taxonomically diverse lactic acid bacteria (LAB). Thus our findings indicate that LAB strains may exist during hydrolysate manufacturing steps and their biochemical activities may attribute to the titer enhancement effect of soy hydrolysates. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  11. Development and application of high-precision laser welding technology for manufacturing Ti alloy frames of glasses

    International Nuclear Information System (INIS)

    Kim, S. S.; Yang, M. S.; Kim, W. K.; Lee, D. Y.; Kim, J. M.; Leem, B. C.; Shin, J. S.; Lee, D. H.

    1999-12-01

    The research and development efforts of the high precision laser welding technology for manufacturing titanium alloy frames of glasses. For this purpose, laser welding device with the high beam quality is designed and fabricated, which consists of a optical fiber transmission part, a welding monitoring part and a welding controller. The welding nozzle and holding fixtures for manufacturing titanium and shape memory alloy frames of glasses. Titanium and shape memory alloy frames of glasses to be developed were experimentally manufactured by utilizing the laser welding using the optical fiber of GI 400 μm. As a result, the seam welding with the bead width of 0.3 mm or less and the weld penetration of 0.3-0.4mm could be accomplished. The fundamental technology was established through design of welding jigs with a variety of configurations and adequate welding conditions. Also, for the purpose to enable the companies participating in this project to commercialize the developed technology acceleratedly, a training program for the engineers belonging to such companies was conducted along with the technology transfer through joint experiments with the engineers. (author)

  12. High-density plasma etching of III-nitrides: Process development, device applications and damage remediation

    Science.gov (United States)

    Singh, Rajwinder

    Plasma-assisted etching is a key technology for III-nitride device fabrication. The inevitable etch damage resulting from energetic pattern transfer is a challenge that needs to be addressed in order to optimize device performance and reliability. This dissertation focuses on the development of a high-density inductively-coupled plasma (ICP) etch process for III-nitrides, the demonstration of its applicability to practical device fabrication using a custom built ICP reactor, and development of techniques for remediation of etch damage. A chlorine-based standard dry etch process has been developed and utilized in fabrication of a number of electronic and optoelectronic III-nitride devices. Annealing studies carried out at 700°C have yielded the important insight that the annealing time necessary for making good-quality metal contacts to etch processed n-GaN is very short (water, prior to metallization, removes some of the etch damage and is helpful in recovering contact quality. In-situ treatment consisting of a slow ramp-down of rf bias at the end of the etch is found to achieve the same effect as the ex-situ treatment. This insitu technique is significantly advantageous in a large-scale production environment because it eliminates a process step, particularly one involving treatment in hydrochloric acid. ICP equipment customization for scaling up the process to full 2-inch wafer size is described. Results on etching of state of the art 256 x 256 AlGaN focal plane arrays of ultraviolet photodetectors are reported, with excellent etch uniformity over the wafer area.

  13. Thermal damage produced by high-irradiance continuous wave CO2 laser cutting of tissue.

    Science.gov (United States)

    Schomacker, K T; Walsh, J T; Flotte, T J; Deutsch, T F

    1990-01-01

    Thermal damage produced by continuous wave (cw) CO2 laser ablation of tissue in vitro was measured for irradiances ranging from 360 W/cm2 to 740 kW/cm2 in order to investigate the extent to which ablative cooling can limit tissue damage. Damage zones thinner than 100 microns were readily produced using single pulses to cut guinea pig skin as well as bovine cornea, aorta, and myocardium. Multiple pulses can lead to increased damage. However, a systematic decrease in damage with irradiance, predicted theoretically by an evaporation model of ablation, was not observed. The damage-zone thickness was approximately constant around the periphery of the cut, consistent with the existence of a liquid layer which stores heat and leads to tissue damage, and with a model of damage and ablation recently proposed by Zweig et al.

  14. Damage structure of gallium arsenide irradiated in a high-voltage electron microscope

    International Nuclear Information System (INIS)

    Loretto, D.; Loretto, M.H.

    1989-01-01

    Semi-insulating undoped gallium arsenide has been irradiated in a high-voltage electron microscope between room temperature and about 500 0 C for doses of up to 5 x 10 22 electrons cm -2 at 1 MeV. Room-temperature irradiation produces small (less than 5 nm) damage clusters. As the temperature of the irradiation is increased, the size of these clusters increases, until at about 300 0 C a high density of dislocation loops can be resolved. The dislocation loops, 20 nm or less in diameter, which are produced at about 500 0 C have been analysed in a bright field using a two-beam inside-outside method which minimises the tilt necessary between micrographs. It is concluded that the loops are an interstitial perfect-edge type with a Burgers vector of (a/2) . (author)

  15. Radiation-damage studies, irradiations and high-dose dosimetry for LHC detectors

    CERN Document Server

    Coninckx, F; León-Florián, E; Leutz, H; Schönbacher, Helmut; Sonderegger, P; Tavlet, Marc; Sopko, B; Henschel, H; Schmidt, H U; Boden, A; Bräunig, D; Wulf, F; Cramariuc, R; Ilie, D; Fattibene, P; Onori, S; Miljanic, S; Paic, G; Razen, B; Razem, D; Rendic, D; CERN. Geneva. Detector Research and Development Committee

    1991-01-01

    The proposal is divided into a main project and special projects. The main project consists of a service similar to the one given in the past to accelerator construction projects at CERN (ISR,SPS,LEP) on high-dose dosimetry, material irradiations, irradiations tests, standardization of test procedures and data compilations. Large experience in this field and numerous radiation damage test data of insulating and structural materials are available. The special projects cover three topics which are of specific interest for LHC detector physicists and engineers at CERN and in other high energy physics institutes, namely: Radiation effects in scintillators; Selection of radiation hard optical fibres for data transmission; and Selection and testing of radiation hard electronic components.

  16. Which markers of subclinical organ damage to measure in individuals with high normal blood pressure?

    DEFF Research Database (Denmark)

    Sehestedt, Thomas; Jeppesen, Jørgen; Hansen, Tine W

    2009-01-01

    plaques or urine albumin/creatinine ratio of at least the 90th percentile did not produce significantly worse results. Seventy-five percent of individuals with three or more traditional risk factors had SOD. CONCLUSION: In healthy individuals with high normal BP, measuring two of pulse wave velocities......OBJECTIVE: Medical treatment of healthy individuals with high normal blood pressure (BP) is recommended if there is subclinical organ damage (SOD). We examined which markers of SOD to use based on their supplementary prognostic value. METHODS: In a population sample of 1968 individuals, aged 41, 51......, 61 and 71 years, without diabetes, prior stroke or myocardial infarction, not receiving any cardiovascular, antidiabetic or lipid-lowering medications, we measured urine albumin/creatinine ratio, carotid atherosclerotic plaques, carotid/femoral pulse wave velocity and left ventricular mass index...

  17. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets.

    Science.gov (United States)

    Li, Ling; Tirado, Angelica; Nlebedim, I C; Rios, Orlando; Post, Brian; Kunc, Vlastimil; Lowden, R R; Lara-Curzio, Edgar; Fredette, Robert; Ormerod, John; Lograsso, Thomas A; Paranthaman, M Parans

    2016-10-31

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm 3 , and the room temperature magnetic properties are: intrinsic coercivity H ci  = 688.4 kA/m, remanence B r  = 0.51 T, and energy product (BH) max  = 43.49 kJ/m 3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.

  18. Role of interfaces i nthe design of ultra-high strength, radiation damage tolerant nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Nastasi, Michael A [Los Alamos National Laboratory; Baldwin, Jon K [Los Alamos National Laboratory; Wei, Qiangmin [Los Alamos National Laboratory; Li, Nan [Los Alamos National Laboratory; Mara, Nathan [Los Alamos National Laboratory; Zhang, Xinghang [Los Alamos National Laboratory; Fu, Engang [Los Alamos National Laboratory; Anderoglu, Osman [Los Alamos National Laboratory; Li, Hongqi [Los Alamos National Laboratory; Bhattacharyya, Dhriti [NON LANL

    2010-12-09

    The combination of high strength and high radiation damage tolerance in nanolaminate composites can be achieved when the individual layers in these composites are only a few nanometers thick and contain special interfaces that act both as obstacles to slip, as well as sinks for radiation-induced defects. The morphological and phase stabilities and strength and ductility of these nano-composites under ion irradiation are explored as a function of layer thickness, temperature and interface structure. Magnetron sputtered metallic multilayers such as Cu-Nb and V-Ag with a range of individual layer thickness from approximately 2 nm to 50 nm and the corresponding 1000 nm thick single layer films were implanted with helium ions at room temperature. Cross-sectional Transmission Electron Microscopy (TEM) was used to measure the distribution of helium bubbles and correlated with the helium concentration profile measured vis ion beam analysis techniques to obtain the helium concentration at which bubbles are detected in TEM. It was found that in multilayers the minimum helium concentration to form bubbles (approximately I nm in size) that are easily resolved in through-focus TEM imaging was several atomic %, orders of magnitude higher than that in single layer metal films. This observation is consistent with an increased solubility of helium at interfaces that is predicted by atomistic modeling of the atomic structures of fcc-bcc interfaces. At helium concentrations as high as 7 at.%, a uniform distribution of I nm diameter bubbles results in negligible irradiation hardening and loss of deformability in multi layers with layer thicknesses of a few nanometers. The control of atomic structures of interfaces to produce high helium solubility at interfaces is crucial in the design of nano-composite materials that are radiation damage tolerant. Reduced radiation damage also leads to a reduction in the irradiation hardening, particularly at layer thickness of approximately 5 run

  19. Impact Damage Evaluation Method of Friction Disc Based on High-Speed Photography and Tooth-Root Stress Coupling

    International Nuclear Information System (INIS)

    Yin, L; Shao, Y M; Liu, J; Zheng, H L

    2015-01-01

    The stability of friction disc could be seriously affected by the tooth surface damage due to poor working conditions of the wet multi-disc brake in heavy trucks. There are few current works focused on the damage of the friction disc caused by torsion-vibration impacts. Hence, it is necessary to investigate its damage mechanisms and evaluation methods. In this paper, a damage mechanism description and evaluation method of a friction disc based on the high-speed photography and tooth-root stress coupling is proposed. According to the HighSpeed Photography, the collision process between the friction disc and hub is recorded, which can be used to determine the contact position and deformation. Combined with the strain-stress data obtained by the strain gauge at the place of the tooth-root, the impact force and property are studied. In order to obtain the evaluation method, the damage surface morphology data of the friction disc extracted by 3D Super Depth Digital Microscope (VH-Z100R) is compared with the impact force and property. The quantitative relationships between the amount of deformation and collision number are obtained using a fitting analysis method. The experimental results show that the damage of the friction disc can be evaluated by the proposed impact damage evaluation method based on the high-speed photography and tooth-root stress coupling. (paper)

  20. Relationships between browsing damage and the species dominance by the highly food-attractive and less food-attractive trees

    Directory of Open Access Journals (Sweden)

    Petr Čermák

    2011-01-01

    Full Text Available The paper analyses data on the browsing damage to Acer pseudoplatanus, Carpinus betulus, Fraxinus excelsior, Quercus spp., Tilia cordata and Fagus sylvatica. Field research was carried out in the period 2007–2010 and analysed data came from 33 transects at 10 localities with the various abundance of game in the CR (everywhere Capreolus capreolus, on several plots also Cervus elaphus, Ovis musimon or Dama dama. Trees were monitored up to a height of 150 cm in natural regeneration under stands and in plantations and the occurrence was noted of new browsing damage. Differences between the percentage of damaged individuals of the given species of a food-attractive species (A. p., C. b., F. e. and the percentage of damaged individuals of all tree species on a transect as well as the proportion of these parameters correlate negatively with the given species dominance and thus, they appear to be suitable parameters for the analysis of relationships between the damage intensity and dominance. The higher the percentage proportions of highly food-attractive species and the lower the percentage of less-attractive species, the lower the relative intensity of damage to highly food-attractive species. At the same time, the higher the percentage proportion of highly food-attractive species and the lower the percentage of less-attractive species then the lower a difference between damage to less food-attractive species and all species.

  1. Vochysia rufa Stem Bark Extract Protects Endothelial Cells against High Glucose Damage

    Directory of Open Access Journals (Sweden)

    Neire Moura de Gouveia

    2017-02-01

    Full Text Available Background: Increased oxidative stress by persistent hyperglycemia is a widely accepted factor in vascular damage responsible for type 2 diabetes complications. The plant Vochysia rufa (Vr has been used in folk medicine in Brazil for the treatment of diabetes. Thus; the protective effect of a Vr stem bark extract against a challenge by a high glucose concentration on EA.hy926 (EA endothelial cells is evaluated. Methods: Vegetal material is extracted with distilled water by maceration and evaporated until dryness under vacuum. Then; it is isolated by capillary electrophoresis–tandem mass spectrometry. Cell viability is evaluated on EA cells treated with 0.5–100 µg/mL of the Vr extract for 24 h. The extract is diluted at concentrations of 5, 10 and 25 µg/mL and maintained for 24 h along with 30 mM of glucose to evaluate its protective effect on reduced glutathione (GSH; glutathione peroxidase (GPx and reductase (GR and protein carbonyl groups. Results: V. rufa stem bark is composed mainly of sugars; such as inositol; galactose; glucose; mannose; sacarose; arabinose and ribose. Treatment with Vr up to 100 µg/mL for 24 h did not affect cell viability. Treatment of EA cells with 30 mM of glucose for 24 h significantly increased the cell damage. EA cells treated with 30 mM of glucose showed a decrease of GSH concentration and increased Radical Oxygen Species (ROS and activity of antioxidant enzymes and protein carbonyl levels; compared to control. Co-treatment of EA with 30 mM glucose plus 1–10 μg/mL Vr significantly reduced cell damage while 5–25 μg/mL Vr evoked a significant protection against the glucose insult; recovering ROS; GSH; antioxidant enzymes and carbonyls to baseline levels. Conclusion: V. rufa extract protects endothelial cells against oxidative damage by modulating ROS; GSH concentration; antioxidant enzyme activity and protein carbonyl levels.

  2. Experimental investigation and analysis of damage evolution in concrete under high-cyclic fatigue loadings

    International Nuclear Information System (INIS)

    Thiele, Marc

    2016-01-01

    The main objective of this thesis is the fatigue behavior of concrete under high-cycle compressive loadings. Current knowledge about fatigue behavior of concrete is still incomplete. This concerns especially the process of fatigue which is preceding the fatigue failure. The leak of knowledge about fatigue behavior is opposed to the steady growing importance of this topic within the practice in civil engineering. Therefore, within this thesis a systematic and comprehensive investigation of the process of fatigue itself was done. This contributes to the better understanding of the progression of damage and the corresponding processes within the material. The experimental investigation consisted mainly of experiments with constant amplitude loadings in compression with cylindrical specimen made of normal strength concrete. Two differed load levels were used which resulted in numbers of cycles to failure of 10 6 and 10 7 as well as 10 3 and 10 4 . The experiments were done in combination with different types of nondestructive and destructive testing methods like strain measuring, deformation of surface, ultrasonic signals, acoustic emissions, optical microscopy and also scattering electron microscopy. To access some parameters of influence in relation to the fatigue behavior additional creep tests and also several tests with different scales of specimen were done. The fatigue process of concrete is determined as an evolution of damage that starts from the beginning of the loading process. This evolution has manifold and different influences on the different material properties of concrete. In this relation a major finding was that fatigue related damage leads to a transformation of the complete stress-strain-relationship. This relationship is also subjected to an evolution process. Due to the authors observations it could not be determined that the investigated changes in macroscopic material behavior are caused by a development of micro cracks within the material

  3. High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise

    Science.gov (United States)

    Macgregor, Lewis J.

    2018-01-01

    Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; pmotor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures. PMID:29630622

  4. Full-length high-temperature severe fuel damage test No. 5

    International Nuclear Information System (INIS)

    Lanning, D.D.; Lombardo, N.J.; Hensley, W.K.; Fitzsimmons, D.E.; Panisko, F.E.; Hartwell, J.K.

    1993-09-01

    This report describes and presents data from a severe fuel damage test that was conducted in the National Research Universal (NRU) reactor at Chalk River Nuclear Laboratories (CRNL), Ontario, Canada. The test, designated FLHT-5, was the fourth in a series of full-length high-temperature (FLHT) tests on light-water reactor fuel. The tests were designed and performed by staff from the US Department of Energy's Pacific Northwest Laboratory (PNL), operated by Battelle Memorial Institute. The test operation and test results are described in this report. The fuel bundle in the FLHT-5 experiment included 10 unirradiated full-length pressurized-water reactor (PWR) rods, 1 irradiated PWR rod and 1 dummy gamma thermometer. The fuel rods were subjected to a very low coolant flow while operating at low fission power. This caused coolant boilaway, rod dryout and overheating to temperatures above 2600 K, severe fuel rod damage, hydrogen generation, and fission product release. The test assembly and its effluent path were extensively instrumented to record temperatures, pressures, flow rates, hydrogen evolution, and fission product release during the boilaway/heatup transient. Post-test gamma scanning of the upper plenum indicated significant iodine and cesium release and deposition. Both stack gas activity and on-line gamma spectrometer data indicated significant (∼50%) release of noble fission gases. Post-test visual examination of one side of the fuel bundle revealed no massive relocation and flow blockage; however, rundown of molten cladding was evident

  5. Rotator Interval Lesion and Damaged Subscapularis Tendon Repair in a High School Baseball Player

    Directory of Open Access Journals (Sweden)

    Tomoyuki Muto

    2015-01-01

    Full Text Available In 2013, a 16-year-old baseball pitcher visited Nobuhara Hospital complaining of shoulder pain and limited range of motion in his throwing shoulder. High signal intensity in the rotator interval (RI area (ball sign, injured subscapularis tendon, and damage to both the superior and middle glenohumeral ligaments were identified using magnetic resonance imaging (MRI. Repair of the RI lesion and partially damaged subscapularis tendon was performed in this pitcher. During surgery, an opened RI and dropping of the subscapularis tendon were observed. The RI was closed in a 90° externally rotated and abducted position. To reconfirm the exact repaired state of the patient, arthroscopic examination was performed from behind. However, suture points were not visible in the >30° externally rotated position, which indicates that the RI could not be correctly repaired with the arthroscopic procedure. One year after surgery, the patient obtained full function of the shoulder and returned to play at a national convention. Surgical repair of the RI lesion should be performed in exactly the correct position of the upper extremity.

  6. Quantification of high-power ultrasound induced damage on potato starch granules using light microscopy.

    Science.gov (United States)

    Zuo, Yue Yue J; Hébraud, Pascal; Hemar, Yacine; Ashokkumar, Muthupandian

    2012-05-01

    A simple light microscopic technique was developed in order to quantify the damage inflicted by high-power low-frequency ultrasound (0-160 W, 20 kHz) treatment on potato starch granules in aqueous dispersions. The surface properties of the starch granules were modified using ethanol and SDS washing methods, which are known to displace proteins and lipids from the surface of the starch granules. The study showed that in the case of normal and ethanol-washed potato starch dispersions, two linear regions were observed. The number of defects first increased linearly with an increase in ultrasound power up to a threshold level. This was then followed by another linear dependence of the number of defects on the ultrasound power. The power threshold where the change-over occurred was higher for the ethanol-washed potato dispersions compared to non-washed potato dispersions. In the case of SDS-washed potato starch, although the increase in defects was linear with the ultrasound power, the power threshold for a second linear region was not observed. These results are discussed in terms of the different possible mechanisms of cavitation induced-damage (hydrodynamic shear stresses and micro-jetting) and by taking into account the hydrophobicity of the starch granule surface. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. A facile approach to manufacturing non-ionic surfactant nanodipsersions using proniosome technology and high-pressure homogenization.

    Science.gov (United States)

    Najlah, Mohammad; Hidayat, Kanar; Omer, Huner K; Mwesigwa, Enosh; Ahmed, Waqar; AlObaidy, Kais G; Phoenix, David A; Elhissi, Abdelbary

    2015-03-01

    In this study, a niosome nanodispersion was manufactured using high-pressure homogenization following the hydration of proniosomes. Using beclometasone dipropionate (BDP) as a model drug, the characteristics of the homogenized niosomes were compared with vesicles prepared via the conventional approach of probe-sonication. Particle size, zeta potential, and the drug entrapment efficiency were similar for both size reduction mechanisms. However, high-pressure homogenization was much more efficient than sonication in terms of homogenization output rate, avoidance of sample contamination, offering a greater potential for a large-scale manufacturing of noisome nanodispersions. For example, high-pressure homogenization was capable of producing small size niosomes (209 nm) using a short single-step of size reduction (6 min) as compared with the time-consuming process of sonication (237 nm in >18 min) and the BDP entrapment efficiency was 29.65% ± 4.04 and 36.4% ± 2.8. In addition, for homogenization, the output rate of the high-pressure homogenization was 10 ml/min compared with 0.83 ml/min using the sonication protocol. In conclusion, a facile, applicable, and highly efficient approach for preparing niosome nanodispersions has been established using proniosome technology and high-pressure homogenization.

  8. Social manufacturing

    OpenAIRE

    Hamalainen, Markko; Karjalainen, Jesse

    2017-01-01

    New business models harnessing the power of individuals have already revolutionized service industries and digital content production. In this study, we investigate whether a similar phenomenon is taking place in manufacturing industries. We start by conceptually defining two distinct forms of firm-individual collaboration in manufacturing industries: (1) social cloud manufacturing, in which firms outsource manufacturing to individuals, and (2) social platform manufacturing, in which firms pr...

  9. Highly active, recyclable catalyst for the manufacture of viscous, low molecular weight, CO–ethene–propene-based polyketone, base component for a new class of resins

    NARCIS (Netherlands)

    Broekhuis, Antonius A.; Dirkzwager, Hendrik; Mul, Wilhelmus P.; Heeres, Hero J.; Linden, Adrianus J. van der; Orpen, A. Guy

    2002-01-01

    A highly active, recyclable homogeneous palladium(II) catalyst is described for the manufacture of viscous, low molecular weight CO–ethene–propene-based polyketone (Carilite Oligomer), used for the manufacture of a new class of resins (Carilite Resins). The catalyst is composed of palladium acetate,

  10. Skin damage probabilities using fixation materials in high-energy photon beams

    International Nuclear Information System (INIS)

    Carl, J.; Vestergaard, A.

    2000-01-01

    Patient fixation, such as thermoplastic masks, carbon-fibre support plates and polystyrene bead vacuum cradles, is used to reproduce patient positioning in radiotherapy. Consequently low-density materials may be introduced in high-energy photon beams. The aim of the this study was to measure the increase in skin dose when low-density materials are present and calculate the radiobiological consequences in terms of probabilities of early and late skin damage. An experimental thin-windowed plane-parallel ion chamber was used. Skin doses were measured using various overlaying low-density fixation materials. A fixed geometry of a 10 x 10 cm field, a SSD = 100 cm and photon energies of 4, 6 and 10 MV on Varian Clinac 2100C accelerators were used for all measurements. Radiobiological consequences of introducing these materials into the high-energy photon beams were evaluated in terms of early and late damage of the skin based on the measured surface doses and the LQ-model. The experimental ion chamber save results consistent with other studies. A relationship between skin dose and material thickness in mg/cm 2 was established and used to calculate skin doses in scenarios assuming radiotherapy treatment with opposed fields. Conventional radiotherapy may apply mid-point doses up to 60-66 Gy in daily 2-Gy fractions opposed fields. Using thermoplastic fixation and high-energy photons as low as 4 MV do increase the dose to the skin considerably. However, using thermoplastic materials with thickness less than 100 mg/cm 2 skin doses are comparable with those produced by variation in source to skin distance, field size or blocking trays within clinical treatment set-ups. The use of polystyrene cradles and carbon-fibre materials with thickness less than 100 mg/cm 2 should be avoided at 4 MV at doses above 54-60 Gy. (author)

  11. Statistical damage analysis of transverse cracking in high temperature composite laminates

    International Nuclear Information System (INIS)

    Sun Zuo; Daniel, I.M.; Luo, J.J.

    2003-01-01

    High temperature polymer composites are receiving special attention because of their potential applications to high speed transport airframe structures and aircraft engine components exposed to elevated temperatures. In this study, a statistical analysis was used to study the progressive transverse cracking in a typical high temperature composite. The mechanical properties of this unidirectional laminate were first characterized both at room and high temperatures. Damage mechanisms of transverse cracking in cross-ply laminates were studied by X-ray radiography at room temperature and in-test photography technique at high temperature. Since the tensile strength of unidirectional laminate along transverse direction was found to follow Weibull distribution, Monte Carlo simulation technique based on experimentally obtained parameters was applied to predict transverse cracking at different temperatures. Experiments and simulation showed that they agree well both at room temperature and 149 deg. C (stress free temperature) in terms of applied stress versus crack density. The probability density function (PDF) of transverse crack spacing considering statistical strength distribution was also developed, and good agreements with simulation and experimental results are reached. Finally, a generalized master curve that predicts the normalized applied stress versus normalized crack density for various lay-ups and various temperatures was established

  12. Design, manufacture and spin test of high contact ratio helicopter transmission utilizing Self-Aligning Bearingless Planetary (SABP)

    Science.gov (United States)

    Folenta, Dezi; Lebo, William

    1988-01-01

    A 450 hp high ratio Self-Aligning Bearingless Planetary (SABP) for a helicopter application was designed, manufactured, and spin tested under NASA contract NAS3-24539. The objective of the program was to conduct research and development work on a high contact ratio helical gear SABP to reduce weight and noise and to improve efficiency. The results accomplished include the design, manufacturing, and no-load spin testing of two prototype helicopter transmissions, rated at 450 hp with an input speed of 35,000 rpm and an output speed of 350 rpm. The weight power density ratio of these gear units is 0.33 lb hp. The measured airborne noise at 35,000 rpm input speed and light load is 94 dB at 5 ft. The high speed, high contact ratio SABP transmission appears to be significantly lighter and quieter than comtemporary helicopter transmissions. The concept of the SABP is applicable not only to high ratio helicopter type transmissions but also to other rotorcraft and aircraft propulsion systems.

  13. CONWIP versus POLCA: A comparative analysis in a high-mix, low-volume (HMLV) manufacturing environment

    Energy Technology Data Exchange (ETDEWEB)

    Frazee, T.; Standridge, C.

    2016-07-01

    Few studies comparing manufacturing control systems as they relate to high-mix, low-volume applications have been reported. This paper compares two strategies, constant work in process (CONWIP) and Paired-cell Overlapping Loops of Cards with Authorization (POLCA), for controlling work in process (WIP) in such a manufacturing environment. Characteristics of each control method are explained in regards to lead time impact and thus, why one may be advantageous over the other. An industrial system in the Photonics industry is studied. Discrete event simulation is used as the primary tool to compare performance of CONWIP and POLCA controls for the same WIP level with respect to lead time. Model verification and validation are accomplished by comparing historic data to simulation generated data including utilizations. Both deterministic and Poisson distributed order arrivals are considered. For the system considered in this case study, including order arrival patterns, a POLCA control can outperform a CONWIP parameter in terms of average lead time for a given level of WIP. At higher levels of WIP, the performance of POLCA and CONWIP is equivalent. The POLCA control helps limit WIP in specific áreas of the system where the CONWIP control only limits the overall WIP in the system. Thus, POLCA can generate acceptably low lead times at lower levels of WIP for conditions equivalent to the HMLV manufacturing systems studied. The study compliments and extends previous studies of CONWIP and POLCA performance to a HMLV manufacturing environment. It demonstrates the utility of discrete event simulation in that regard. It shows that proper inventory controls in bottleneck áreas of a system can reduce average lead time. (Author)

  14. Stress and Damage in Polymer Matrix Composite Materials Due to Material Degradation at High Temperatures

    Science.gov (United States)

    McManus, Hugh L.; Chamis, Christos C.

    1996-01-01

    This report describes analytical methods for calculating stresses and damage caused by degradation of the matrix constituent in polymer matrix composite materials. Laminate geometry, material properties, and matrix degradation states are specified as functions of position and time. Matrix shrinkage and property changes are modeled as functions of the degradation states. The model is incorporated into an existing composite mechanics computer code. Stresses, strains, and deformations at the laminate, ply, and micro levels are calculated, and from these calculations it is determined if there is failure of any kind. The rationale for the model (based on published experimental work) is presented, its integration into the laminate analysis code is outlined, and example results are given, with comparisons to existing material and structural data. The mechanisms behind the changes in properties and in surface cracking during long-term aging of polyimide matrix composites are clarified. High-temperature-material test methods are also evaluated.

  15. Simulation of electron displacement damage in a high voltage electron microscope

    International Nuclear Information System (INIS)

    Ono, Susumu; Kanaya, Koichi

    1979-01-01

    By applying the fundamental theory of the neutron cooling to the conservation law of energy and momentum, the threshold energies of incident electrons for displacing atoms are calculated and illustrated periodically for the atomic number. And the observable damage due to the secondary action of displaced atoms in the practical use of a high voltage electron microscope is described for several materials and accelerating voltages. The trajectories of incident electrons and displaced atoms in several materials are simulated by a Monte-Carlo method, using rigorous formulas of electron scattering events, i.e. elastic and inelastic scattering cross-sections, ionization loss and plasmon excitation. The simulation results are substantially agreement with experiments. (author)

  16. Radiation damage and thermal shock response of carbon-fiber-reinforced materials to intense high-energy proton beams

    Directory of Open Access Journals (Sweden)

    N. Simos

    2016-11-01

    Full Text Available A comprehensive study on the effects of energetic protons on carbon-fiber composites and compounds under consideration for use as low-Z pion production targets in future high-power accelerators and low-impedance collimating elements for intercepting TeV-level protons at the Large Hadron Collider has been undertaken addressing two key areas, namely, thermal shock absorption and resistance to irradiation damage. Carbon-fiber composites of various fiber weaves have been widely used in aerospace industries due to their unique combination of high temperature stability, low density, and high strength. The performance of carbon-carbon composites and compounds under intense proton beams and long-term irradiation have been studied in a series of experiments and compared with the performance of graphite. The 24-GeV proton beam experiments confirmed the inherent ability of a 3D C/C fiber composite to withstand a thermal shock. A series of irradiation damage campaigns explored the response of different C/C structures as a function of the proton fluence and irradiating environment. Radiolytic oxidation resulting from the interaction of oxygen molecules, the result of beam-induced radiolysis encountered during some of the irradiation campaigns, with carbon atoms during irradiation with the presence of a water coolant emerged as a dominant contributor to the observed structural integrity loss at proton fluences ≥5×10^{20}  p/cm^{2}. The carbon-fiber composites were shown to exhibit significant anisotropy in their dimensional stability driven by the fiber weave and the microstructural behavior of the fiber and carbon matrix accompanied by the presence of manufacturing porosity and defects. Carbon-fiber-reinforced molybdenum-graphite compounds (MoGRCF selected for their impedance properties in the Large Hadron Collider beam collimation exhibited significant decrease in postirradiation load-displacement behavior even after low dose levels (∼5×10^{18}

  17. Innovative manufacturing technologies for low-cost, high efficiency PERC-based PV modules

    Energy Technology Data Exchange (ETDEWEB)

    Yelundur, Vijay [Suniva Inc., Norcross, GA (United States)

    2017-04-19

    The goal this project was to accelerate the deployment of innovative solar cell and module technologies that reduce the cost of PERC-based modules to best-in-class. New module integration technology was to be used to reduce the cost and reliance on conventional silver bus bar pastes and enhance cell efficiency. On the cell manufacturing front, the cost of PERC solar cells was to be reduced by introducing advanced metallization approaches to increase cell efficiency. These advancements will be combined with process optimization to target cell efficiencies in the range of 21 to 21.5%. This project will also explore the viability of a bifacial PERC solar cell design to enable cost savings through the use of thin silicon wafers. This project was terminated on 4/30/17 after four months of activity due financial challenges facing the recipient.

  18. Rapid die manufacturing - high pressure casting of low volume non ferrous metals components

    CSIR Research Space (South Africa)

    Pereira, MFV

    2006-11-01

    Full Text Available .csir.co.za Models of assembled Die Slide 12 © CSIR 2006 www.csir.co.za 3. Die manufacture, assembly and data capturing 21.521.521.525.5total 4electrode 3Fitting3Fitting3Fitting3Fitting 2Polish2Polish2Polish2Polish 7SER 3F grind3F grind...3F grind4F grind Heat trHeat trHeat tr1Heat tr Jig boreJig boreJig boreJig bore GrindingGrindingGrinding2Grinding 13.5DMLS13.5DMLS13.5DMLS2.5Milling HrsCostProcessHrsCostProcessHrsCostProcessHrsCostProcess Core 4Core 3Core 2Core 1 NB. Times...

  19. Self propagating high temperature synthesis of mixed carbide and boride powder systems for cutting tools manufacturing

    International Nuclear Information System (INIS)

    Vallauri, D.; Cola, P.L. de; Piscone, F.; Amato, I.

    2001-01-01

    TiC-TiB 2 composites have been produced via SHS technique starting from low cost raw materials like TiO 2 , B 4 C, Mg. The influence of the diluent phase (Mg, TiC) content on combustion temperature has been investigated. The use of magnesium as the reductant phase allowed acid leaching of the undesired oxide product (MgO), leaving pure hard materials with fine particle size suitable to be employed in cutting tools manufacturing through cold pressing and sintering route. The densification has shown to be strongly dependent on the wetting additions. The influence of the metal binder and wetting additions on the sintering process has been investigated. A characterization of the obtained materials was performed by the point of view of cutting tools life (hardness, toughness, strength). (author)

  20. Manufacturing of a high precision coil system for the Spanish Stellarator TJ-II

    International Nuclear Information System (INIS)

    Alonso, J.; Blaumoser, M.; Bieder, H.E.; Theisen, E.; Jeckle, A.; Brandl, M.; Mione, M.

    1995-01-01

    The flexible Heliac TJ-II is under construction at Ciemat in Madrid, Spain. This experimental device allows the investigation of plasmas in a wide range of magnetic field configurations. The rotational transform can be varied between 0.9 and 2.5. Shear variation is possible from -1% to 10%. The magnetic well ranges from 0 to 6%. The average major plasma radius is 1.5 m and the minor plasma dimensions are 0.4 m by 0.2 m. The average toroidal magnetic field is 1 T. The central part of TJ-II is a coil system called Hard Core. The manufacturing aspects of this component are described hereafter. The narrow range of tolerances of the different elements is consequence of the necessary precision of the coils that are located very close to the plasma. (orig.)

  1. Micro injection moulding process validation for high precision manufacture of thermoplastic elastomer micro suspension rings

    DEFF Research Database (Denmark)

    Calaon, M.; Tosello, G.; Elsborg Hansen, R.

    Micro injection moulding (μIM) is one of the most suitable micro manufacturing processes for flexible mass-production of multi-material functional micro components. The technology was employed in this research used to produce thermoplastic elastomer (TPE) micro suspension rings identified...... main μIM process parameters (melt temperature, injection speed, packing pressure) using the Design of Experiment statistical technique. Measurements results demonstrated the importance of calibrating mould´s master geometries to ensure correct part production and effective quality conformance...... on the frequency in order to improve the signal quality and assure acoustic reproduction fidelity. Production quality of the TPE rings drastically influence the product functionality. In the present study, a procedure for μIM TPE micro rings production optimization has been established. The procedure entail using...

  2. Continuous and pulsed laser high power beam combiner for additive manufacturing applications

    Science.gov (United States)

    Bassignana, Marta; Califano, Alessio; Pescarmona, Francesco; Braglia, Andrea; Perrone, Guido

    2018-02-01

    Laser-based additive manufacturing (AM) from metal powders is emerging as the new industrial revolution, although current fabrication approaches still require long mechanical post-processing to improve the final surface quality and meet the design tolerances. To overcome this limitation, the next generation machines are expected to complement laser AM with laser ablation (LA) to implement surface finishing and micro texturing already during the device growth process. With this aim, a new beam combiner to allow the real-time interchange of additive and subtractive processes using the same scanner head has been designed. Extensive tests have been carried out using a 6 kW continuous-wave laser similar to that used for the metal powder fusion and a nanosecond 100W pulsed source similar to that used for laser ablation.

  3. High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise.

    Science.gov (United States)

    Macgregor, Lewis J; Hunter, Angus M

    2018-01-01

    Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p exercise. Mean motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; pexercise. The firing rate of high-threshold motor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures.

  4. Development of Manufacturing Method of Highly Functional Material Gallic acid-CLA Ester Using Irradiation

    International Nuclear Information System (INIS)

    Cho, C. H.; Byun, M. W.; Jeong, I. Y.; Kim, D. H.

    2006-01-01

    Increasing interest and current trends for natural materials with various health beneficial functions by radiation (RT)-biotechnology (BT) fusion by developed countries. However, the information and development of new functional materials using the RT-BT fusion technology is still limited. The target material developed and manufactured by RT-BT fusion technology may have a multi-functional effect on human health and it can be applied for pharmaceutical materials as well as functional food ingredient. The market of functional new materials has been grown dramatically and a multi-functional material manufactured by RT-BT fusion technology may have a great economic impact for both the domestic and overseas market. Development of GA-CLA ester by chemical synthetic method. Transformation of linoleic acid to conjugated linoleic acid by irradiation. Identification and confirmation of the biological functions including antioxidative, cancer cell proliferation inhibition, anti-microbial, enhancement of immune response and lipid metabolism of GA-CLA ester. Increase industrial applicability of the new materials. Development of GA-CLA ester by chemical synthetic method(2 patents submitted). Development of the optimum methodology of GA-CLA and its derivative, octadeca-9,12-dienyl-3,4,5-trihydroxy benzoate). Identification and confirmation of biological activities of GA-CLA. Extramural funding from the Ministry of Commerce, Industry, and Energy subjected by gallic acid-fatty acid derivatives (205,000,000 Won). Provides the basic data for successful project 'Development of cosmeceutical and cosmetics using gallic acid fatty acid derivatives' funded by Ministry of Commerce, Industry, and Energy and collaboration with the Technology-invested venture company, SunBiotech, Co. and problem-solving for industrial application. Complete the patent procedure and publish the results to international or domestic peer-reviewed journals

  5. Damage parameters for non-metals in a high energy neutron environment

    International Nuclear Information System (INIS)

    Dell, G.F.; Berry, H.C.; Lazareth, O.W.; Goland, A.N.

    1980-01-01

    Simulation of radiation damage induced in monatomic and binary non-metals by FMIT and fusion neutrons is described. Damage produced by elastic scattering of recoil atoms and by ionization-assisted processes has been evaluated using the damage program DON. Displacement damage from gamma rays has been evaluated by using the technique of Oen and Holmes. A comparison of damage for an anticipated FMIT radiation environment generated by a coupled n-γ transport calculations and a fusion spectrum is made. Gamma-induced displacement damage is sufficiently small that it is dominated by neutron-induced recoil processes. Ionization-assisted displacements may be important depending upon the ionization cross section of the particular non-metal under consideration

  6. Radiation damage study in montmorillonites. Application to the high-level nuclear waste disposal in France

    International Nuclear Information System (INIS)

    Sorieul, St.

    2003-11-01

    Smectite is a major component of bentonite, a material considered for engineered barriers in high level nuclear wastes repositories (HLNWR). In order to predict the long-term performance of the bentonite, various physical and chemical factors such as, e.g., thermal gradient, redox potential or mechanical stresses are currently considered. By contrast, little is known about radiation effects in smectite, although it might affect the properties of this mineral through cumulative radiation damages produced by ionizing radiations. The present study focuses on radiation damage in montmorillonite considered herein as a simplified model of bentonite. Two reference clays have been selected, one from Liaoning (China, CHI), containing native radiation-induced defects, and the other (called MX) separated from the MX80 reference bentonite (Wyoming, USA). They are distinguished by layer composition, particularly iron content (1 % and 4 % for CHI and MX, respectively). Radiation effects have been studied by combining X-ray diffraction, Fourier transform infrared spectroscopy, Electron Paramagnetic Resonance (EPR) and Moessbauer spectroscopies. Ionizing irradiation induces two main effects. First, several paramagnetic point defects are identified as trapped holes located on oxygen atoms of the smectite structure. These defects are characterized by different thermal stabilities, according to annealing experiments. Their creation is limited by saturation curve with maximum damage around 100 MGy. The response of the two montmorillonites is different in terms of nature and production of point defects, indicating a role of layer composition and structural precursors. Besides, EPR and Moessbauer results show substantial modifications of the oxidation state of structural iron, which are sample and dose-dependent. Irradiation induces reduction and oxidation of iron in CHI and MX samples, respectively. Moreover, physico-chemical treatments show that intensity of redox effects varies

  7. Manufacturing ontology through templates

    Directory of Open Access Journals (Sweden)

    Diciuc Vlad

    2017-01-01

    Full Text Available The manufacturing industry contains a high volume of knowhow and of high value, much of it being held by key persons in the company. The passing of this know-how is the basis of manufacturing ontology. Among other methods like advanced filtering and algorithm based decision making, one way of handling the manufacturing ontology is via templates. The current paper tackles this approach and highlights the advantages concluding with some recommendations.

  8. Adropin levels and target organ damage secondary to high blood pressure in the ED.

    Science.gov (United States)

    Gulen, Bedia; Eken, Cenker; Kucukdagli, Okkes Taha; Serinken, Mustafa; Kocyigit, Abdurrahim; Kılıc, Elif; Uyarel, Hüseyin

    2016-11-01

    High blood pressure is still a challenge for emergency physicians to discern the patients that require further analysis to establish the existence of acute hypertensive target organ damage (TOD). The present study aimed to reveal that adropin levels are useful for detecting TOD in patients presenting with high blood pressure. Patients presenting with a blood pressure of more than 180/110 mm Hg were enrolled into the study. After a resting period of 15 minutes, patients' blood pressures were measured thrice at 5-minute intervals while the patients were sitting on a chair, and the average of these measurements was accepted as the baseline value. Blood samples were obtained for either adropin levels or possible TOD during the emergency department admission. A total of 119 patients were included in the study. The mean systolic and diastolic blood pressures of study patients were 204.8±23.2 and 108.3 ± 10.3, respectively, and 42% (n = 50) of the patients had TOD. Although the adropin levels were similar between the patients with or without TOD (TOD group = 195 pg/mL, interquartile range [IQR]: 178-201; no-TOD group = 196 pg/mL, IQR: 176-204 [P = .982]), it is significantly higher in normotensive patients (normotensive group = 289 pg/mL, IQR: 193-403) compared with the hypertensive ones (P high blood pressure to the emergency department. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Low Damage, High Anisotropy Inductively Coupled Plasma for Gallium Nitride based Devices

    KAUST Repository

    Ibrahim, Youssef H.

    2013-05-27

    Group III-nitride semiconductors possess unique properties, which make them versatile materials for suiting many applications. Structuring vertical and exceptionally smooth GaN profiles is crucial for efficient optical device operation. The processing requirements for laser devices and ridge waveguides are stringent as compared to LEDs and other electronic devices. Due to the strong bonding and chemically inert nature of GaN, dry etching becomes a critical fabrication step. The surface morphology and facet etch angle are analyzed using SEM and AFM measurements. The influence of different mask materials is also studied including Ni as well as a SiO2 and resist bilayer. The high selectivity Ni Mask is found to produce high sidewall angles ~79°. Processing parameters are optimized for both the mask material and GaN in order to achieve a highly anisotropic, smooth profile, without resorting to additional surface treatment steps. An optimizing a SF6/O2 plasma etch process resulted in smooth SiO2 mask sidewalls. The etch rate and GaN surface roughness dependence on the RF power was also examined. Under a low 2mTorr pressure, the RF and ICP power were optimized to 150W and 300W respectively, such that a smooth GaN morphology and sidewalls was achieved with reduced ion damage. The The AFM measurements of the etched GaN surface indicate a low RMS roughness ranging from 4.75 nm to 7.66 nm.

  10. Characterisation of high-temperature damage mechanisms of oxide dispersion strengthened (ODS) ferritic steels

    International Nuclear Information System (INIS)

    Salmon-Legagneur, Hubert

    2017-01-01

    The development of the fourth generation of nuclear power plants relies on the improvement of cladding materials, in order to achieve resistance to high temperature, stress and irradiation dose levels. Strengthening of ferritic steels through nano-oxide dispersion allows obtaining good mechanical strength at high temperature and good resistance to irradiation induced swelling. Nonetheless, studies available from open literature evidenced an unusual creep behavior of these materials: high anisotropy in time to rupture and flow behavior, low ductility and quasi-inexistent tertiary creep stage. These phenomena, and their still unclear origin are addressed in this study. Three 14Cr ODS steels rods have been studied. Their mechanical behavior is similar to those of other ODS steels from open literature. During creep tests, the specimens fractured by through crack nucleation and propagation from the lateral surfaces, followed by ductile tearing once the critical stress intensity factor was reached at the crack tip. Tensile and creep properties did not depend on the chemical environment of specimens. Crack propagation tests performed at 650 C showed a low value of the stress intensity factor necessary to start crack propagation. The cracks followed an intergranular path through the smaller-grained regions, which partly explains the anisotropy of high temperature strength. Notched specimens have been used to study the impact of the main loading parameters (deformation rate, temperature, stress triaxiality) on macroscopic crack initiation and stable propagation, from the central part of the specimens. These tests allowed revealing cavities created during high temperature loading, but unexposed to the external environment. These cavities showed a high chemical reactivity of the free surfaces in this material. The performed tests also evidenced different types of grain boundaries, which presented different damage development behaviors, probably due to differences in local

  11. Manufacturing Growth with Social Deficits. Environmental and Labour Issues in the High Tech Industry of Penang, Malaysia

    DEFF Research Database (Denmark)

    Wangel, Arne

    2001-01-01

    The economic downturn in 1997 was less severe in Malaysia compared to other countries in the region. However, as the manufacturing sector, in particular the high tech industries, lacks a strong national technological base and depends on exports, structural problems remain. The first part of the p......The economic downturn in 1997 was less severe in Malaysia compared to other countries in the region. However, as the manufacturing sector, in particular the high tech industries, lacks a strong national technological base and depends on exports, structural problems remain. The first part...... of the paper briefly provides key indicators of the economic recession. The second part describes the origin and structure of the high tech sector in Malaysia. Impressive growth has been achieved only as accompanied by a deepening dependency on trends in the global computer industry. The absence of innovative...... capacity makes it difficult to escape production segments, in which labour cost remains a key parameter. Thus, the competitive position of Malaysia is unstable and may erode. In the third part, the pattern of interests of the major stakeholders: authorities, corporate managers, workers, trade unions...

  12. Microstructural Damage During High-Strain Torsion Experiments on Calcite-Anhydrite Aggregates

    Science.gov (United States)

    Cross, A. J.; Skemer, P. A.

    2016-12-01

    Ductile shear zones play a critical role in localising deformation in the Earth's crust and mantle. Severe grain size reduction - a ubiquitous feature of natural mylonites - is commonly thought to cause strain weakening via a transition to grain size sensitive deformation mechanisms. Although grain size reduction is modulated by grain growth in single-phase aggregates, grain boundary pinning in well-mixed poly-phase composites can inhibit grain growth, leading to microstructural `damage' which is likely a critical element of strain localization in the lithosphere. While dynamic recrystallization has been widely explored in rock mechanics and materials science, the mechanisms behind phase-mixing remain poorly understood. In this contribution we present results from high-strain, deformation experiments on calcite-anhydrite composites. Experiments were conducted in torsion at T = 500-700°C and P 1.5 GPa, using the new Large Volume Torsion (LVT) solid-medium apparatus, to shear strains of 0.5-30. As shear strain increases, progressive thinning and necking of initially large (≤ 1 mm) calcite domains is observed, resulting in an increase in the proportion of interphase boundaries. Grain-size is negatively correlated with the fraction of interphase boundaries, such that calcite grains in well-mixed regions are significantly smaller than those in single-phase domains. Crucially, progressive deformation leads to a reduction in grain-size beyond the lower limit established by the grain size piezometer for mono-phase calcite, implying microstructural damage. These data therefore demonstrate continued microstructural evolution in two-phase composites that is not possible in single-phase aggregates. These observations mark a new `geometric' mechanism for phase mixing, complementing previous models for phase mixing involving chemical reactions, material diffusion, and/or grain boundary sliding.

  13. IL-6, Antioxidant Capacity and Muscle Damage Markers Following High-Intensity Interval Training Protocols.

    Science.gov (United States)

    Cipryan, Lukas

    2017-02-01

    The aim of this study was to investigate changes of interleukin-6 (IL-6), total antioxidant capacity (TAC) and muscle damage markers (creatine kinase (CK), myoglobin and lactate dehydrogenase (LDH)) in response to three different high-intensity interval training (HIIT) protocols of identical external work. Twelve moderately-trained males participated in the three HIIT trials which consisted of a warm-up, followed by 12 min of 15 s, 30 s or 60 s HIIT sequences with the work/rest ratio 1. The biochemical markers of inflammation, oxidative stress and muscle damage were analysed POST, 3 h and 24 h after the exercise. All HIIT protocols caused an immediate increase in IL-6, TAC, CK, myoglobin and LDH. The most pronounced between-trials differences were found for the POST-exercise changes in IL-6 (Effect size ± 90% confidence interval: 1.51 ± 0.63, 0.84 ± 0.34 and 1.80 ± 0.60 for the 15s/15s, 30s/30s and 60s/60s protocol, respectively) and myoglobin (1.11 ± 0.29, 0.45 ± 0.48 and 1.09 ± 0.22 for the 15s/15s, 30s/30s and 60s/60s protocol, respectively). There were no substantial between-trial differences in other biochemical variables. In conclusion, the 15s/15s and 60s/60s protocols might be preferred to the 30s/30s protocols in order to maximize the training stimulus.

  14. Conceptual Process for the Manufacture of Low-Enriched Uranium/Molybdenum Fuel for the High Flux Isotope Reactor

    International Nuclear Information System (INIS)

    Sease, J.D.; Primm, R.T. III; Miller, J.H.

    2007-01-01

    The U.S. nonproliferation policy 'to minimize, and to the extent possible, eliminate the use of HEU in civil nuclear programs throughout the world' has resulted in the conversion (or scheduled conversion) of many of the U.S. research reactors from high-enriched uranium (HEU) to low-enriched uranium (LEU). A foil fuel appears to offer the best option for using a LEU fuel in the High Flux Isotope Reactor (HFIR) without degrading the performance of the reactor. The purpose of this document is to outline a proposed conceptual fabrication process flow sheet for a new, foil-type, 19.75%-enriched fuel for HFIR. The preparation of the flow sheet allows a better understanding of the costs of infrastructure modifications, operating costs, and implementation schedule issues associated with the fabrication of LEU fuel for HFIR. Preparation of a reference flow sheet is one of the first planning steps needed in the development of a new manufacturing capacity for low enriched fuels for U.S. research and test reactors. The flow sheet can be used to develop a work breakdown structure (WBS), a critical path schedule, and identify development needs. The reference flow sheet presented in this report is specifically for production of LEU foil fuel for the HFIR. The need for an overall reference flow sheet for production of fuel for all High Performance Research Reactors (HPRR) has been identified by the national program office. This report could provide a starting point for the development of such a reference flow sheet for a foil-based fuel for all HPRRs. The reference flow sheet presented is based on processes currently being developed by the national program for the LEU foil fuel when available, processes used historically in the manufacture of other nuclear fuels and materials, and processes used in other manufacturing industries producing a product configuration similar to the form required in manufacturing a foil fuel. The processes in the reference flow sheet are within the

  15. Conceptual Process for the Manufacture of Low-Enriched Uranium/Molybdenum Fuel for the High Flux Isotope Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sease, J.D.; Primm, R.T. III; Miller, J.H.

    2007-09-30

    The U.S. nonproliferation policy 'to minimize, and to the extent possible, eliminate the use of HEU in civil nuclear programs throughout the world' has resulted in the conversion (or scheduled conversion) of many of the U.S. research reactors from high-enriched uranium (HEU) to low-enriched uranium (LEU). A foil fuel appears to offer the best option for using a LEU fuel in the High Flux Isotope Reactor (HFIR) without degrading the performance of the reactor. The purpose of this document is to outline a proposed conceptual fabrication process flow sheet for a new, foil-type, 19.75%-enriched fuel for HFIR. The preparation of the flow sheet allows a better understanding of the costs of infrastructure modifications, operating costs, and implementation schedule issues associated with the fabrication of LEU fuel for HFIR. Preparation of a reference flow sheet is one of the first planning steps needed in the development of a new manufacturing capacity for low enriched fuels for U.S. research and test reactors. The flow sheet can be used to develop a work breakdown structure (WBS), a critical path schedule, and identify development needs. The reference flow sheet presented in this report is specifically for production of LEU foil fuel for the HFIR. The need for an overall reference flow sheet for production of fuel for all High Performance Research Reactors (HPRR) has been identified by the national program office. This report could provide a starting point for the development of such a reference flow sheet for a foil-based fuel for all HPRRs. The reference flow sheet presented is based on processes currently being developed by the national program for the LEU foil fuel when available, processes used historically in the manufacture of other nuclear fuels and materials, and processes used in other manufacturing industries producing a product configuration similar to the form required in manufacturing a foil fuel. The processes in the reference flow sheet are

  16. The organ specificity in pathological damage of chronic intermittent hypoxia: an experimental study on rat with high-fat diet.

    Science.gov (United States)

    Wang, Hui; Tian, Jian-li; Feng, Shu-zhi; Sun, Ning; Chen, Bao-yuan; Zhang, Yun

    2013-09-01

    It is known today that sleep apnea hypopnea syndrome and its characteristic chronic intermittent hypoxia can cause damages to multiple organs, including the cardiovascular system, urinary system, and liver. It is still unclear, however, whether the damage caused by sleep apnea hypopnea syndrome and the severity of the damage are organ-specific. This research observed the pathological effects of chronic intermittent hypoxia on rat's thoracic aorta, myocardium, liver, and kidney, under the condition of lipid metabolism disturbance, through establishing the rat model of chronic intermittent hypoxia with high-fat diet by imitating the features of human sleep apnea hypopnea syndrome. In this model, 24 male Wistar rats were randomly divided into three groups: a control group fed by regular diet, a high-fat group fed by high-fat diet, and a high-fat plus intermittent hypoxia group fed by high-fat diet and treated with intermittent hypoxia 7 h a day. At the end of the ninth week, the pathological changes of rat's organs, including the thoracic aorta, myocardium, liver, and kidney are observed (under both optical microscopy and transmission electron microscopy). As the result of the experiment shows, while there was no abnormal effect observed on any organs of the control group, slight pathological changes were found in the organs of the high-fat group. For the high-fat plus intermittent hypoxia group, however, remarkably severer damages were found on all the organs. It also showed that the severity of the damage varies by organ in the high-fat plus intermittent hypoxia group, with the thoracic aorta being the worst, followed by the liver and myocardium, and the kidney being the slightest. Chronic intermittent hypoxia can lead to multiple-organ damage to rat with high-fat diet. Different organs appear to have different sensitivity to chronic intermittent hypoxia.

  17. The role of the substrate in the high energy boron implantation damage recovering

    International Nuclear Information System (INIS)

    Mica, I.; Di Piazza, L.; Laurin, L.; Mariani, M.; Mauri, A.G.; Polignano, M.L.; Ricci, E.; Sammiceli, F.; Spoldi, G.

    2009-01-01

    In this work the role of the Si substrate in the high energy boron implantation damage recovering is studied. The boron implants were carried out in Czochralski grown (1 0 0) polished Si substrates as well as in epitaxial Si layers grown on (1 0 0) Si by chemical vapor deposition. The boron implantation dose was 2 x 10 14 cm -2 and the implantation energy was 600 keV. The recovery annealing was a furnace annealing at 1000 deg. C for 40 min. The defects formed by high energy boron implantation have been observed with transmission electron microscopy (TEM). In order to increase the statistics some junctions were formed on the buried p-well and electrically characterized. For the epitaxial wafers it was found that the number and the size of the dislocations change according to the doping of the substrate. For the Czochralski wafers it was found that the morphology and the size of the dislocations change according to the presence of the wafer pre-annealing (whether conventional furnace annealing or Magic Denuded Zone process).

  18. High-Intensity Exercise Induced Oxidative Stress and Skeletal Muscle Damage in Postpubertal Boys and Girls: A Comparative Study.

    Science.gov (United States)

    Pal, Sangita; Chaki, Biswajit; Chattopadhyay, Sreya; Bandyopadhyay, Amit

    2018-04-01

    Pal, S, Chaki, B, Chattopadhyay, S, and Bandyopadhyay, A. High-intensity exercise induced oxidative stress and skeletal muscle damage in post-pubertal boys and girls: a comparative study. J Strength Cond Res 32(4): 1045-1052, 2018-The purpose of this study was to examine the sex variation in high-intensity exercise induced oxidative stress and muscle damage among 44 sedentary postpubertal boys and girls through estimation of postexercise release pattern of muscle damage markers like creatine kinase, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and oxidative stress markers like extent of lipid peroxidation (thiobarbituric acid-reactive substances) and catalase activity. Muscle damage markers like creatine kinase, LDH, ALT, and AST were measured before, immediately after, and 24 and 48 hours after high-intensity incremental treadmill running. Oxidative stress markers like thiobarbituric acid-reactive substances and catalase activity were estimated before and immediately after the exercise. Lipid peroxidation and serum catalase activity increased significantly in both groups after exercise (p exercise level at 24 and 48 hours after exercise in both the sexes, (p exercise, the pattern of postexercise release of these markers were found to be similar in both the groups. Accordingly, it has been concluded from the present investigation that high-intensity exercise induces significant oxidative stress and increases indices of skeletal muscle damage in both postpubertal girls and boys. However, postpubertal girls are relatively better protected from oxidative stress and muscle damage as compared to the boys of similar age and physical activity level. It is further evident that sex difference may not be apparent for all the biomarkers of muscle damage in this age group.

  19. Manufacturing And High Temperature Oxidation Properties Of Electro-Sprayed Fe-24.5% Cr-5%Al Powder Porous Metal

    Directory of Open Access Journals (Sweden)

    Lee Kee-Ahn

    2015-06-01

    Full Text Available Fe-Cr-Al based Powder porous metals were manufactured using a new electro-spray process, and the microstructures and high-temperature oxidation properties were examined. The porous materials were obtained at different sintering temperatures (1350°C, 1400°C, 1450°C, and 1500°C and with different pore sizes (500 μm, 450 μm, and 200 μm. High-temperature oxidation experiments (TGA, Thermal Gravimetry Analysis were conducted for 24 hours at 1000°C in a 79% N2+ 21% O2, 100 mL/min. atmosphere. The Fe-Cr-Al powder porous metals manufactured through the electro-spray process showed more-excellent oxidation resistance as sintering temperature and pore size increased. In addition, the fact that the densities and surface areas of the abovementioned powder porous metals had the largest effects on the metal’s oxidation properties could be identified.

  20. New generation of nuclear fuels: Stability of different stearates under high doses gamma irradiation in the manufacturing process

    Energy Technology Data Exchange (ETDEWEB)

    Lebeau, D.; Esnouf, S. [Den-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Gracia, J. [Den-Service d' Etudes des Combustibles et Matériaux à base d' Actinides (SECA), CEA, F-30207 Bagnols-sur-Cèze Cedex (France); Audubert, F. [Den-Service d' Analyse et de Caractérisation du Comportement des Combustibles (SA3C), CEA, F- 13115 Saint-Paul-lez-Durance (France); Ferry, M., E-mail: muriel.ferry@cea.fr [Den-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France)

    2017-07-15

    In the future reactors, the pellets radioactivity will increase due to the modification of the plutonium concentration. The stability of the organic additive used as lubricating/deagglomerating agent has thus to be evaluated. Up to now, zinc stearate is employed, but new additives are tested in this study and compared to zinc stearate. In a first part of this paper, the order of magnitude of the dose deposited in the stearates has been estimated. Afterward, three different stearates have been irradiated, using gamma-rays at doses as high as 2000 kGy. Two atmospheres of irradiation were tested, i.e. inert atmosphere and air. Samples were characterized using the following analytical tools: mass spectrometry, thermogravimetry and infrared spectroscopy. The objective is the evaluation of the ageing of these materials. In the nuclear fuel pellets manufacturing context, the candidate which could replace zinc stearate, if this one is too degraded to fulfill its role of lubricant in the pellets of the future manufacturing, has been determined. - Highlights: •Dose deposition estimation for different stearates. •Stearates radiolysis and radio-oxidization at high doses using gamma-rays. •H{sub 2} emission estimation as a function of atmosphere and dose. •Chemical modifications in stearates as a function of atmosphere and dose. •Comparison of three stearates.

  1. Nanoimprint wafer and mask tool progress and status for high volume semiconductor manufacturing

    Science.gov (United States)

    Matsuoka, Yoichi; Seki, Junichi; Nakayama, Takahiro; Nakagawa, Kazuki; Azuma, Hisanobu; Yamamoto, Kiyohito; Sato, Chiaki; Sakai, Fumio; Takabayashi, Yukio; Aghili, Ali; Mizuno, Makoto; Choi, Jin; Jones, Chris E.

    2016-10-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash* Imprint Lithography (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. There are many criteria that determine whether a particular technology is ready for wafer manufacturing. Defectivity and mask life play a significant role relative to meeting the cost of ownership (CoO) requirements in the production of semiconductor devices. Hard particles on a wafer or mask create the possibility of inducing a permanent defect on the mask that can impact device yield and mask life. By using material methods to reduce particle shedding and by introducing an air curtain system, the lifetime of both the master mask and the replica mask can be extended. In this work, we report results that demonstrate a path towards achieving mask lifetimes of better than 1000 wafers. On the mask side, a new replication tool, the FPA-1100 NR2 is introduced. Mask replication is required for nanoimprint lithography (NIL), and criteria that are crucial to the success of a replication platform include both particle control, resolution and image placement accuracy. In this paper we discuss the progress made in both feature resolution and in meeting the image placement specification for replica masks.

  2. High energy proton induced radiation damage of rare earth permanent magnet quadrupoles

    Science.gov (United States)

    Schanz, M.; Endres, M.; Löwe, K.; Lienig, T.; Deppert, O.; Lang, P. M.; Varentsov, D.; Hoffmann, D. H. H.; Gutfleisch, O.

    2017-12-01

    Permanent magnet quadrupoles (PMQs) are an alternative to common electromagnetic quadrupoles especially for fixed rigidity beam transport scenarios at particle accelerators. Using those magnets for experimental setups can result in certain scenarios, in which a PMQ itself may be exposed to a large amount of primary and secondary particles with a broad energy spectrum, interacting with the magnetic material and affecting its magnetic properties. One specific scenario is proton microscopy, where a proton beam traverses an object and a collimator in which a part of the beam is scattered and deflected into PMQs used as part of a diagnostic system. During the commissioning of the PRIOR (Proton Microscope for Facility for Antiproton and Ion Research) high energy proton microscope facility prototype at Gesellschaft für Schwerionenforschung in 2014, a significant reduction of the image quality was observed which was partially attributed to the demagnetization of the used PMQ lenses and the corresponding decrease of the field quality. In order to study this phenomenon, Monte Carlo simulations were carried out and spare units manufactured from the same magnetic material—single wedges and a fully assembled PMQ module—were deliberately irradiated by a 3.6 GeV intense proton beam. The performed investigations have shown that in proton radiography applications the above described scattering may result in a high irradiation dose in the PMQ magnets. This did not only decrease the overall magnetic strength of the PMQs but also caused a significant degradation of the field quality of an assembled PMQ module by increasing the parasitic multipole field harmonics which effectively makes PMQs impractical for proton radiography applications or similar scenarios.

  3. Lightweight Damage Tolerant, High-Temperature Radiators for Nuclear Power and Propulsion

    Science.gov (United States)

    Craven, Paul D.; SanSoucie, Michael P.

    2015-01-01

    is enabled. High thermal conductivity carbon fibers are lightweight, damage tolerant, and can be heated to high temperature. Areal densities in the NASA set target range of 2 to 4 kg/m2 (for enabling NEP) are achieved and with specific powers (kW/kg) a factor of about 7 greater than conventional metal fins and about 1.5 greater than carbon composite fins. Figure 2 shows one fin under test. All tests were done under vacuum conditions.

  4. High strength and high electrical conductivity Cu–Cr system alloys manufactured by hot rolling–quenching process and thermomechanical treatments

    International Nuclear Information System (INIS)

    Xia Chengdong; Zhang Wan; Kang Zhanyuan; Jia Yanlin; Wu Yifeng; Zhang Rui; Xu Genying; Wang Mingpu

    2012-01-01

    Highlights: ► HR–Q and thermomechanical treatments are successfully developed to manufacture Cu–Cr system alloys. ► Ordered fcc structure Cr precipitates are considered to be precursors of equilibrium bcc Cr precipitates. ► The Cr precipitates are responsible for the improvement of properties. ► Additions of Zr, Mg and Si bring about significant improvement in properties of Cu–Cr alloy. ► Good properties are ascribed to grain boundary strengthening, strain hardening and precipitation hardening. - Abstract: Cu–Cr system alloy strips were manufactured by an online hot rolling–quenching (HR–Q) process and subsequent thermomechanical treatments. The microstructure and properties of the alloys were investigated by observations of optical microscopy and transmission electron microscopy, and measurements of microhardness and electrical conductivity. The results show that the HR–Q process and thermomechanical treatments are successfully developed to manufacture Cu–Cr system alloy strips with good combinations of strength, conductivity and softening resistance. Ordered fcc structure Cr precipitates, which are decomposed from the thermomechanical treated alloys, are considered to be precursors to the formation of equilibrium bcc Cr precipitates and responsible for the improvement of properties during near peak aging. Small additions of Zr, Mg and Si effectively improve the hardness and softening resistance of Cu–Cr alloy, and slightly reduce the electrical conductivity. The achievement of high strength and high electrical conductivity in the alloys is ascribed to the interactions of grain boundary strengthening, strain hardening and precipitation hardening.

  5. Nickel alloys and high-alloyed special stainless steels. Properties, manufacturing, applications. 4. compl. rev. ed.

    International Nuclear Information System (INIS)

    Heubner, Ulrich; Kloewer, Jutta; Alves, Helena; Behrens, Rainer; Schindler, Claudius; Wahl, Volker; Wolf, Martin

    2012-01-01

    This book contains the following eight topics: 1. Nickel alloys and high-alloy special stainless steels - Material overview and metallurgical principles (U. Heubner); 2. Corrosion resistance of nickel alloys and high-alloy special stainless steels (U. Heubner); 3. Welding of nickel alloys and high-alloy special stainless steels (T. Hoffmann, M. Wolf); 4. High-temperature materials for industrial plant construction (J. Kloewer); 5. Nickel alloys and high-alloy special stainless steels as hot roll clad composites-a cost-effective alternative (C. Schindler); 6. Selected examples of the use of nickel alloys and high-alloy special stainless steels in chemical plants (H. Alves); 7. The use of nickel alloys and stainless steels in environmental engineering (V. Wahl); 8: Nickel alloys and high-alloy special stainless steels for the oil and gas industry (R. Behrens).

  6. Simulation and experimental study of high power microwave damage effect on AlGaAs/InGaAs pseudomorphic high electron mobility transistor

    International Nuclear Information System (INIS)

    Yu Xin-Hai; Chai Chang-Chun; Liu Yang; Yang Yin-Tang; Xi Xiao-Wen

    2015-01-01

    The high power microwave (HPM) damage effect on the AlGaAs/InGaAs pseudomorphic high electron mobility transistor (pHEMT) is studied by simulation and experiments. Simulated results suggest that the HPM damage to pHEMT is due to device burn-out caused by the emerging current path and strong electric field beneath the gate. Besides, the results demonstrate that the damage power threshold decreases but the energy threshold slightly increases with the increase of pulse-width, indicating that HPM with longer pulse-width requires lower power density but more energy to cause the damage to pHEMT. The empirical formulas are proposed to describe the pulse-width dependence. Then the experimental data validate the pulse-width dependence and verify that the proposed formula P = 55τ −0.06 is capable of quickly and accurately estimating the HPM damage susceptibility of pHEMT. Finally the interior observation of damaged samples by scanning electron microscopy (SEM) illustrates that the failure mechanism of the HPM damage to pHEMT is indeed device burn-out and the location beneath the gate near the source side is most susceptible to burn-out, which is in accordance with the simulated results. (paper)

  7. Nanocomposite Thermolectric Materials by High Pressure Powder Consolidation Manufacturing, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to NASA's need to develop advanced nanostructured thermolectric materials, UTRON is proposing an innovative high pressure powder consolidation...

  8. Nanocomposite Thermolectric Materials by High Pressure Powder Consolidation Manufacturing, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to NASA's need to develop advanced nanostructured thermolectric materials, UTRON is proposing an innovative high pressure powder consolidation...

  9. Spectroscopic study of subsurface damage in high purity silica glasses under UV irradiation

    International Nuclear Information System (INIS)

    Fournier, Jessica

    2011-01-01

    Defects present in subsurface damage, supposed to be possible damage precursors, have been studied by luminescence spectroscopy. Because of the difficulty to detect micro cracks, we have selected a model cracks based on indentations. Luminescence spectra performed under a 325 nm excitation wavelength (experimental condition close to that used on the LMJ) are be compared on indentation as well as laser damages. Luminescence experiments at low temperature and on etched samples are reported in order to complete data obtained for the different observed defects. (author) [fr

  10. Analysis techniques of charging damage studied on three different high-current ion implanters

    Science.gov (United States)

    Felch, S. B.; Larson, L. A.; Current, M. I.; Lindsey, D. W.

    1989-02-01

    One of the Greater Silicon Valley Implant Users' Group's recent activities has been to sponsor a round-robin on charging damage, where identical wafers were implanted on three different state-of-the-art, high-current ion implanters. The devices studied were thin-dielectric (250 Å SiO2), polysilicon-gate MOS capacitors isolated by thick field oxide. The three implanters involved were the Varian/Extrion 160XP, the Eaton/Nova 10-80, and the Applied Materials PI9000. Each implanter vendor was given 48 wafers to implant with 100 keV As+ ions at a dose of 1 × 1016 cm-2. Parameters that were varied include the beam current, electron flood gun current, and chamber pressure. The charge-to-breakdown, breakdown voltage, and leakage current of several devices before anneal have been measured. The results from these tests were inconclusive as to the physical mechanism of charging and as to the effectiveness of techniques to reduce its impact on devices. However, the methodology of this study is discussed in detail to aid in the planning of future experiments. Authors' industrial affiliations: S.B. Felch, Varian Research Center, 611 Hansen Way, Palo Alto, CA 94303, USA; L.A. Larson, National Semiconductor Corp., P.O. Box 58090, Santa Clara, CA 95052-8090, USA; M.I. Current, Applied Materials, 3050 Bowers Ave., Santa Clara, CA 95054, USA; D.W. Lindsey, Eaton/NOVA, 931 Benicia Ave, Sunnyvale, CA 94086, USA.

  11. Surface damage on 6H–SiC by highly-charged Xeq+ ions irradiation

    International Nuclear Information System (INIS)

    Zhang, L.Q.; Zhang, C.H.; Han, L.H.; Xu, C.L.; Li, J.J.; Yang, Y.T.; Song, Y.; Gou, J.; Li, J.Y.; Ma, Y.Z.

    2014-01-01

    Surface damage on 6H–SiC irradiated by highly-charged Xe q+ (q = 18, 26) ions to different fluences in two geometries was studied by means of AFM, Raman scattering spectroscopy and FTIR spectrometry. The FTIR spectra analysis shows that for Xe 26+ ions irradiation at normal incidence, a deep reflection dip appears at about 930 cm −1 . Moreover, the reflectance on top of reststrahlen band decreases as the ion fluence increases, and the reflectance at tilted incidence is larger than that at normal incidence. The Raman scattering spectra reveal that for Xe 26+ ions at normal incidence, surface reconstruction occurs and amorphous stoichiometric SiC and Si–Si and C–C bonds are generated and original Si–C vibrational mode disappears. And the intensity of scattering peaks decreases with increasing dose. The AFM measurement shows that the surface swells after irradiation. With increasing ion fluence, the step height between the irradiated and the unirradiated region increases for Xe 18+ ions irradiation; while for Xe 26+ ions irradiation, the step height first increases and then decreases with increasing ion fluence. Moreover, the step height at normal incidence is higher than that at tilted incidence by the irradiation with Xe 18+ to the same ion fluence. A good agreement between the results from the three methods is found

  12. Study on manufacturing technique of synthetic shock-absorbers for underground disposal of high-level radioactive wastes

    International Nuclear Information System (INIS)

    Iwasaki, Takashi; Onodera, Yoshio; Hayashi, Hiromichi; Ebina, Takeo; Nagase, Takako; Torii, Kazuo

    1997-01-01

    On the cse of underground disposal of high level radioactive wastes, natural bentonite is planned to be used for artificial barrier shock-absorber. This is due to expectation of sealing water or adsorbing nuclear materials using swelling and ion-exchanging capacities of smectite, which is a main component of bentonite. In this study, some swelling laminar compounds with various compositions and structures are synthesized to investigate their water sealing and nuclear adsorbing properties. And, according to their results, an optimum material is selected to develop its economic manufacturing method and investigate its alternative possibility for natural bentonite. From such reason, following two titled studies have been executed; 1) Synthesis of the swelling laminar compounds, and 2) Development of manufacturing technique of artificial shock-absorber. In 1995 FY, 1) Detail investigation on synthetic condition of double octahedral type smectite and 2) modeling of the smectite and stability of same type displacement for base of inducing the computer simulation for estimating creation process of optimum materials, were conducted. (G.K.)

  13. An Facile High-Density Polyethylene - Exfoliated Graphite - Aluminium Hydroxide Composite: Manufacture, Morphology, Structure, Antistatic and Fireproof Properties

    Directory of Open Access Journals (Sweden)

    Jihui LI

    2014-09-01

    Full Text Available Graphite intercalation compounds (GIC and exfoliated graphite (EG as raw materials were prepared with flake graphite, concentrated sulphuric acid (H2SO4, potassium bichromate (K2Cr2O7 and peracetic acid (CH3CO3H and characterized. Then, high-density polyethylene-exfoliated graphite (HDPE-EG composites were fabricated with HDPE and EG via in situ synthesis technique in the different mass ratio, and their resistivity values (ohms/sq were measured. Based on the resistivity values, it was discovered that HDPE-EG composite with the antistatic property could be fabricated while the mass ratio was 5.00 : 0.30. Last, HDPE-EG-aluminium hydroxide (HDPE-EG-Al(OH3 composites were manufactured with HDPE, GIC and Al(OH3 via the in situ synthesis-thermal expansion technique, and their resistivity values and limiting oxygen index (LOI values were measured. Based on the resistivity values and LOI values, it was discovered that HDPE-EG-Al(OH3 composite with the antistatic and fireproof property could be manufactured while HDPE, GICs and Al(OH3 of mass ratio was 5.00 : 0.30 : 1.00. Otherwise, the petal-like morphology and structure of HDPE-EG-Al(OH3 composite were characterized, which consisted of EG, HDPE and Al(OH3. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4275

  14. Celastrol ameliorates liver metabolic damage caused by a high-fat diet through Sirt1

    Directory of Open Access Journals (Sweden)

    Yinliang Zhang

    2017-01-01

    Full Text Available Objective: Celastrol was recently identified as a potential novel treatment for obesity. However, the effect of Celastrol on nonalcoholic fatty liver disease (NAFLD remains elusive. The aim of this study is to evaluate the role of Celastrol in NAFLD. Methods: Functional studies were performed using wild-type C57BL/6J (WT mice and liver specific Sirt1-deficient (LKO mice. The molecular mechanism was explored in primary mouse liver and primary hepatocytes. Results: When WT mice receiving a high-fat diet (HFD were treated with Celastrol, reductions in body weight, subcutaneous and visceral fat content, and liver lipid droplet formation were observed, along with reduced hepatic intracellular triglyceride and serum triglyceride, free fatty acid, and ALT concentrations. Furthermore, Celastrol decreased hepatic sterol regulatory element binding protein 1c (Srebp-1c expression, enhanced the phosphorylation of hepatic AMP-activated protein kinase α (AMPKα, and increased the expression of hepatic serine–threonine liver kinase B1 (LKB1. Additionally, Celastrol treatment improved glucose tolerance and insulin sensitivity in WT mice fed the HFD. Celastrol administration also improved the anti-inflammatory and anti-oxidative status by inhibiting nuclear factor kappa B (NFκB activity and the mRNA levels of proinflammatory cytokines and increasing mitochondrial DNA copy number and anti-oxidative stress genes expression in WT mice liver, in vivo and in vitro. Moreover, Celastrol induced hepatic Sirt1 expression in WT mice, in vivo and in vitro. These Celastrol-mediated protective effects in WT mice fed a HFD were abolished in LKO mice fed a HFD. It was more interesting that Celastrol aggravated HFD-induced liver damage in LKO mice fed a HFD by inhibiting the phosphorylation of AMPKα and boosting the translocation of NFκB into the nucleus, thereby resulting in the increase of Srebp-1c expression and the mRNA levels of liver proinflammatory cytokines

  15. Material Surface Damage under High Pulse Loads Typical for ELM Bursts and Disruptions in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Landman, I.S.; Pestchanyi, S.E.; Bazylev, B.N [Forschungszentrum Karlsruhe (Germany). Inst. for Pulsed Power and Microwave Technology; Safronov, V.M. [Troitsk Inst. for Innovation and Fusion Research (TRINITI) (Russian Federation); Garkusha, I.E. [Kharkov Inst. of Physics and Technology (KIPT) (Ukraine). Inst. of Plasma Physics

    2004-08-01

    The divertor armour material for the tokamak ITER will probably be carbon manufactured as fibre composites (CFC) and tungsten as either brush-like structures or thin plates. Disruptive pulse loads where the heat deposition Q may reach 10{sup 2} MJ/m{sup 2} on a time scale {tau} of 3 ms, or operation in the ELMy H-mode at repetitive loads with Q {approx} 3MJ/m{sup 2} and {tau}{approx}0.3 ms; deteriorate armour performance. This work surveys recent numerical and experimental investigations of erosion mechanisms at these off-normal regimes carried out at FZK, TRINITI, and IPP-Kharkov. The modelling uses the anisotropic thermomechanics code PEGASUS-3D for the simulation of CFC brittle destruction, the surface melt motion code MEMOS-1.5D for tungsten targets, and the radiation-magnetohydrodynamics code FOREV-2D for calculating the plasma impact and simulating the heat loads for the ITER regime. Experiments aimed at validating these codes are being carried out at the plasma gun facilities MK-200UG, QSPA-T, and QSPA-Kh50 which produce powerful streams of hydrogen plasma with Q=10-30MJ/m{sup 2} and {tau} = 0.03-0.5 ms. Essential results are, for CFC targets, the experiments at high heat loads and the development of a local overheating model incorporated in PEGASUS-3D, and for the tungsten targets the analysis of evaporation- and melt motion erosion on the base of MEMOS-1.5D calculations for repetitive ELMs.

  16. Material Surface Damage under High Pulse Loads Typical for ELM Bursts and Disruptions in ITER

    Science.gov (United States)

    Landman, I. S.; Pestchanyi, S. E.; Safronov, V. M.; Bazylev, B. N.; Garkusha, I. E.

    The divertor armour material for the tokamak ITER will probably be carbon manufactured as fibre composites (CFC) and tungsten as either brush-like structures or thin plates. Disruptive pulse loads where the heat deposition Q may reach 102 MJ/m 2 on a time scale Ïä of 3 ms, or operation in the ELMy H-mode at repetitive loads with Q âe 1/4 3 MJ/m2 and Ïä âe 1/4 0.3 ms, deteriorate armour performance. This work surveys recent numerical and experimental investigations of erosion mechanisms at these off-normal regimes carried out at FZK, TRINITI, and IPP-Kharkov. The modelling uses the anisotropic thermomechanics code PEGASUS-3D for the simulation of CFC brittle destruction, the surface melt motion code MEMOS-1.5D for tungsten targets, and the radiation-magnetohydrodynamics code FOREV-2D for calculating the plasma impact and simulating the heat loads for the ITER regime. Experiments aimed at validating these codes are being carried out at the plasma gun facilities MK-200UG, QSPA-T, and QSPA-Kh50 which produce powerful streams of hydrogen plasma with Q = 10–30 MJ/m2 and Ïä = 0.03–0.5 ms. Essential results are, for CFC targets, the experiments at high heat loads and the development of a local overheating model incorporated in PEGASUS-3D, and for the tungsten targets the analysis of evaporation- and melt motion erosion on the base of MEMOS-1.5D calculations for repetitive ELMs.

  17. Fatigue performance of laser additive manufactured Ti-6Al-4V in very high cycle fatigue (VHCF regime up to 109 cycles

    Directory of Open Access Journals (Sweden)

    Eric eWycisk

    2015-12-01

    Full Text Available Additive manufacturing technologies are in the process of establishing themselves as an alternative production technology to conventional manufacturing such as casting or milling. Especially laser additive manufacturing (LAM enables the production of metallic parts with mechanical properties comparable to conventionally manufactured components. Due to the high geometrical freedom in LAM the technology enables the production of ultra-light weight designs and therefore gains increasing importance in aircraft and space industry. The high quality standards of these industries demand predictability of material properties for static and dynamic load cases. However, fatigue properties especially in the very high cycle fatigue regime until 109 cycles have not been sufficiently determined yet. Therefore this paper presents an analysis of fatigue properties of laser additive manufactured Ti-6Al-4V under cyclic tension-tension until 107 cycles and tension-compression load until 109 cycles.For the analysis of laser additive manufactured titanium alloy Ti-6Al-4V Woehler fatigue tests under tension-tension and tension-compression were carried out in the high cycle and very high cycle fatigue regime. Specimens in stress-relieved as well as hot-isostatic-pressed conditions were analyzed regarding crack initiation site, mean stress sensitivity and overall fatigue performance. The determined fatigue properties show values in the range of conventionally manufactured Ti-6Al-4V with particularly good performance for hot-isostatic-pressed additive-manufactured material. For all conditions the results show no conventional fatigue limit but a constant increase in fatigue life with decreasing loads. No effects of test frequency on life span could be determined. However, independently of testing principle, a shift of crack initiation from surface to internal initiation could be observed with increasing cycles to failure.

  18. Assessment of DNA damage in car spray painters exposed to organic solvents by the high-throughput comet assay.

    Science.gov (United States)

    Londoño-Velasco, Elizabeth; Martínez-Perafán, Fabián; Carvajal-Varona, Silvio; García-Vallejo, Felipe; Hoyos-Giraldo, Luz Stella

    2016-05-01

    Occupational exposure as a painter is associated with DNA damage and development of cancer. Comet assay has been widely adopted as a sensitive and quantitative tool for DNA damage assessment at the individual cell level in populations exposed to genotoxics. The aim of this study was to assess the application of the high-throughput comet assay, to determine the DNA damage in car spray painters. The study population included 52 car spray painters and 52 unexposed subjects. A significant increase in the %TDNA median (p  0.05). The results showed an increase in DNA breaks in car spray painters exposed to organic solvents and paints; furthermore, they demonstrated the application of high-throughput comet assay in an occupational exposure study to genotoxic agents.

  19. Combined Bulk and Surface Radiation Damage Effects at Very High Fluences in Silicon Detectors: Measurements and TCAD Simulations

    CERN Document Server

    Moscatelli, F; Morozzi, A; Mendicino, R; Dalla Betta, G F; Bilei, G M

    2016-01-01

    In this work we propose a new combined TCAD radiation damage modelling scheme, featuring both bulk and surface radiation damage effects, for the analysis of silicon detectors aimed at the High Luminosity LHC. In particular, a surface damage model has been developed by introducing the relevant parameters (NOX, NIT) extracted from experimental measurements carried out on p-type substrate test structures after gamma irradiations at doses in the range 10-500 Mrad(Si). An extended bulk model, by considering impact ionization and deep-level cross-sections variation, was included as well. The model has been validated through the comparison of the simulation findings with experimental measurements carried out at very high fluences (2×1016 1 MeV equivalent n/cm2) thus fostering the application of this TCAD approach for the design and optimization of the new generation of silicon detectors to be used in future HEP experiments.

  20. Development of high damage threshold optics for petawatt-class short-pulse lasers

    International Nuclear Information System (INIS)

    Stuart, B.C.; Perry, M.D.; Boyd, R.D.

    1995-01-01

    The authors report laser-induced damage threshold measurements on pure and multilayer dielectrics and gold-coated optics at 1053 and 526 nm for pulse durations, τ, ranging from 140 fs to 1 ns. Damage thresholds of gold coatings are limited to 500 mJ/cm 2 in the subpicosecond range for 1053-nm pulses. In dielectrics, qualitative differences in the morphology of damage and a departure from the diffusion-dominated τ1/2 scaling indicate that damage results from plasma formation and ablation for τ≤10 ps and from conventional melting and boiling for τ>50 ps. A theoretical model based on electron production via multiphoton ionization, Joule heating, and collisional (avalanche) ionization is in quantitative agreement with both the pulsewidth and wavelength scaling of experimental results

  1. High throughput DNA damage quantification of human tissue with home-based collection device

    Energy Technology Data Exchange (ETDEWEB)

    Costes, Sylvain V.; Tang, Jonathan; Yannone, Steven M.

    2018-04-03

    Kits, methods and systems for providing a service to provide a subject with information regarding the state of a subject's DNA damage. Collection, processing and analysis of samples are also described.

  2. Damage invariant and high security acquisition of the internal fingerprint using optical coherence tomography

    CSIR Research Space (South Africa)

    Darlow, Luke N

    2016-11-01

    Full Text Available representation they offer. Using an emerging fingerprint acquisition technology – optical coherence tomography – to access an internal fingerprint under the skin surface, this paper serves to address two limitations of conventional scanners: fingertip skin damage...

  3. High throughput DNA damage quantification of human tissue with home-based collection device

    Science.gov (United States)

    Costes, Sylvain V.; Tang, Jonathan; Yannone, Steven M.

    2018-04-03

    Kits, methods and systems for providing a service to provide a subject with information regarding the state of a subject's DNA damage. Collection, processing and analysis of samples are also described.

  4. Manufacturing Technology for High Voltage Power Supplies (HVPS). Volume III - Procedural Details

    National Research Council Canada - National Science Library

    1996-01-01

    .... The thrust of this program was to improve the reliability of High Voltage Power Supplies (HVPS). This was accomplished conducting a comprehensive evaluation of the materials, components and processes used to produce HVPS...

  5. Damage observation in a high-manganese austenitic TWIP steel by synchrotron radiation computed tomography

    International Nuclear Information System (INIS)

    Lorthios, J.; Nguyen, F.; Gourgues, A.-F.; Morgeneyer, T.F.; Cugy, P.

    2010-01-01

    Internal damage below the fracture surface of a multiaxial specimen made of twinning-induced plasticity (TWIP) steel was observed by three-dimensional X-ray microtomography as very elongated 'primary' voids. Specific tools for the local damage analysis were developed. A gradient in void volume fraction was measured from the fracture surface down to the bulk of the scanned volume (from ∼0.06% to 90% in area fraction), indicating strongly localized final fracture.

  6. Challenges in high accuracy surface replication for micro optics and micro fluidics manufacture

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Calaon, Matteo

    2014-01-01

    Patterning the surface of polymer components with microstructured geometries is employed in optical and microfluidic applications. Mass fabrication of polymer micro structured products is enabled by replication technologies such as injection moulding. Micro structured tools are also produced...... by replication technologies such as nickel electroplating. All replication steps are enabled by a high precision master and high reproduction fidelity to ensure that the functionalities associated with the design are transferred to the final component. Engineered surface micro structures can be either...

  7. High Productivity DRIE solutions for 3D-SiP and MEMS Volume Manufacturing

    International Nuclear Information System (INIS)

    Puech, M; Thevenoud, J M; Launay, N; Arnal, N; Godinat, P; Andrieu, B; Gruffat, J M

    2006-01-01

    Emerging 3D-SiP technologies and high volume MEMS applications require high productivity mass production DRIE systems. The Alcatel DRIE product range has recently been optimised to reach the highest process and hardware production performances. A study based on sub-micron high aspect ratio structures encountered in the most stringent 3D-SiP has been carried out. The optimization of the Bosch process parameters has resulted in ultra high silicon etch rates, with unrivalled uniformity and repeatability leading to excellent process. In parallel, most recent hardware and proprietary design optimization including vacuum pumping lines, process chamber, wafer chucks, pressure control system, gas delivery are discussed. These improvements have been monitored in a mass production environment for a mobile phone application. Field data analysis shows a significant reduction of cost of ownership thanks to increased throughput and much lower running costs. These benefits are now available for all 3D-SiP and high volume MEMS applications. The typical etched patterns include tapered trenches for CMOS imagers, through silicon via holes for die stacking, well controlled profile angle for 3D high precision inertial sensors, and large exposed area features for inkjet printer heads and Silicon microphones

  8. Industrial based volume manufacturing of lightweight aluminium alloy panel components with high-strength and complex-shape for car body and chassis structures

    Science.gov (United States)

    Anyasodor, Gerald; Koroschetz, Christian

    2017-09-01

    To achieve the high volume manufacture of lightweight passenger cars at economic cost as required in the automotive industry, low density materials and new process route will be needed. While high strength aluminium alloy grades: AA7075 and AA6082 may provide the alternative material solution, hot stamping process used for high-strength and ultrahigh strength steels such as boron steel 22mnb5 can enable the volume manufacture of panel components with high-strength and complex-shape for car body and chassis structures. These aluminium alloy grades can be used to manufacture panel components with possible yield strengths ≥ 500 MPa. Due to the differences in material behaviors, hot stamping process of 22mnb5 cannot be directly applied to high strength aluminium alloy grades. Despite recorded successes in laboratories, researches and niche hot forming processes of high strength aluminium alloy grades, not much have been achieved for adequate and efficient volume manufacturing system applicable in the automotive industry. Due to lack of such system and based on expert knowledge in hot stamping production-line, AP&T presents in this paper a hot stamping processing route for high strength aluminium alloys been suitable for production-line development and volume manufacturing.

  9. Bulk damage and absorption in fused silica due to high-power laser applications

    Science.gov (United States)

    Nürnberg, F.; Kühn, B.; Langner, A.; Altwein, M.; Schötz, G.; Takke, R.; Thomas, S.; Vydra, J.

    2015-11-01

    Laser fusion projects are heading for IR optics with high broadband transmission, high shock and temperature resistance, long laser durability, and best purity. For this application, fused silica is an excellent choice. The energy density threshold on IR laser optics is mainly influenced by the purity and homogeneity of the fused silica. The absorption behavior regarding the hydroxyl content was studied for various synthetic fused silica grades. The main absorption influenced by OH vibrational excitation leads to different IR attenuations for OH-rich and low-OH fused silica. Industrial laser systems aim for the maximum energy extraction possible. Heraeus Quarzglas developed an Yb-doped fused silica fiber to support this growing market. But the performance of laser welding and cutting systems is fundamentally limited by beam quality and stability of focus. Since absorption in the optical components of optical systems has a detrimental effect on the laser focus shift, the beam energy loss and the resulting heating has to be minimized both in the bulk materials and at the coated surfaces. In collaboration with a laser research institute, an optical finisher and end users, photo thermal absorption measurements on coated samples of different fused silica grades were performed to investigate the influence of basic material properties on the absorption level. High purity, synthetic fused silica is as well the material of choice for optical components designed for DUV applications (wavelength range 160 nm - 260 nm). For higher light intensities, e.g. provided by Excimer lasers, UV photons may generate defect centers that effect the optical properties during usage, resulting in an aging of the optical components (UV radiation damage). Powerful Excimer lasers require optical materials that can withstand photon energy close to the band gap and the high intensity of the short pulse length. The UV transmission loss is restricted to the DUV wavelength range below 300 nm and

  10. The Swedish infant high-grade reflux trial: UTI and renal damage.

    Science.gov (United States)

    Nordenström, Josefin; Sjöström, Sofia; Sillén, Ulla; Sixt, Rune; Brandström, Per

    2017-04-01

    High-grade vesicoureteral reflux (VUR) in children is associated with recurrent urinary tract infection (UTI) and renal damage. Breakthrough UTI despite continuous antibiotic prophylaxis (CAP) during the first years of life is a matter of concern and evokes early intervention. We investigated whether early endoscopic treatment (ET) of VUR grade 4-5 can reduce the risk of UTI recurrence and renal scarring. This prospective, randomized, controlled, multicentre, 1-year follow-up trial comprised 77 infants, UTIs were reported. There were 27 recurrent febrile UTIs in 6 (16%) children in the ET group and in 10 (26%) in the CAP group (p = 0.43), in eight (36%) girls and eight (15%) boys (p = 0.039). Successful VUR outcome (VUR 0-2) was seen in 22 (59%) in the ET and eight (21%) in the CAP group (p = 0.0014). Multiple recurrences were only seen in patients with persistent dilating reflux at follow-up (p = 0.019). Deterioration on scintigraphy was seen in eight children (9 kidneys) with no difference between treatment groups (p = 0.48) or sex (p = 0.17). Renal deterioration was associated with high bladder capacity (BC) and large residual volume (PVR) at 1 year (p = 0.0092 and p = 0.041). Six of the eight children with renal deterioration had a recurrent UTI (p = 0.0032). Seven of nine renal units with deterioration were seen in children with persistent VUR 3-5 at follow-up. Univariable logistic regression identified female sex and high PVR as positive predictors for recurrent UTI (p = 0.039 and 0.034) and high PVR tended to predict renal deterioration (p = 0.053). No differences between the treatment groups regarding recurrent UTI and renal deterioration could be found. Increased PVR and female sex were positive predictors for UTI recurrences. VUR grade at follow-up was correlated to UTI recurrence and renal deterioration. This study did not show any difference between ET and CAP in reducing the risk of UTI recurrence or renal deterioration. The rate

  11. High fructose corn syrup use in beverages: Composition, manufacturing, properties, consumption, and health effects

    Science.gov (United States)

    High-fructose corn syrup (HFCS) has been used in beverages for more than 30 years. Technology to produce it was developed in the 1960s, it was introduced to the food and beverage industry as a liquid sweetener alternative to sucrose (sugar) in the 1970s, and it fully replaced sucrose in the USA in m...

  12. Metal additive manufacturing of a high-pressure micro-pump

    NARCIS (Netherlands)

    Wits, Wessel Willems; Weitkamp, Sander J.; van Es, J.; van Es, Johannes

    2013-01-01

    For the thermal control of future space applications pumped two-phase loops are an essential part to handle the increasing thermal power densities. This study investigates the design of a reliable, leak tight, low-weight and high-pressure micro-pump for small satellite applications. The developed

  13. Microstructural evolution in additive manufacturing with high power lasers : Deposition, characterization and performance

    NARCIS (Netherlands)

    Nenadl, Ondrej

    2017-01-01

    High power lasers provide time and cost effective method for metallic surface modification. In this work these modifications are explored as: 1) a simple melting and subsequent rapid solidification of a metallic surface – resulting in superior properties post-treatment; 2) deposition of an

  14. Influence of oxygen at high pressure on the induction of damage in barley seeds by gamma radiation

    International Nuclear Information System (INIS)

    Donaldson, E.; Nilan, R.A.; Konzak, C.F.

    1978-01-01

    The influence of oxygen pressure prior to, during, and after irradiation on the induction of radiation damage was investigated using Himalaya (C.I. 620) barley seeds. Seeds were adjusted to water contents of 2 to 14% and then irradiated with 60 Co gamma rays in vacuo or under various oxygen tensions. After irradiation, the seeds were rehydrated at approximately 0 0 C in water continuously bubbled with oxygen or nitrogen. Biological effects of the treatments were recorded as M 1 seedling injury. Seeds irradiated in oxygen pressure sustained two or three times more damage than those irradiated in vacuo followed by rehydrating in oxygenated water. Greater damage occurred when seeds were (a) exposed to oxygen pressure and the pressure released before irradiation, (b) irradiated under oxygen pressure, or (c) irradiated in vacuo and then exposed to oxygen pressure than when irradiated in vacuo and rehydrated in oxygenated water. These results suggest that seeds can be saturated with oxygen before irradiation and also that the radiation-induced sites (presumably free radicals) which react with the oxygen are somewhat stable in very dry seeds. That the reaction probably occurs before the seeds are rehydrated was demonstrated by the failure to remove the effect of oxygen pressure between high oxygen pressure treatment and irradiation. The results indicate that placing the seeds under oxygen pressure may increase the rate and extent of the reactions occurring during post-radiation storage of seeds in the presence of oxygen. The increase in damage associated with aerobic rehydration is partially lost during aerobic storage and is largely pre-empted when seeds are placed under oxygen pressure. The decrease in damage associated with aerobic rehydration is accompanied by an increase in damage occurring with anaerobic rehydration, suggesting that the reaction which leads to damage was initiated before rehydration and to the same oxygen sensitive sites

  15. High-energy electron irradiation of NdFeB permanent magnets: Dependence of radiation damage on the electron energy

    International Nuclear Information System (INIS)

    Bizen, Teruhiko; Asano, Yoshihiro; Marechal, Xavier-Marie; Seike, Takamitsu; Aoki, Tsuyoshi; Fukami, Kenji; Hosoda, Naoyasu; Yonehara, Hiroto; Takagi, Tetsuya; Hara, Toru; Tanaka, Takashi; Kitamura, Hideo

    2007-01-01

    High-energy electron-beam bombardment of Nd 2 Fe 14 B-type permanent magnets induces radiation damage characterized by a drop in the magnetic field. Experiments carried out at the SPring-8 booster synchrotron, with 4, 6, and 8 GeV electrons, show that the drop in magnetic field is energy dependent. Electromagnetic shower simulations suggest that most of the radiation damage happens in a small region around the irradiation axis, and that the contribution of neutrons with large scattering angles or with low energies to the magnetic field change is small

  16. High-energy electron irradiation of NdFeB permanent magnets: Dependence of radiation damage on the electron energy

    Energy Technology Data Exchange (ETDEWEB)

    Bizen, Teruhiko [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)]. E-mail: bizen@spring8.or.jp; Asano, Yoshihiro [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Marechal, Xavier-Marie [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Seike, Takamitsu [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Aoki, Tsuyoshi [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Fukami, Kenji [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hosoda, Naoyasu [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Yonehara, Hiroto [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Takagi, Tetsuya [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hara, Toru [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Tanaka, Takashi [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Kitamura, Hideo [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

    2007-05-11

    High-energy electron-beam bombardment of Nd{sub 2}Fe{sub 14}B-type permanent magnets induces radiation damage characterized by a drop in the magnetic field. Experiments carried out at the SPring-8 booster synchrotron, with 4, 6, and 8 GeV electrons, show that the drop in magnetic field is energy dependent. Electromagnetic shower simulations suggest that most of the radiation damage happens in a small region around the irradiation axis, and that the contribution of neutrons with large scattering angles or with low energies to the magnetic field change is small.

  17. Back-end interconnection. A generic concept for high volume manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Bosman, J.; Budel, T.; De Kok, C.J.G.M.

    2013-10-15

    The general method to realize series connection in thin film PV modules is monolithical interconnection through a sequence of laser scribes (P1, P2 and P3) and layer depositions. This method however implies that the deposition processes are interrupted several times, an undesirable situation in high volume processing. In order to eliminate this drawback we focus our developments on the so called 'back-end interconnection concept' in which series interconnection takes place AFTER the deposition of the functional layers of the thin film PV device. The process of making a back-end interconnection combines laser scribing, curing, sintering and inkjet processes. These different processes interacts with each other and are investigated in order to create processing strategies that are robust to ensure high volume production. The generic approach created a technology base that can be applied to any thin film PV technology.

  18. Manufacturing of High Quality Teachers for Chemistry Education at Higher Secondary Level in Current Era

    OpenAIRE

    R. Azmat

    2013-01-01

    Education is the most influential tool whose efficient use requires the power of determination, devoted work and sacrifice. As teachers are major handler of this tool therefore, they must possess qualities of high education and competency for deliver. Education extends attractive way of life, talent and manners which make an individual a fine civilian. Primary and secondary education is one of the foundation stone of development of children and country. It acts as a vital part in placing the ...

  19. On Limitations of the Ultrasonic Characterization of Pieces Manufactured with Highly Attenuating Materials

    Science.gov (United States)

    Ramos, A.; Moreno, E.; Rubio, B.; Calas, H.; Galarza, N.; Rubio, J.; Diez, L.; Castellanos, L.; Gómez, T.

    Some technical aspects of two Spanish cooperation projects, funded by DPI and Innpacto Programs of the R&D National Plan, are discussed. The objective is to analyze the common belief about than the ultrasonic testing in MHz range is not a tool utilizable to detect internal flaws in highly attenuating pieces made of coarse-grained steel. In fact high-strength steels, used in some safe industrial infrastructures of energy & transport sectors, are difficult to be inspected using the conventional "state of the art" in ultrasonic technology, due to their internal microstructures are very attenuating and coarse-grained. It is studied if this inspection difficulty could be overcome by finding intense interrogating pulses and advanced signal processing of the acquired echoes. A possible solution would depend on drastically improving signal-to-noise-ratios, by applying new advances on: ultrasonic transduction, HV electronics for intense pulsed driving of the testing probes, and an "ad-hoc" digital processing or focusing of the received noisy signals, in function of each material to be inspected. To attain this challenging aim on robust steel pieces would open the possibility of obtaining improvements in inspecting critical industrial components made of highly attenuating & dispersive materials, as new composites in aeronautic and motorway bridges, or new metallic alloys in nuclear area, where additional testing limitations often appear.

  20. Single-Crystal Tungsten Carbide in High-Temperature In-Situ Additive Manufacturing Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Kolopus, James A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Boatner, Lynn A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-05-18

    Nanoindenters are commonly used for measuring the mechanical properties of a wide variety of materials with both industrial and scientific applications. Typically, these instruments employ an indenter made of a material of suitable hardness bonded to an appropriate shaft or holder to create an indentation on the material being tested. While a variety of materials may be employed for the indenter, diamond and boron carbide are by far the most common materials used due to their hardness and other desirable properties. However, as the increasing complexity of new materials demands a broader range of testing capabilities, conventional indenter materials exhibit significant performance limitations. Among these are the inability of diamond indenters to perform in-situ measurements at temperatures above 600oC in air due to oxidation of the diamond material and subsequent degradation of the indenters mechanical properties. Similarly, boron carbide also fails at high temperature due to fracture. [1] Transition metal carbides possess a combination of hardness and mechanical properties at high temperatures that offer an attractive alternative to conventional indenter materials. Here we describe the technical aspects for the growth of single-crystal tungsten carbide (WC) for use as a high-temperature indenter material, and we examine a possible approach to brazing these crystals to a suitable mount for grinding and attachment to the indenter instrument. The use of a by-product of the recovery process is also suggested as possibly having commercial value.

  1. The Advanced High-Temperature Reactor (AHTR) for Producing Hydrogen to Manufacture Liquid Fuels

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Peterson, P.F.; Ott, L.

    2004-01-01

    Conventional world oil production is expected to peak within a decade. Shortfalls in production of liquid fuels (gasoline, diesel, and jet fuel) from conventional oil sources are expected to be offset by increased production of fuels from heavy oils and tar sands that are primarily located in the Western Hemisphere (Canada, Venezuela, the United States, and Mexico). Simultaneously, there is a renewed interest in liquid fuels from biomass, such as alcohol; but, biomass production requires fertilizer. Massive quantities of hydrogen (H2) are required (1) to convert heavy oils and tar sands to liquid fuels and (2) to produce fertilizer for production of biomass that can be converted to liquid fuels. If these liquid fuels are to be used while simultaneously minimizing greenhouse emissions, nonfossil methods for the production of H2 are required. Nuclear energy can be used to produce H2. The most efficient methods to produce H2 from nuclear energy involve thermochemical cycles in which high-temperature heat (700 to 850 C) and water are converted to H2 and oxygen. The peak nuclear reactor fuel and coolant temperatures must be significantly higher than the chemical process temperatures to transport heat from the reactor core to an intermediate heat transfer loop and from the intermediate heat transfer loop to the chemical plant. The reactor temperatures required for H2 production are at the limits of practical engineering materials. A new high-temperature reactor concept is being developed for H2 and electricity production: the Advanced High-Temperature Reactor (AHTR). The fuel is a graphite-matrix, coated-particle fuel, the same type that is used in modular high-temperature gas-cooled reactors (MHTGRs). The coolant is a clean molten fluoride salt with a boiling point near 1400 C. The use of a liquid coolant, rather than helium, reduces peak reactor fuel and coolant temperatures 100 to 200 C relative to those of a MHTGR. Liquids are better heat transfer fluids than gases

  2. NDE Evidence for the Damage Arrestment Performance of PRSEUS Composite Cube During High-Pressure Load Test

    Science.gov (United States)

    Johnston, Patrick H.; Parker, F. Raymond

    2013-01-01

    As an approach to light-weight, cost-effective and manufacturable structures required to enable the hybrid wing body aircraft, The Boeing Company, Inc. and NASA have developed the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept. A PRSEUS pressure cube was developed as a risk reduction test article to examine a new integral cap joint concept as part of a building block approach for technology development of the PRSEUS concept. The overall specimen strength exceeded the 18.4 psi load requirement as testing resulted in the cube reaching a final pressure load of around 48 psi prior to catastrophic failure. The cube pressure test verified that the joints and structure were capable of sustaining the required loads, and represented the first testing of joined PRSEUS structure. This paper will address the damage arrestment performance of the stitched PRSEUS structure. Following catastrophic failure of the cube, ultrasonic pulse-echo inspection found that the localized damage, surrounding a barely-visible impact damage site, did not change noticeably between just after impact and catastrophic failure of the cube, and did not play a role in the catastrophic failure event. Ultrasonic inspection of the remaining intact cube panels presented three basic types of indications: delaminations between laminae parallel to the face sheets, lying between face sheet and tear strap layers, or between tear strap and flange layers; delaminations above the noodles of stringers, frames or integral caps, lying within face sheet or tear strap layers; and delaminations between the laminae in the inner fillets of the integral caps, where pulloff stresses were expected to be highest. Delaminations of all three types were predominantly contained by the first row of stitches encountered. For the small fraction of delaminations extending beyond the first row of stitches, all were contained by the second stitch row.

  3. Design and high-volume manufacture of low-cost molded IR aspheres for personal thermal imaging devices

    Science.gov (United States)

    Zelazny, A. L.; Walsh, K. F.; Deegan, J. P.; Bundschuh, B.; Patton, E. K.

    2015-05-01

    The demand for infrared optical elements, particularly those made of chalcogenide materials, is rapidly increasing as thermal imaging becomes affordable to the consumer. The use of these materials in conjunction with established lens manufacturing techniques presents unique challenges relative to the cost sensitive nature of this new market. We explore the process from design to manufacture, and discuss the technical challenges involved. Additionally, facets of the development process including manufacturing logistics, packaging, supply chain management, and qualification are discussed.

  4. Characterisation of radiation damage in perovskite using high angular resolution electron channeling x-ray spectroscopy (HARECXS)

    International Nuclear Information System (INIS)

    Smith, K.L.; Zaluzec, N.J.

    2002-01-01

    Full text: Predicting and/or modelling the occurrence of radiation damage induced defects and their effects on physical properties (eg. amorphisation induced swelling, electrical conductivity., optical response etc.) in ceramic phases requires knowledge of the displacement energies, E d , of cations and anions in those phases. In this study, High Angular Resolution Electron Channelling X-ray Spectroscopy (HARECXS) spectra were collected from perovskite (CaTiO 3 ) samples that had been exposed to high-energy electrons or high-energy heavy ions. Calculations based on experimental data were then used to indicate the E d of the cations in perovskite. The HARECXS measurements were conducted on a Philips EM 420T AEM (LaB6 source, operated at 120 kV) fitted with an EDAX ultra thin window Si(Li) detector. The specimen was first manually oriented to an appropriate zone axis. Then control of the relative orientation of the incident probe was accomplished via direct computer control of the beam tilt coils, Typical acquisition times for a complete two-dimensional scan were 18-24 hours, while one dimensional scans ranged from 1-5 hours. Our experiments established that: a) HARECXS can detect radiation damage in perovskite caused by either high energy heavy ions or high energy electrons, b) the HARECXS signature of perovskite shows a systematic change with ion dose, c) HARECXS detects damage in perovskite that has been irradiated with 900kV electrons and does not detect damage in perovskite that has been irradiated with 620kV electrons, indicating the existance of an electron irradiation damage threshold. Calculations based on the latter results indicate that the displacement energy, E d of calcium and titanium in perovskite lie between 50 and 85eV. Copyright (2002) Australian Society for Electron Microscopy Inc

  5. Reconfigurable manufacturing system for agile mass customization manufacturing

    CSIR Research Space (South Africa)

    Xing, B

    2006-07-01

    Full Text Available Manufacturing companies are facing three challenges: low cost production of product, high quality standard and rapid responsiveness to customer requirements. These three goals are equally important for the manufacturing companies who want...

  6. Modular high power diode lasers with flexible 3D multiplexing arrangement optimized for automated manufacturing

    Science.gov (United States)

    Könning, Tobias; Bayer, Andreas; Plappert, Nora; Faßbender, Wilhelm; Dürsch, Sascha; Küster, Matthias; Hubrich, Ralf; Wolf, Paul; Köhler, Bernd; Biesenbach, Jens

    2018-02-01

    A novel 3-dimensional arrangement of mirrors is used to re-arrange beams from 1-D and 2-D high power diode laser arrays. The approach allows for a variety of stacking geometries, depending on individual requirements. While basic building blocks, including collimating optics, always remain the same, most adaptations can be realized by simple rearrangement of a few optical components. Due to fully automated alignment processes, the required changes can be realized in software by changing coordinates, rather than requiring customized mechanical components. This approach minimizes development costs due to its flexibility, while reducing overall product cost by using similar building blocks for a variety of products and utilizing a high grade of automation. The modules can be operated with industrial grade water, lowering overall system and maintenance cost. Stackable macro coolers are used as the smallest building block of the system. Each cooler can hold up to five diode laser bars. Micro optical components, collimating the beam, are mounted directly to the cooler. All optical assembly steps are fully automated. Initially, the beams from all laser bars propagate in the same direction. Key to the concept is an arrangement of deflectors, which re-arrange the beams into a 2-D array of the desired shape and high fill factor. Standard multiplexing techniques like polarization- or wavelengths-multiplexing have been implemented as well. A variety of fiber coupled modules ranging from a few hundred watts of optical output power to multiple kilowatts of power, as well as customized laser spot geometries like uniform line sources, have been realized.

  7. SBIR PHASE I FINAL REPORT: Adoption of High Performance Computational (HPC) Modeling Software for Widespread Use in the Manufacture of Welded Structures

    Energy Technology Data Exchange (ETDEWEB)

    Brust, Frederick W. [Engineering Mechanics Corporation of Columbus (Emc2), Columbus, OH (United States); Punch, Edward F. [Engineering Mechanics Corporation of Columbus (Emc2), Columbus, OH (United States); Kurth, Elizabeth A. [Engineering Mechanics Corporation of Columbus (Emc2), Columbus, OH (United States); Kennedy, James C. [Engineering Mechanics Corporation of Columbus (Emc2), Columbus, OH (United States)

    2013-12-02

    fabrication costs. VFT currently is tied to a commercial solver which makes it prohibitively expensive for use by SMEs, as there is a significant licensing cost for the solver - over and above for the relatively minimal cost for VFT. Emc2 developed this software code over a number of years in close cooperation with CAT (Peoria, IL), who currently uses this code exclusively for worldwide fabrication, product design and development activities. The use of VFT has allowed CAT to move directly from design to product fabrication and helped eliminate (to a large extent) new product prototyping and subsequent testing. Additionally, CAT has been able to eliminate/reduce costly one-of-a-kind appliances used to reduce distortion effects due to fabrication. In this context, SMEs can realize the same kind of improved product quality and reduced cost through adoption of the adapted version of VFT for design and subsequent manufacture of new products. Emc2's DOE SBIR Phase I effort successfully adapted VFT so that SMEs have access to this sophisticated and proven methodology that is quick, accurate and cost effective and available on-demand to address weld-simulation and fabrication problems prior to manufacture. The open source code, WARP3D, a high performance finite element code mainly used in fracture and damage assessment of structures, was modified so that computational weld problems can be solved efficiently on multiple processors and threads with VFT. The thermal solver for VFT, based on a series of closed form solution approximations, was enhanced for solution on multiple processors greatly increasing overall speed. In addition, the graphical user interface (GUI) has been tailored to integrate these solutions with WARP3D. The GUI is used to define all the weld pass descriptions, number of passes, material properties, consumable properties, weld speed, etc. for the structure to be modeled. The GUI was improved to make it user-friendly for engineers that are not experts in finite

  8. Sol-gel process for the manufacture of high power switches

    Science.gov (United States)

    Landingham, Richard L.; Satcher, Jr, Joe; Reibold, Robert

    2016-09-27

    According to one embodiment, a photoconductive semiconductor switch includes a structure of nanopowder of a high band gap material, where the nanopowder is optically transparent, and where the nanopowder has a physical characteristic of formation from a sol-gel process. According to another embodiment, a method includes mixing a sol-gel precursor compound, a hydroxy benzene and an aldehyde in a solvent thereby creating a mixture, causing the mixture to gel thereby forming a wet gel, drying the wet gel to form a nanopowder, and applying a thermal treatment to form a SiC nanopowder.

  9. Damage characterization of E-glass and C-glass fibre polymer composites after high velocity impact

    Science.gov (United States)

    Razali, N.; Sultan, M. T. H.; Cardona, F.; Jawaid, M.

    2017-12-01

    The purpose of this work is to identify impact damage on glass fibre reinforced polymer composite structures after high velocity impact. In this research, Type C-glass (600 g/m2) and Type E-glass (600 g/m2) were used to fabricate Glass Fibre-Reinforced Polymer composites (GFRP) plates. The panels were fabricated using a vacuum bagging and hot bounder method. Single stage gas gun (SSGG) was used to do the testing and data acquisition system was used to collect the damage data. Different types of bullets and different pressure levels were used for the experiment. The obtained results showed that the C-glass type of GFRP experienced more damage in comparison to E-glass type of materials based on the amount of energy absorbed on impact and the size of the damage area. All specimens underwent a partial fibre breakage but the laminates were not fully penetrated by the bullets. This indicated that both types of materials have high impact resistance even though the applied pressures of the gas gun were on the high range. We concluded that within the material specifications of the laminates including the type of glass fibre reinforcement and the thickness of the panels, those composite materials are safe to be applied in structural and body armour applications as an alternative to more expensive materials such as Kevlar and type S-glass fibre based panels.

  10. IFMIF High Flux Test Module-Recent progress in design and manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Leichtle, D. [Association FZK-EURATOM, Forschungszentrum Karlsruhe, Institut fuer Reaktorsicherheit, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)], E-mail: leichtle@irs.fzk.de; Arbeiter, F.; Dolensky, B.; Fischer, U.; Gordeev, S.; Heinzel, V.; Ihli, T.; Lang, K.-H. [Association FZK-EURATOM, Forschungszentrum Karlsruhe, Institut fuer Reaktorsicherheit, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Moeslang, A. [Association FZK-EURATOM, Forschungszentrum Karlsruhe, Institut fuer Materialforschung, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Simakov, S.P.; Slobodchuk, V.; Stratmanns, E. [Association FZK-EURATOM, Forschungszentrum Karlsruhe, Institut fuer Reaktorsicherheit, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)

    2008-12-15

    The International Fusion Material Irradiation Facility (IFMIF) is an accelerator driven neutron source for irradiation tests of candidate fusion reactor materials. Within the High Flux Test Module (HFTM) a testing volume of 0.5 l filled by qualified small scale specimens will be irradiated at displacement rates of 20-50 dpa/fpy in structural materials. The Forschungszentrum Karlsruhe (FZK) has developed a HFTM design which closely follows the design premise of maximising the space available for irradiation specimens in the IFMIF high flux zone and in addition allows keeping the temperature nearly constant in the rigs containing the specimen. Complementary analyses on nuclear, thermo-hydraulics and mechanical performance of the HFTM were performed to optimize the design. The present paper highlights the main design characteristics as well as recent progress achieved in this area. The contribution also includes (i) recommendations for the use of container, rig and capsule materials, and (ii) a description of the fabrication routes for the entire HFTM including brazing and filling procedures which are currently under development at the Forschungszentrum Karlsruhe.

  11. IFMIF High Flux Test Module-Recent progress in design and manufacturing

    International Nuclear Information System (INIS)

    Leichtle, D.; Arbeiter, F.; Dolensky, B.; Fischer, U.; Gordeev, S.; Heinzel, V.; Ihli, T.; Lang, K.-H.; Moeslang, A.; Simakov, S.P.; Slobodchuk, V.; Stratmanns, E.

    2008-01-01

    The International Fusion Material Irradiation Facility (IFMIF) is an accelerator driven neutron source for irradiation tests of candidate fusion reactor materials. Within the High Flux Test Module (HFTM) a testing volume of 0.5 l filled by qualified small scale specimens will be irradiated at displacement rates of 20-50 dpa/fpy in structural materials. The Forschungszentrum Karlsruhe (FZK) has developed a HFTM design which closely follows the design premise of maximising the space available for irradiation specimens in the IFMIF high flux zone and in addition allows keeping the temperature nearly constant in the rigs containing the specimen. Complementary analyses on nuclear, thermo-hydraulics and mechanical performance of the HFTM were performed to optimize the design. The present paper highlights the main design characteristics as well as recent progress achieved in this area. The contribution also includes (i) recommendations for the use of container, rig and capsule materials, and (ii) a description of the fabrication routes for the entire HFTM including brazing and filling procedures which are currently under development at the Forschungszentrum Karlsruhe

  12. Additive manufacturing.

    Science.gov (United States)

    Mumith, A; Thomas, M; Shah, Z; Coathup, M; Blunn, G

    2018-04-01

    Increasing innovation in rapid prototyping (RP) and additive manufacturing (AM), also known as 3D printing, is bringing about major changes in translational surgical research. This review describes the current position in the use of additive manufacturing in orthopaedic surgery. Cite this article: Bone Joint J 2018;100-B:455-60.

  13. Manufacturing technologies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Manufacturing Technologies Center is an integral part of Sandia National Laboratories, a multiprogram engineering and science laboratory, operated for the Department of Energy (DOE) with major facilities at Albuquerque, New Mexico, and Livermore, California. Our Center is at the core of Sandia`s Advanced Manufacturing effort which spans the entire product realization process.

  14. IFMIF high flux test module - recent progress in design and manufacturing

    International Nuclear Information System (INIS)

    Leichtle, D.; Arbeiter, F.; Dolensky, B.

    2007-01-01

    The International Fusion Material Irradiation Facility (IFMIF) is an accelerator driven neutron source for irradiation tests of candidate fusion reactor materials. Two 40 MeV deuterium beams with 125 mA each strike a liquid lithium jet target, producing a high intensity neutron flux up to 55 MeV, which penetrates the adjacent test modules. Within the High Flux Test Module (HFTM) a testing volume of 0.5 litres filled by qualified small scale specimens will be irradiated at displacement rates of 20-50 dpa/fpy in structural materials. The HFTM will also provide helium and hydrogen production to dpa ratios that reflect within the uncertainties the values expected in a DEMO fusion reactor The Forschungszentrum Karlsruhe (FZK) has developed a HFTM design which closely follows the design premise of maximising the space available for irradiation specimens in the IFMIF high flux zone and in addition allows keeping the temperature nearly constant in the rigs containing the specimen. Within the entire specimen stack the temperature deviation will be below about 15 K. The main design principles applied are (i) filling the gaps between the specimens with liquid metal, (ii) winding three separately controlled heater sections on the inner capsules and (iii) dividing the test rigs in a hot inner and a cold outer zone, which a separated by a gap filled with stagnant helium that serves as a thermal insulator. Channels between the outer covers (the cold parts) are cooled by helium gas at moderate pressure (3 bars at inlet) and temperature (50 C). 12 identical rigs holding the specimen capsules which are heated by segmented helically wound electrical heaters ensure a flexible loading scheme during IFMIF operation. Complementary analyses on nuclear, thermo-hydraulics and mechanical performance of the HFTM were performed to optimize the design. The present paper highlights the main design characteristics as well as recent progress achieved in this area. This includes the stiffening of

  15. Radiation damage by high-energy electrons in GaAs: DLTS investigation

    International Nuclear Information System (INIS)

    Lehmann, B.

    1991-10-01

    An isothermal variation of the DLTS technique is developed and applied to the study of displacement damage in GaAs, through the determination of threshold energies and displacement cross sections. Its results correspond to those of an LED based method. A pronounced anisotropy is found for the threshold energy. A linearly increasing displacement probability function is shown to properly model the displacement cross section in direction, as compared with the direction which requires only a single step function. Differences in the damage between these two directions are as large as a factor of two. (orig.) [de

  16. Jagiellonian University Radiation Damage in Silicon Particle Detectors in High Luminosity Experiments

    CERN Document Server

    Oblakowska-Mucha, A

    2017-01-01

    Radiation damage is nowadays the most serious problem in silicon particle detectors placed in the very harsh radiation environment. This problem will be even more pronounced after the LHC Upgrade because of extremely strong particle fluences never encountered before. In this review, a few aspects of radiation damage in silicon trackers are presented. Among them, the change in the silicon lattice and its influence on the detector performance are discussed. Currently applied solutions and the new ideas for future experiments will be also shown. Most of the results presented in this summary were obtained within the RD50 Collaboration

  17. Low-damage high-throughput grazing-angle sputter deposition on graphene

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.-T.; Gajek, M.; Raoux, S. [IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Casu, E. A. [IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Politecnico di Torino, Turin 10129 (Italy)

    2013-07-15

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

  18. Low-damage high-throughput grazing-angle sputter deposition on graphene

    International Nuclear Information System (INIS)

    Chen, C.-T.; Gajek, M.; Raoux, S.; Casu, E. A.

    2013-01-01

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications

  19. Low-damage high-throughput grazing-angle sputter deposition on graphene

    Science.gov (United States)

    Chen, C.-T.; Casu, E. A.; Gajek, M.; Raoux, S.

    2013-07-01

    Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

  20. Ultra-High-Performance Concrete And Advanced Manufacturing Methods For Modular Construction

    Energy Technology Data Exchange (ETDEWEB)

    Sawab, Jamshaid [Univ. of Houston, Houston, TX (United States); Lim, Ing [Univ. of Houston, Houston, TX (United States); Mo, Yi-Lung [Univ. of Houston, Houston, TX (United States); Li, Mo [Univ. of Houston, Houston, TX (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Guimaraes, Maria [Electric Power Research Inst. (EPRI), Knoxville, TN (United States)

    2016-04-13

    Small modular reactors (SMR) allow for less onsite construction, increase nuclear material security, and provide a flexible and cost-effective energy alternative. SMR can be factory-built as modular components, and shipped to desired locations for fast assembly. This project successfully developed a new class of ultra-high performance concrete (UHPC), which features a compressive strength greater than 22 ksi (150 MPa) without special treatment and self-consolidating characteristics desired for SMR modular construction. With an ultra-high strength and dense microstructure, it will facilitate rapid construction of steel plate-concrete (SC) beams and walls with thinner and lighter modules, and can withstand harsh environments and mechanical loads anticipated during the service life of nuclear power plants. In addition, the self-consolidating characteristics are crucial for the fast construction and assembly of SC modules with reduced labor costs and improved quality. Following the UHPC material development, the capacity of producing self-consolidating UHPC in mass quantities was investigated and compared to accepted self-consolidating concrete standards. With slightly adjusted mixing procedure using large-scale gravity-based mixers (compared with small-scale force-based mixer), the self-consolidating UHPC has been successfully processed at six cubic yards; the product met both minimum compressive strength requirements and self-consolidating concrete standards. Steel plate-UHPC beams (15 ft. long, 12 in. wide and 16 in. deep) and wall panels (40 in. X 40 in. X 3 in.) were then constructed using the self-consolidating UHPC without any external vibration. Quality control guidelines for producing UHPC in large scale were developed. When the concrete is replaced by UHPC in a steel plate concrete (SC) beam, it is critical to evaluate its structural behavior with both flexure and shear-governed failure modes. In recent years, SC has been widely used for buildings and nuclear

  1. Materials, manufacture and testing of pressurized components of high-power steam power plants

    International Nuclear Information System (INIS)

    Blind, D.; Foehl, J.; Issler, L.; Schellhammer, W.; Sturm, D.; Kussmaul, K.; Heinrich, D.; Meyer, H.J.; Prestel, W.

    1981-01-01

    This is the first German review of materials, production and testing of pressure components of high-capacity steam power plants. The authors have been working in this field for years; their special subject has been the availability and reliability of pressure vessels, in particular in nuclear engineering. Fundamentals are presented as well as the findings obtained at the state Materials Testing Institute in Stuttgart. The material is presented in a well-structured classification; the most recent international findings, especially of the USA, are presented. This is possible due to the close cooperation between the Stuttgart institute and a number of US research institutes. The new subject of fracture mechanics is treated in some detail; its fundamentals are discussed from the American point of view while German considerations - in particular of the Reactor Safety Commission - are taken into account in the field of applications. (orig.) [de

  2. High capacity electrode materials for batteries and process for their manufacture

    Science.gov (United States)

    Johnson, Christopher S.; Xiong, Hui; Rajh, Tijana; Shevchenko, Elena; Tepavcevic, Sanja

    2018-04-03

    The present invention provides a nanostructured metal oxide material for use as a component of an electrode in a lithium-ion or sodium-ion battery. The material comprises a nanostructured titanium oxide or vanadium oxide film on a metal foil substrate, produced by depositing or forming a nanostructured titanium dioxide or vanadium oxide material on the substrate, and then charging and discharging the material in an electrochemical cell from a high voltage in the range of about 2.8 to 3.8 V, to a low voltage in the range of about 0.8 to 1.4 V over a period of about 1/30 of an hour or less. Lithium-ion and sodium-ion electrochemical cells comprising electrodes formed from the nanostructured metal oxide materials, as well as batteries formed from the cells, also are provided.

  3. Design and Manufacturing of a High-Precision Sun Tracking System Based on Image Processing

    Directory of Open Access Journals (Sweden)

    Kianoosh Azizi

    2013-01-01

    Full Text Available Concentration solar arrays require greater solar tracking precision than conventional photovoltaic arrays. This paper presents a high precision low cost dual axis sun tracking system based on image processing for concentration photovoltaic applications. An imaging device is designed according to the principle of pinhole imaging, making sun rays to be received on a screen through pinhole and to be a sun spot. The location of the spot is used to adjust the orientation of the solar panel. A fuzzy logic controller is developed to achieve this goal. A prototype was built, and experimental results have proven the good performance of the proposed system and low error of tracking. The operation of this system is independent of geographical location, initial calibration, and periodical regulations.

  4. High Performance Transfer Press for Precision Manufacturing of Micro Metal Parts

    DEFF Research Database (Denmark)

    Mahshid, Rasoul

    for this technology and are available already in the market. Similar to conventional forming processes, the presence of a handling system can significantly improve the efficiency of the technology towards building a high performance transfer press for micro forming technology. To examine this possibility...... for actuation principle and mechanical grippers based on self-centering and friction principles. This study introduced a methodology for the analysis and characterization of this transfer system on component level and system level. Laser interferometry was used in combination with analytical models to predict...... the positioning ability of the actuator in a static as well as dynamic mode. In combination with an analysis of the grippers, a full description of the transfer precision inside the forming press was obtained. The current research involved integration of a handling system into an existing developed micro press...

  5. Simulation and Damage Analysis of an Accidental Jet Fire in a High-Pressure Compressed Pump Shelter

    OpenAIRE

    Jang, Chang Bong; Choi, Sang-Won

    2016-01-01

    Background: As one of the most frequently occurring accidents in a chemical plant, a fire accident may occur at any place where transfer or handling of combustible materials is routinely performed. Methods: In particular, a jet fire incident in a chemical plant operated under high pressure may bring severe damage. To review this event numerically, Computational Fluid Dynamics methodology was used to simulate a jet fire at a pipe of a compressor under high pressure. Results: For jet fire...

  6. Comparative study of AISI M3:2 high speed steel produced through different techniques of manufacturing

    International Nuclear Information System (INIS)

    Araujo Filho, Oscar Olimpio de

    2006-01-01

    In this work AISI M3:2 high speed steels obtained through different techniques of manufacturing, submitted to the same heat treatment procedure were evaluated by measuring their mechanical properties of transverse rupture strength and hardness. Sinter 23 obtained by hot isostatic pressing (HIP), VWM3C obtained by the conventional route and a M3:2 high speed steel obtained by cold compaction of water atomized powders and vacuum sintered with and without the addition of a small quantity of carbon were evaluated after the same heat treatment procedure. The vacuum sintered M3:2 high speed steel can be an alternative to the more expensive high speed steel produced by hot isostatic pressing and with similar properties presented by the conventional one. The characterization of the vacuum sintered M3:2 high speed steel was performed by measuring the densities of the green compacts and after the sintering cycle. The sintering produced an acceptable microstructure and densities near to the theoretical. The transverse rupture strength was evaluated by means of three point bending tests and the hardness by means of Rockwell C and Vickers tests. The technique of scanning electronic microscopy (SEM) was used to evaluate the microstructure and to establish a relation with the property of transverse rupture strength. The structure was determined by means of X-ray diffraction (XRD) patterns and the retained austenite was detected to all the conditions of heat treatment. The main contribution of this work is to establish a relation between the microstructure and the mechanical property of transverse rupture strength and to evaluate the AISI M3:2 vacuum sintered high speed steel as an alternative to the similar commercial high speed steels. (author)

  7. History of the development and manufacture of Czechoslovak high-frequency linear electron accelerators

    International Nuclear Information System (INIS)

    Cerny, R.

    2007-01-01

    The paper is structured as follows: History of linear accelerators worldwide (beginnings); Development of the Czechoslovak high-frequency linear electron accelerator (Layout and working principle; The first model of the accelerator and the Faculty of Technical and Nuclear Physics and cooperation with the Research Institute for Vacuum Electronics (VUVET); Continuing development of the accelerator at VUVET); Construction of linear accelerators at VUVET and their application (Construction of the accelerating unit; UR 4/1200 accelerator for radiation technology tests at VUVET; UR 4PR ('LUPUR') accelerator for the Nuclear Research Institute at Rez; UR 4/1200 technological accelerator for the Nuclear Research Institute at Rez; LPR4 accelerator for the Hungarian Academy of Sciences; L 4/1200 accelerators for the Research Institute of Cables and Insulators in Bratislava, CKD Semiconductors in Prague, Animal Feed Research Institute at Ivanka pri Dunaji, and Synthesia Semtin). Appendix contains paragraphs devoted to the Accelerator Dept. staff and equipment, key accelerator spare parts, and radiation safety at the accelerator department, (P.A.)

  8. High Volume Manufacturing of NanoEngineered High ZT Thermoelectrics for Multiple Energy Generation Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — SMI has teamed with a leading thermoelectric (TE) research group in order to optimize and convert high-performance TE materials developed in laboratory-scale into...

  9. High power Nd:YAG laser welding in manufacturing of vacuum vessel of fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, Tommi E-mail: tommi.jokinen@vtt.fi; Kujanpaeae, Veli E-mail: veli.kujanpaa@lut.fi

    2003-09-01

    Laser welding has shown many advantages over traditional welding methods in numerous applications. The advantages are mainly based on very precise and powerful heat source of laser light, which change the phenomena of welding process when compared with traditional welding methods. According to the phenomena of the laser welding, penetration is deeper and thus welding speed is higher. Because of the precise power source and high-welding speed, the heat input to the workpiece is small and distortions are reduced. Also, the shape of laser weld is less critical for distortions than traditional welds. For welding thick sections, the usability of lasers is not so practical than with thin sheets, because with power levels of present Nd:YAG lasers depth of penetration is limited up to about 10 mm by single-pass welding. One way to overcome this limitation is to use multi-pass laser welding, in which narrow gap and filler wire is applied. By this process, thick sections can be welded with smaller heat input and then smaller distortions and the process seems to be very effective comparing 'traditional' welding methods, not only according to the narrower gap. Another way to increase penetration and fill the groove is by using the so-called hybrid process, in which laser and GMAW (gas metal arc welding) are combined. In this paper, 20-mm thick austenitic stainless steel was welded using narrow gap configuration with a multi-pass technique. Two welding procedures were used: Nd:YAG laser welding with filler wire and with addition of GMAW, the hybrid process. In the welding experiments, it was noticed that both processes are feasible for welding thicker sections with good quality and with minimal distortions. Thus, these processes should be considered when the evaluation of the welding process is done for joining vacuum vessel sectors of ITER.

  10. Damage effect and mechanism of the GaAs pseudomorphic high electron mobility transistor induced by the electromagnetic pulse

    Science.gov (United States)

    Xiao-Wen, Xi; Chang-Chun, Chai; Gang, Zhao; Yin-Tang, Yang; Xin-Hai, Yu; Yang, Liu

    2016-04-01

    The damage effect and mechanism of the electromagnetic pulse (EMP) on the GaAs pseudomorphic high electron mobility transistor (PHEMT) are investigated in this paper. By using the device simulation software, the distributions and variations of the electric field, the current density and the temperature are analyzed. The simulation results show that there are three physical effects, i.e., the forward-biased effect of the gate Schottky junction, the avalanche breakdown, and the thermal breakdown of the barrier layer, which influence the device current in the damage process. It is found that the damage position of the device changes with the amplitude of the step voltage pulse. The damage appears under the gate near the drain when the amplitude of the pulse is low, and it also occurs under the gate near the source when the amplitude is sufficiently high, which is consistent with the experimental results. Project supported by the National Basic Research Program of China (Grant No. 2014CB339900), and the Open Fund of Key Laboratory of Complex Electromagnetic Environment Science and Technology, China Academy of Engineering Physics (CAEP) (Grant No. 2015-0214.XY.K).

  11. High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadis, H.

    2011-03-01

    Reported are the development and demonstration of a 17% efficient 25mm x 25mm crystalline Silicon solar cell and a 16% efficient 125mm x 125mm crystalline Silicon solar cell, both produced by Ink-jet printing Silicon Ink on a thin crystalline Silicon wafer. To achieve these objectives, processing approaches were developed to print the Silicon Ink in a predetermined pattern to form a high efficiency selective emitter, remove the solvents in the Silicon Ink and fuse the deposited particle Silicon films. Additionally, standard solar cell manufacturing equipment with slightly modified processes were used to complete the fabrication of the Silicon Ink high efficiency solar cells. Also reported are the development and demonstration of a 18.5% efficient 125mm x 125mm monocrystalline Silicon cell, and a 17% efficient 125mm x 125mm multicrystalline Silicon cell, by utilizing high throughput Ink-jet and screen printing technologies. To achieve these objectives, Innovalight developed new high throughput processing tools to print and fuse both p and n type particle Silicon Inks in a predetermined pat-tern applied either on the front or the back of the cell. Additionally, a customized Ink-jet and screen printing systems, coupled with customized substrate handling solution, customized printing algorithms, and a customized ink drying process, in combination with a purchased turn-key line, were used to complete the high efficiency solar cells. This development work delivered a process capable of high volume producing 18.5% efficient crystalline Silicon solar cells and enabled the Innovalight to commercialize its technology by the summer of 2010.

  12. Protecting Against Damage from Refraction of High Power Microwaves in the DIII-D Tokamak

    Directory of Open Access Journals (Sweden)

    Lohr John

    2017-01-01

    Full Text Available Several new protective systems are being installed on the DIII D tokamak to increase the safety margins for plasma operations with injected ECH power at densities approaching cutoff. Inadvertent overdense operation has previously resulted in reflection of an rf beam back into a launcher causing extensive arcing and melt damage on one waveguide line. Damage to microwave diagnostics, which are located on the same side of the tokamak as the ECH launchers, also has occurred. Developing a reliable microwave based interlock to protect the many vulnerable systems in DIII-D has proved to be difficult. Therefore, multiple protective steps have been taken to reduce the risk of damage in the future. Among these is a density interlock generated by the plasma control system, with setpoint determined by the ECH operators based on rf beam trajectories and plasma parameters. Also installed are enhanced video monitoring of the launchers, and an ambient light monitor on each of the waveguide systems, along with a Langmuir probe at the mouth of each launcher. Versatile rf monitors, measuring forward and reflected power in addition to the mode content of the rf beams, have been installed as the last miter bends in each waveguide line. As these systems are characterized, they are being incorporated in the interlock chains, which enable the ECH injection permits. The diagnostics most susceptible to damage from the ECH waves have also been fitted with a variety of protective devices including stripline filters, thin resonant notch filters tuned to the 110 GHz injected microwave frequency, blazed grating filters and shutters. Calculations of rf beam trajectories in the plasmas are performed using the TORAY ray tracing code with input from kinetic profile diagnostics. Using these calculations, strike points for refracted beams on the vacuum vessel are calculated, which allows evaluation of the risk of damage to sensitive diagnostics and hardware.

  13. Laser polishing of additive manufactured Ti alloys

    Science.gov (United States)

    Ma, C. P.; Guan, Y. C.; Zhou, W.

    2017-06-01

    Laser-based additive manufacturing has attracted much attention as a promising 3D printing method for metallic components in recent years. However, surface roughness of additive manufactured components has been considered as a challenge to achieve high performance. In this work, we demonstrate the capability of fiber laser in polishing rough surface of additive manufactured Ti-based alloys as Ti-6Al-4V and TC11. Both as-received surface and laser-polished surfaces as well as cross-section subsurfaces were analyzed carefully by White-Light Interference, Confocal Microscope, Focus Ion Beam, Scanning Electron Microscopy, Energy Dispersive Spectrometer, and X-ray Diffraction. Results revealed that as-received Ti-based alloys with surface roughness more than 5 μm could be reduce to less than 1 μm through laser polishing process. Moreover, microstructure, microhardness and wear resistance of laser-polished zone was investigated in order to examine the thermal effect of laser polishing processing on the substrate of additive manufactured Ti alloys. This proof-of-concept process has the potential to effectively improve the surface roughness of additive manufactured metallic alloy by local polishing method without damage to the substrate.

  14. Practical high temperature (80 °C) storage study of industrially manufactured Li-ion batteries with varying electrolytes

    Science.gov (United States)

    Genieser, R.; Loveridge, M.; Bhagat, R.

    2018-05-01

    A previous study is focused on high temperature cycling of industrially manufactured Li-ion pouch cells (NMC-111/Graphite) with different electrolytes at 80 °C [JPS 373 (2018) 172-183]. Within this article the same test set-up is used, with cells stored for 30 days at different open circuit potentials and various electrolytes instead of electrochemical cycling. The most pronounced cell degradation (capacity fade and resistance increase) happens at high potentials. However appropriate electrolyte formulations are able to suppress ageing conditions by forming passivating surface films on both electrodes. Compared with electrochemical cycling at 80 °C, cells with enhanced electrolytes only show a slight resistance increase during storage and the capacity fade is much lower. Additionally it is shown for the first time, that the resistance is decreasing and capacity is regained once these cells are cycled again at room temperature. This is not the case for electrolytes without additives or just vinylene carbonate (VC) as an additive. It is further shown that the resistance increase of cells with the other electrolytes is accompanied by a reduction of the cell volume during further cycling. This behaviour is likely related to the reduction of CO2 at the anode to form additional SEI layer components.

  15. Manufacturing parabolic mirrors

    CERN Multimedia

    CERN PhotoLab

    1975-01-01

    The photo shows the construction of a vertical centrifuge mounted on an air cushion, with a precision of 1/10000 during rotation, used for the manufacture of very high=precision parabolic mirrors. (See Annual Report 1974.)

  16. Quantification of damage in DNA recovered from highly degraded samples – a case study on DNA in faeces

    Directory of Open Access Journals (Sweden)

    Eveson J Paige

    2006-08-01

    Full Text Available Abstract Background Poorly preserved biological tissues have become an important source of DNA for a wide range of zoological studies. Measuring the quality of DNA obtained from these samples is often desired; however, there are no widely used techniques available for quantifying damage in highly degraded DNA samples. We present a general method that can be used to determine the frequency of polymerase blocking DNA damage in specific gene-regions in such samples. The approach uses quantitative PCR to measure the amount of DNA present at several fragment sizes within a sample. According to a model of random degradation the amount of available template will decline exponentially with increasing fragment size in damaged samples, and the frequency of DNA damage (λ can be estimated by determining the rate of decline. Results The method is illustrated through the analysis of DNA extracted from sea lion faecal samples. Faeces contain a complex mixture of DNA from several sources and different components are expected to be differentially degraded. We estimated the frequency of DNA damage in both predator and prey DNA within individual faecal samples. The distribution of fragment lengths for each target fit well with the assumption of a random degradation process and, in keeping with our expectations, the estimated frequency of damage was always less in predator DNA than in prey DNA within the same sample (mean λpredator = 0.0106 per nucleotide; mean λprey = 0.0176 per nucleotide. This study is the first to explicitly define the amount of template damage in any DNA extracted from faeces and the first to quantify the amount of predator and prey DNA present within individual faecal samples. Conclusion We present an approach for characterizing mixed, highly degraded PCR templates such as those often encountered in ecological studies using non-invasive samples as a source of DNA, wildlife forensics investigations and ancient DNA research. This method will

  17. Manufactured volvulus.

    Science.gov (United States)

    Zweifel, Noemi; Meuli, Martin; Subotic, Ulrike; Moehrlen, Ueli; Mazzone, Luca; Arlettaz, Romaine

    2013-06-01

    Malrotation with a common mesentery is the classical pathology allowing midgut volvulus to occur. There are only a few reports of small bowel volvulus without malrotation or other pathology triggering volvulation. We describe three cases of small bowel volvulus in very premature newborns with a perfectly normal intra-abdominal anatomy and focus on the question, what might have set off volvulation. In 2005 to 2008, three patients developed small bowel volvulus without any underlying pathology. Retrospective patient chart review was performed with special focus on clinical presentation, preoperative management, intraoperative findings, and potential causative explanations. Mean follow-up period was 46 months. All patients were born between 27 and 31 weeks (mean 28 weeks) with a birth weight between 800 and 1,000 g (mean 887 g). They presented with an almost identical pattern of symptoms including sudden abdominal distension, abdominal tenderness, erythema of the abdominal wall, high gastric residuals, and radiographic signs of ileus. All of them were treated with intensive abdominal massage or pelvic rotation to improve bowel movement before becoming symptomatic. Properistaltic maneuvers including abdominal massage and pelvic rotation may cause what we term a "manufactured" volvulus in very premature newborns. Thus, this practice was stopped. Georg Thieme Verlag KG Stuttgart · New York.

  18. Smart Manufacturing.

    Science.gov (United States)

    Davis, Jim; Edgar, Thomas; Graybill, Robert; Korambath, Prakashan; Schott, Brian; Swink, Denise; Wang, Jianwu; Wetzel, Jim

    2015-01-01

    Historic manufacturing enterprises based on vertically optimized companies, practices, market share, and competitiveness are giving way to enterprises that are responsive across an entire value chain to demand dynamic markets and customized product value adds; increased expectations for environmental sustainability, reduced energy usage, and zero incidents; and faster technology and product adoption. Agile innovation and manufacturing combined with radically increased productivity become engines for competitiveness and reinvestment, not simply for decreased cost. A focus on agility, productivity, energy, and environmental sustainability produces opportunities that are far beyond reducing market volatility. Agility directly impacts innovation, time-to-market, and faster, broader exploration of the trade space. These changes, the forces driving them, and new network-based information technologies offering unprecedented insights and analysis are motivating the advent of smart manufacturing and new information technology infrastructure for manufacturing.

  19. Radiation damage in He implanted silicon at high temperature using multi-energies

    CERN Document Server

    David, M L; Oliviero, E; Denanot, M F; Beaufort, M F; Declemy, A; Blanchard, C; Gerasimenko, N N; Barbot, J F

    2002-01-01

    He sup + ions were implanted at 800 deg. C into (1 0 0) silicon with multiple energies and selected fluences to get a number of displacement per atom constant in a large plateau. The ion-related defects have been mainly studied by transmission electron microscopy. Both the amount and the microstructure of defects have been found to be strongly dependent on the order of implants. Faceted cavities are only observed where damage overlapping occurs. The first implant provides thus nucleation sites for cavities. The generation of these sites is less efficient when using increasing energies because of damage recovery; fewer cavities are observed. Concurrently interstitial-type defects, left brace 1 1 3 right brace agglomerates, are formed. The observed state of growth of these left brace 1 1 3 right brace defects (rod-like and ribbon-like defects) is dependent on the implantation energy order but in any cases, no dislocation loops are observed even in the deepest damage region.

  20. The micro-mechanics of strength, durability and damage tolerance in composites: new insights from high resolution computed tomography

    Science.gov (United States)

    Spearing, S. Mark; Sinclair, Ian

    2016-07-01

    Recent work, led by the authors, on impact damage resistance, particle toughening and tensile fibre failure is reviewed in order to illustrate the use of high-resolution X-ray tomography to observe and quantify damage mechanisms in carbon fibre composite laminates. Using synchrotron and micro-focus X-ray sources resolutions of less than 1 μm have been routinely achieved. This enables individual broken fibres and the micromechanisms of particle toughening to be observed and quantified. The data for fibre failure, cluster formation and overall tensile strength are compared with model predictions. This allows strategies for future model development to be identified. The overall implications for using such high-resolution 3-D measurements to inform a “data-rich mechanics” approach to materials evaluation and modeling is discussed.

  1. Oxidation damage evaluation by non-destructive method for graphite components in high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Shibata, Taiju; Tada, Tatsuya; Sumita, Junya; Sawa, Kazuhiro

    2008-01-01

    To develop non-destructive evaluation methods for oxidation damage on graphite components in High Temperature Gas-cooled Reactors (HTGRs), the applicability of ultrasonic wave and micro-indentation methods were investigated. Candidate graphites, IG-110 and IG-430, for core components of Very High Temperature Reactor (VHTR) were used in this study. These graphites were oxidized uniformly by air at 500degC. The following results were obtained from this study. (1) Ultrasonic wave velocities with 1 MHz can be expressed empirically by exponential formulas to burn-off, oxidation weight loss. (2) The porous condition of the oxidized graphite could be evaluated with wave propagation analysis with a wave-pore interaction model. It is important to consider the non-uniformity of oxidized porous condition. (3) Micro-indentation method is expected to determine the local oxidation damage. It is necessary to assess the variation of the test data. (author)

  2. Highly corrosive and high strength Cr-Mn series austenite sintered steel, method of manufacturing the same and the usage

    International Nuclear Information System (INIS)

    Arai, Masahiko; Hirano, Tatsumi; Aono, Yasuhisa; Kato, Takahiko; Kondo, Yasuo; Inagaki, Masatoshi

    1998-01-01

    The steel of the present invention comprises a highly corrosive and high strength Cr-Mn series austenite sintered steel containing up to 0.1% of C, up to 1% of Si, up to 0.4% of N, from 9 to 25% of (Mn + Ni) within a range of more than 2% and up to 15% of Mn and from 14 to 20% of Cr, and it has an average crystal grain size of 1μm or less and comprises at least 90 vol% of an austenite phase. In addition, the alloy is incorporated with one or more elements of up to 3% of Mo, 1.0% of Ti, up to 2.0% of Zr and up to 1.0% of Nb in an amount of up to 2.0% in total of Ti, Zr and Nb. When these materials are used under the circumstance where materials are generally deteriorated in grain boundaries, since they are excellent in corrosion resistance and strength, remarkable effects can be attained in the improvement of the safety and the reliability of products. In addition, they are applied not only to a reactor core but also to a water-cooled circumstance and a circumstance where hydrogen exists, thereby capable of exhibiting remarkable effects. (T.M.)

  3. Biological Signatures of Brain Damage Associated with High Serum Ferritin Levels in Patients with Acute Ischemic Stroke and Thrombolytic Treatment

    Directory of Open Access Journals (Sweden)

    Mónica Millán

    2008-01-01

    Full Text Available Background and purpose: Increased body iron stores have been related to greater oxidative stress and brain injury in clinical and experimental cerebral ischemia and reperfusion. We aimed to investigate the biological signatures of excitotoxicity, inflammation and blood brain barrier disruption potentially associated with high serum ferritin levels-related damage in acute stroke patients treated with i.v. t-PA.

  4. Testing of bulk radiation damage of n-in-p silicon sensors for very high radiation environments

    Czech Academy of Sciences Publication Activity Database

    Hara, K.; Affolder, A.A.; Allport, P.P.; Bates, R.; Betancourt, C.; Böhm, Jan; Brown, H.; Buttar, C.; Carter, J. R.; Casse, G.; Mikeštíková, Marcela

    2011-01-01

    Roč. 636, č. 1 (2011), "S83"-"S89" ISSN 0168-9002 R&D Projects: GA MŠk LA08032 Institutional research plan: CEZ:AV0Z10100502 Keywords : p-bulk silicon * microstrip * charge collection * radiation damage Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.207, year: 2011 http://dx.doi.org/10.1016/j.nima.2010.04.090

  5. Efficient Phase Locking of Fiber Amplifiers Using a Low-Cost and High-Damage-Threshold Phase Control System

    International Nuclear Information System (INIS)

    Pu, Zhou; Yan-Xing, Ma; Xiao-Lin, Wang; Hao-Tong, Ma; Xiao-Jun, Xu; Ze-Jin, Liu

    2010-01-01

    We propose a low-cost and high-damage-threshold phase control system that employs a piezoelectric ceramic transducer modulator controlled by a stochastic parallel gradient descent algorithm. Efficient phase locking of two fiber amplifiers is demonstrated. Experimental results show that energy encircled in the target pinhole is increased by a factor of 1.76 and the visibility of the fringe pattern is as high as 90% when the system is in close-loop. The phase control system has potential in phase locking of large-number and high-power fiber laser endeavors. (fundamental areas of phenomenology (including applications))

  6. Microstructure-Based Counterfeit Detection in Metal Part Manufacturing

    Science.gov (United States)

    Dachowicz, Adam; Chaduvula, Siva Chaitanya; Atallah, Mikhail; Panchal, Jitesh H.

    2017-11-01

    Counterfeiting in metal part manufacturing has become a major global concern. Although significant effort has been made in detecting the implementation of such counterfeits, modern approaches suffer from high expense during production, invasiveness during manufacture, and unreliability in practice if parts are damaged during use. In this paper, a practical microstructure-based counterfeit detection methodology is proposed, which draws on inherent randomness present in the microstructure as a result of the manufacturing process. An optical Physically Unclonable Function (PUF) protocol is developed which takes a micrograph as input and outputs a compact, unique string representation of the micrograph. The uniqueness of the outputs and their robustness to moderate wear and tear is demonstrated by application of the methodology to brass samples. The protocol is shown to have good discriminatory power even between samples manufactured in the same batch, and runs on the order of several seconds per part on inexpensive machines.

  7. The numerical high cycle fatigue damage model of fillet weld joint under weld-induced residual stresses

    Science.gov (United States)

    Nguyen Van Do, Vuong

    2018-04-01

    In this study, a development of nonlinear continuum damage mechanics (CDM) model for multiaxial high cycle fatigue is proposed in which the cyclic plasticity constitutive model has been incorporated in the finite element (FE) framework. T-joint FE simulation of fillet welding is implemented to characterize sequentially coupled three-dimensional (3-D) of thermo-mechanical FE formulation and simulate the welding residual stresses. The high cycle fatigue damage model is then taken account into the fillet weld joints under the various cyclic fatigue load types to calculate the fatigue life considering the residual stresses. The fatigue crack initiation and the propagation in the present model estimated for the total fatigue is compared with the experimental results. The FE results illustrated that the proposed high cycle fatigue damage model in this study could become a powerful tool to effectively predict the fatigue life of the welds. Parametric studies in this work are also demonstrated that the welding residual stresses cannot be ignored in the computation of the fatigue life of welded structures.

  8. High-light damage in air-dry thalli of the old forest lichen Lobaria pulmonaria - interactions of irradiance, exposure duration and high temperature

    International Nuclear Information System (INIS)

    Gauslaa, Y.; Solhaug, K.A.

    1999-01-01

    High-light damage in air-dry thalli of Lobaria pulmonaria were measured in the laboratory as reductions in maximal PSII efficiency (FV/FM) after a 48 h recovery in a hydrated state at low light to account for permanent damage. Thalli treated with the lowest light dose (90 mol photons m −2 ) recovered normal FV/FM-values with increasing irradiances (400–700 nm) up to 1000 µmol photons m −2 s −1 . Doubling this dose lowered the threshold level for damage from 1000 to 320 µmol photons m −2 s −1 , and reduced FV/FM at 1000 µmol photons m −2 s −1 by more than 50%. A second doubling of the dose to 360 mol photons m −2 caused damage at 200 µmol photons m −2 s −1 , and a nearly complete cessation of PSII efficiency occurred at 1000 µmol photons m −2 s −1 . No reciprocity of irradiance and duration of illumination for PSII function was found. The measured time-dependent decrease in FV/FM was remarkably similar for the naturally coupled, but artificially separated, light and temperature factors. Therefore, the damage of high light on desiccated L. pulmonaria seemed to be an additive effect of high irradiance and high temperatures. Air-dry thalli were highly heat susceptible, being affected already at temperatures around 40 °C. Logging operations in forests are likely to raise the solar radiation at remaining lichen sites to destructive levels. (author)

  9. Effects of Nitrogen Content on the HAZ Softening of Ti-Containing High Strength Steels Manufactured by Accelerated Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Kook-soo; Jung, Ho-shin; Park, Chan [Pukyong National University, Busan (Korea, Republic of)

    2017-03-15

    The effects of nitrogen content on the HAZ softening of Ti-containing high strength steels manufactured by accelerating cooling were investigated and interpreted in terms of the microstructures in the softening zone. Regardless of their content, all of the steels investigated showed a softened zone 9-10 mm wide. The minimum hardness in the zone, however, was different, with lower hardness in the higher nitrogen content steel. Microstructural observations of the steel showed that the amount of soft ferrite was increased in the zone with an increase of nitrogen content of the steel, suggesting that microstructural evolution in the HAZ is influenced by the nitrogen content. Measurements of TiN particles showed that the degree of particles coarsening in the HAZ was lower in the higher nitrogen content steel. Therefore, it is believed that finer TiN particles in the HAZ inhibit austenite grain growth more effectively, and lead to an accelerated ferrite transformation in higher nitrogen content steel, resulting in a higher amount of soft ferrite microstructure in the softened zone.

  10. High Throughput Manufacturing of Thin-Film CdTe Photovoltaic Materials; Final Subcontract Report, 16 November 1993-31 December 1998

    International Nuclear Information System (INIS)

    Sandwisch, D.W.

    1999-01-01

    This report describes work performed by Solar Cells, Inc. (SCI), during this Photovoltaic Manufacturing Technology (PVMaT) subcontract. Cadmium telluride (CdTe) is recognized as one of the leading materials for low-cost photovoltaic modules. SCI has developed this technology and is preparing to scale its pilot production capabilities to a multi-megawatt level. This four-phase PVMaT subcontract supports these efforts. The work was related to product definition, process definition, equipment engineering, and support programs development. In the area of product definition and demonstration, two products were specified and demonstrated-a grid-connected, frameless, high-voltage product that incorporates a pigtail potting design and a remote low-voltage product that may be framed and may incorporate a junction box. SCI produced a 60.3-W thin-film CdTe module with total-area efficiency of 8.4%; SCI also improved module pass rate on the interim qualification test protocol from less than 20% to 100% as a result of work related to the subcontract. In the manufacturing process definition area, the multi-megawatt manufacturing process was defined, several of the key processes were demonstrated, and the process was refined and proven on a 100-kW pilot line that now operates as a 250-kW line. In the area of multi-megawatt manufacturing-line conceptual design review, SCI completed a conceptual layout of the multi-megawatt lines. The layout models the manufacturing line and predicts manufacturing costs. SCI projected an optimized capacity, two-shift/day operation of greater than 25 MW at a manufacturing cost of below$1.00/W

  11. High Throughput Manufacturing of Thin-Film CdTe Photovoltaic Materials; Final Subcontract Report, 16 November 1993-31 December 1998

    Energy Technology Data Exchange (ETDEWEB)

    Sandwisch, D. W. (Solar Cells, Inc.)

    1999-09-02

    This report describes work performed by Solar Cells, Inc. (SCI), during this Photovoltaic Manufacturing Technology (PVMaT) subcontract. Cadmium telluride (CdTe) is recognized as one of the leading materials for low-cost photovoltaic modules. SCI has developed this technology and is preparing to scale its pilot production capabilities to a multi-megawatt level. This four-phase PVMaT subcontract supports these efforts. The work was related to product definition, process definition, equipment engineering, and support programs development. In the area of product definition and demonstration, two products were specified and demonstrated-a grid-connected, frameless, high-voltage product that incorporates a pigtail potting design and a remote low-voltage product that may be framed and may incorporate a junction box. SCI produced a 60.3-W thin-film CdTe module with total-area efficiency of 8.4%; SCI also improved module pass rate on the interim qualification test protocol from less than 20% to 100% as a result of work related to the subcontract. In the manufacturing process definition area, the multi-megawatt manufacturing process was defined, several of the key processes were demonstrated, and the process was refined and proven on a 100-kW pilot line that now operates as a 250-kW line. In the area of multi-megawatt manufacturing-line conceptual design review, SCI completed a conceptual layout of the multi-megawatt lines. The layout models the manufacturing line and predicts manufacturing costs. SCI projected an optimized capacity, two-shift/day operation of greater than 25 MW at a manufacturing cost of below $1.00/W.

  12. Manufacturing and High Heat Flux Testing of Brazed Flat-Type W/CuCrZr Plasma Facing Components

    Science.gov (United States)

    Lian, Youyun; Liu, Xiang; Feng, Fan; Chen, Lei; Cheng, Zhengkui; Wang, Jin; Chen, Jiming

    2016-02-01

    Water-cooled flat-type W/CuCrZr plasma facing components with an interlayer of oxygen-free copper (OFC) have been developed by using vacuum brazing route. The OFC layer for the accommodation of thermal stresses was cast onto the surface of W at a temperature range of 1150 °C-1200 °C in a vacuum furnace. The W/OFC cast tiles were vacuum brazed to a CuCrZr heat sink at 940 °C using the silver-free filler material CuMnSiCr. The microstructure, bonding strength, and high heat flux properties of the brazed W/CuCrZr joint samples were investigated. The W/Cu joint exhibits an average tensile strength of 134 MPa, which is about the same strength as pure annealed copper. High heat flux tests were performed in the electron beam facility EMS-60. Experimental results indicated that the brazed W/CuCrZr mock-up experienced screening tests of up to 15 MW/m2 and cyclic tests of 9 MW/m2 for 1000 cycles without visible damage. supported by National Natural Science Foundation of China (No. 11205049) and the National Magnetic Confinement Fusion Science Program of China (No. 2011GB110004)

  13. Acute Oxidative Effect and Muscle Damage after a Maximum 4 Min Test in High Performance Athletes.

    Directory of Open Access Journals (Sweden)

    Heros Ribeiro Ferreira

    Full Text Available The purpose of this investigation was to determine lipid peroxidation markers, physiological stress and muscle damage in elite kayakers in response to a maximum 4-min kayak ergometer test (KE test, and possible correlations with individual 1000m kayaking performances. The sample consisted of twenty-three adult male and nine adult female elite kayakers, with more than three years' experience in international events, who voluntarily took part in this study. The subjects performed a 10-min warm-up, followed by a 2-min passive interval, before starting the test itself, which consisted of a maximum 4-min work paddling on an ergometer; right after the end of the test, an 8 ml blood sample was collected for analysis. 72 hours after the test, all athletes took part in an official race, when then it was possible to check their performance in the on site K1 1000m test (P1000m. The results showed that all lipoproteins and hematological parameters tested presented a significant difference (p≤0.05 after exercise for both genders. In addition, parameters related to muscle damage such as lactate dehydrogenase (LDH and creatine kinase (CK presented significant differences after stress. Uric acid presented an inverse correlation with the performance (r = -0.76, while CK presented a positive correlation (r = 0.46 with it. Based on these results, it was possible to verify muscle damage and the level of oxidative stress caused by indoor training with specific ergometers for speed kayaking, highlighting the importance of analyzing and getting to know the physiological responses to this type of training, in order to provide information to coaches and optimize athletic performance.

  14. Laser induced photoreceptor damage and recovery in the high numerical aperture eye of the garter snake.

    Science.gov (United States)

    Zwick, H; Edsall, P; Stuck, B E; Wood, E; Elliott, R; Cheramie, R; Hacker, H

    2008-02-01

    The garter snake provides a unique model for in-vivo imaging of photoreceptor damage induced by laser retinal exposure. Laser thermal/mechanical retinal injury induced alterations in photoreceptor structure and leukocyte cellular behavior. Photoreceptors turned white, lost mode structure, and swelled; leukocyte activity was observed in the vicinity of photoreceptor cells. Non-thermal alterations were identified with a bio-tag for oxidative stress. Mechanisms of photoreceptor recovery and replacement were observed and evaluated for active cytoskeletal systems by using an anti-actin tag that could detect the presence of active cytoskeletal systems resident in photoreceptors as well as other retinal systems.

  15. Radiation effects and damage formation in semiconductors due to high-energy ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kamarou, A.

    2006-11-07

    The object of this thesis was the study of ion-beam induced damage formation and annealing in crystalline and conventionally predamaged Ge, GaAs, and InP. The samples were irradiated either at {approx}80 K or at room temperature with Kr, Xe, or Au ions with specific energy of about 0.3 MeV/u to 3 MeV/u. Thereafter the samples were studied by means of Rutherford backscattering spectroscopy and/or transmission electron microscopy.

  16. Micropatterned comet assay enables high throughput and sensitive DNA damage quantification.

    Science.gov (United States)

    Ge, Jing; Chow, Danielle N; Fessler, Jessica L; Weingeist, David M; Wood, David K; Engelward, Bevin P

    2015-01-01

    The single cell gel electrophoresis assay, also known as the comet assay, is a versatile method for measuring many classes of DNA damage, including base damage, abasic sites, single strand breaks and double strand breaks. However, limited throughput and difficulties with reproducibility have limited its utility, particularly for clinical and epidemiological studies. To address these limitations, we created a microarray comet assay. The use of a micrometer scale array of cells increases the number of analysable comets per square centimetre and enables automated imaging and analysis. In addition, the platform is compatible with standard 24- and 96-well plate formats. Here, we have assessed the consistency and sensitivity of the microarray comet assay. We showed that the linear detection range for H2O2-induced DNA damage in human lymphoblastoid cells is between 30 and 100 μM, and that within this range, inter-sample coefficient of variance was between 5 and 10%. Importantly, only 20 comets were required to detect a statistically significant induction of DNA damage for doses within the linear range. We also evaluated sample-to-sample and experiment-to-experiment variation and found that for both conditions, the coefficient of variation was lower than what has been reported for the traditional comet assay. Finally, we also show that the assay can be performed using a 4× objective (rather than the standard 10× objective for the traditional assay). This adjustment combined with the microarray format makes it possible to capture more than 50 analysable comets in a single image, which can then be automatically analysed using in-house software. Overall, throughput is increased more than 100-fold compared to the traditional assay. Together, the results presented here demonstrate key advances in comet assay technology that improve the throughput, sensitivity, and robustness, thus enabling larger scale clinical and epidemiological studies. © The Author 2014. Published by

  17. Radiation effects and damage formation in semiconductors due to high-energy ion irradiation

    International Nuclear Information System (INIS)

    Kamarou, A.

    2006-01-01

    The object of this thesis was the study of ion-beam induced damage formation and annealing in crystalline and conventionally predamaged Ge, GaAs, and InP. The samples were irradiated either at ∼80 K or at room temperature with Kr, Xe, or Au ions with specific energy of about 0.3 MeV/u to 3 MeV/u. Thereafter the samples were studied by means of Rutherford backscattering spectroscopy and/or transmission electron microscopy

  18. Behavior of high resistance to He{sup 2+} induced irradiation damage in metallic glass

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bin [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Mei, Xianxiu, E-mail: xxmei@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Hou, Wenjing; Wang, Younian [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Wang, Zhiguang [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Dong, Chuang [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China)

    2013-10-01

    Highlights: •Metallic glasses and W were irradiated with 500 keV He{sup 2+} at different fluences. •Metallic glasses could maintain amorphous state at different irradiation fluences. •The resistance to He{sup 2+} irradiation of metallic glasses was superior to the one in W metal. •Cu- and Zr-based metallic glasses had better resistance to He{sup 2+} irradiation. -- Abstract: This study details the irradiation of various metallic glasses ((Cu{sub 47}Zr{sub 45}Al{sub 8}){sub 98.5}Y{sub 1.5}, Zr{sub 64}Cu{sub 17.8}Ni{sub 10.7}Al{sub 7.5}, Co{sub 61.2}B{sub 26.2}Si{sub 7.8}Ta{sub 4.8}) and metallic W using He{sup 2+} ions with an energy of 500 keV at irradiation fluences of 2 × 10{sup 17}, 1 × 10{sup 18} and 2 × 10{sup 18} ions/cm{sup 2} to investigate the radiation-resistant properties of these metallic glasses compared to the conventional irradiation-resistant material W. These three metallic glasses were able to maintain an amorphous state during these irradiation fluences. There was no significant irradiation damage at the low irradiation fluence. When the irradiation fluence was increased to 2 × 10{sup 18} ions/cm{sup 2}, a damage layer appeared up to a distance corresponding to the range of the ions away from the surfaces of the Cu- and Zr-based metallic glasses without any visible damage on the surface. Significant surface stripping damage appeared in the Co-based metallic glass. Relatively speaking, surface layer peeling appeared in metallic W along the crystal boundary at a fluence of 1 × 10{sup 18} ions/cm{sup 2}. When the fluence was increased to 2 × 10{sup 18} ions/cm{sup 2}, multilayer peeling, stripping, etc. appeared. The roughness of the Cu- and Zr-based metallic glass showed further smoothing with increasing fluence, while the opposite occurred in the Co-based metallic glass. Within the wavelength range of 400–1700 nm, after irradiation of He{sup 2+} at a fluence of 1 × 10{sup 18} ions/cm{sup 2}, the reflectance of the Cu-based and Co

  19. The DNA damage of high doses of X-ray on human peripheral blood nucleated cell's and sperm

    International Nuclear Information System (INIS)

    Wang Hui; Zoulian; Jiang Qisheng; Li Fengsheng; He Rui; Song Xiujun

    2011-01-01

    Objective: To detect the DNA damage of high doses of X-ray on human peripheral blood nucleated cell's and sperm by single cell gel electrophoresis (SCGE). Evaluation the level of DNA damage of human peripheral blood nucleated cell's and sperm after high doses of X-ray. Methods: Using human peripheral blood with normal blood routine and normal sperm,give the dose of 0 Gy, 2 Gy, 4 Gy, 6 Gy, 8 Gy, 10 Gy X-ray radiation with energy of 6MU. Detect the percentage of comet-like tail, tail length and content of DNA in tail of whole blood cell's DNA and sperm's DNA by SCGE technique in 1 hour. Results: The peripheral blood nucleated cell's and sperm's comet rate were 1.00±0.10%, 2.1±1.5%, respectively, have an evidently variance in 0 Gy group (υ=18, t=2.31>1.734, P 1.734, P 1.734, P<0.05). The peripheral blood nucleated cell's and sperm's comet rate were all 100%, 100%, have no-statistical significance in 8 Gy, 10 Gy group. Conclusion: The evidence is powerful enough. That the sperm's SCGE is more sensitive than peripheral blood nucleated cell's SCGE in reflect the X-ray damage in a certain extent (2-6 Gy). (authors)

  20. Highly transparent, stable, and superhydrophobic coatings based on gradient structure design and fast regeneration from physical damage

    International Nuclear Information System (INIS)

    Chen, Zao; Liu, Xiaojiang; Wang, Yan; Li, Jun; Guan, Zisheng

    2015-01-01

    Graphical abstract: - Highlights: • Highly transparent, stable, and superhydrophobic PET film was fabricated by dip-coating way. • The gradient structure is beneficial to both hydrophobicity and transparency. • The superhydrophobic PET film after physical damage can quickly regain by one-step spary. • The fabrication method is available for various substrates and large-scale production. - Abstract: Optical transparency, mechanical flexibility, and fast regeneration are important factors to expand the application of superhydrophobic surfaces. Herein, we fabricated highly transparent, stable, and superhydrophobic coatings through a novel gradient structure design by versatile dip-coating of silica colloid particles (SCPs) and diethoxydimethysiliane cross-linked silica nanoparticles (DDS-SNPs) on polyethylene terephthalate (PET) film and glass, followed by the modification of octadecyltrichlorosiliane (OTCS). When the DDS concentration reached 5 wt%, the modified SCPs/DDS-SNPs coating exhibited a water contact angle (WCA) of 153° and a sliding angle (SA) <5°. Besides, the average transmittance of this superhydrophobic coating on PET film and glass was increased by 2.7% and 1% in the visible wavelength, respectively. This superhydrophobic coating also showed good robustness and stability against water dropping impact, ultrasonic damage, and acid solution. Moreover, the superhydrophobic PET film after physical damage can quickly regain the superhydrophobicity by one-step spray regenerative solution of dodecyltrichlorosilane (DTCS) modified silica nanoparticles at room temperature. The demonstrated method for the preparation and regeneration of superhydrophobic coating is available for different substrates and large-scale production at room temperature.

  1. Diamond Particle Detector Properties during High Fluence Material Damage Tests and their Future Applications for Machine Protection in the LHC

    CERN Document Server

    Burkart, F; Borburgh, J; Dehning, B; Di Castro, M; Griesmayer, E; Lechner, A; Lendaro, J; Loprete, F; Losito, R; Montesano, S; Schmidt, R; Wollmann, D; Zerlauth, M

    2013-01-01

    Experience with LHC machine protection (MP) during the last three years of operation shows that the MP systems sufficiently protect the LHC against damage in case of failures leading to beam losses with a time constant exceeding 1ms. An unexpected fast beam loss mechanism, called UFOs [1], was observed, which could potentially quench superconducting magnets. For such fast losses, but also for better understanding of slower losses, an improved understanding of the loss distribution within a bunch train is required [2]. Diamond particle detectors with bunch-by-bunch resolution and high dynamic range have been developed and successfully tested in the LHC and in experiments to quantify the damage limits of LHC components. This paper will focus on experience gained in use of diamond detectors. The properties of these detectors were measured during high-fluence material damage tests in CERN’s Hi-RadMat facility. The results will be discussed and compared to the cross-calibration with FLUKA simulations. Future app...

  2. Effects of deposition rates on laser damage threshold of TiO2/SiO2 high reflectors

    International Nuclear Information System (INIS)

    Yao Jianke; Xu Cheng; Ma Jianyong; Fang Ming; Fan Zhengxiu; Jin Yunxia; Zhao Yuanan; He Hongbo; Shao Jianda

    2009-01-01

    TiO 2 single layers and TiO 2 /SiO 2 high reflectors (HR) are prepared by electron beam evaporation at different TiO 2 deposition rates. It is found that the changes of properties of TiO 2 films with the increase of rate, such as the increase of refractive index and extinction coefficient and the decrease of physical thickness, lead to the spectrum shift and reflectivity bandwidth broadening of HR together with the increase of absorption and decrease of laser-induced damage threshold. The damages are found of different morphologies: a shallow pit to a seriously delaminated and deep crater, and the different amorphous-to-anatase-to-rutile phase transition processes detected by Raman study. The frequency shift of Raman vibration mode correlates with the strain in film. Energy dispersive X-ray analysis reveals that impurities and non-stoichiometric defects are two absorption initiations resulting to the laser-induced transformation.

  3. Mitigation technologies for damage induced by pressure waves in high-power mercury spallation neutron sources (1). Material surface improvement

    International Nuclear Information System (INIS)

    Naoe, Takashi; Futakawa, Masatoshi; Wakui, Takashi; Kogawa, Hiroyuki; Shoubu, Takahisa; Takeuchi, Hirotsugu; Kawai, Masayoshi

    2008-01-01

    Liquid-mercury target systems for MW-class spallation neutron sources are being developed in the world. Proton beams will be used to induce the spallation reaction. At the moment the proton beam hits the target, pressure waves are generated in the mercury because of the abrupt heat deposition. The pressure waves interact with the target vessel leading to negative pressure that may cause cavitation along the vessel wall. Localized impacts by microjets and/or shock waves that are caused by cavitation bubble collapse impose pitting damage on the vessel wall. Bubble collapse behavior was observed by using a high-speed video camera, as well as simulated numerically. Localized impact due to cavitation bubble collapse was quantitatively estimated through comparison between numerical simulation and experiment. A novel surface treatment technique that consists of carburizing and nitriding processes was developed and the treatment condition was optimized to mitigate the pitting damage due to localized impacts. (author)

  4. High strain rate and quasi-static tensile behaviour of Ti-6Al-4V after cyclic damage

    Directory of Open Access Journals (Sweden)

    Verleysen P.

    2012-08-01

    Full Text Available It is common that energy absorbing structural elements are subjected to a number of loading cycles before a crash event. Several studies have shown that previous fatigue can significantly influence the tensile properties of some materials, and hence the behaviour of structural elements made of them. However, when the capacity of absorbing energy of engineering materials is determined, fresh material without any fatigue damage is most often used. This study investigates the effect of fatigue damage on the dynamic tensile properties of Ti-6Al-4V in thin-sheet form. Results are completed with tests at quasi-static strain rates and observations of the fracture surfaces, and compared with results obtained from other alloys and steel grades. The experiments show that the dynamic properties of Ti-6Al-4V are not affected by a number of fatigue loading cycles high enough to significantly reduce the energy absorbing capabilities of EDM machined samples.

  5. High activity antioxidant enzymes protect flying-fox haemoglobin against damage: an evolutionary adaptation for flight?

    Science.gov (United States)

    Reinke, N B; O'Brien, G M

    2006-11-01

    Flying-foxes are better able to defend haemoglobin against autoxidation than non-volant mammals such as sheep. When challenged with the common physiological oxidant, hydrogen peroxide, haemolysates of flying-fox red blood cells (RBC) were far less susceptible to methaemoglobin formation than sheep. Challenge with 1-acetyl-2-phenylhydrazine (APH) caused only half as much methaemoglobin formation in flying-fox as in ovine haemolysates. When intact cells were challenged with phenazine methosulfate (PMS), flying-fox RBC partially reversed the oxidant damage, and reduced methaemoglobin from 40 to 20% over 2 h incubation, while ovine methaemoglobin remained at 40%. This reflected flying-fox cells' capacity to replenish GSH fast enough that it did not deplete beyond 50%, while ovine RBC GSH was depleted to around 20%. The greater capacity of flying-foxes to defend haemoglobin against oxidant damage may be explained in part by antioxidant enzymes catalase, superoxide dismutase and cytochrome-b ( 5 ) reductase having two- to four-fold higher activity than in sheep (P foxes.

  6. High-flux He+ irradiation effects on surface damages of tungsten under ITER relevant conditions

    International Nuclear Information System (INIS)

    Liu, Lu; Liu, Dongping; Hong, Yi; Fan, Hongyu; Ni, Weiyuan; Yang, Qi; Bi, Zhenhua; Benstetter, Günther; Li, Shouzhe

    2016-01-01

    A large-power inductively coupled plasma source was designed to perform the continuous helium ions (He + ) irradiations of polycrystalline tungsten (W) under International Thermonuclear Experimental Reactor (ITER) relevant conditions. He + irradiations were performed at He + fluxes of 2.3 × 10 21 –1.6 × 10 22 /m 2  s and He + energies of 12–220 eV. Surface damages and microstructures of irradiated W were observed by scanning electron microscopy. This study showed the growth of nano-fuzzes with their lengths of 1.3–2.0 μm at He + energies of >70 eV or He + fluxes of >1.3 × 10 22 /m 2  s. Nanometer-sized defects or columnar microstructures were formed in W surface layer due to low-energy He + irradiations at an elevated temperature (>1300 K). The diffusion and coalescence of He atoms in W surface layers led to the growth and structures of nano-fuzzes. This study indicated that a reduction of He + energy below 12–30 eV may greatly decrease the surface damage of tungsten diverter in the fusion reactor.

  7. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    International Nuclear Information System (INIS)

    Renis, M.; Malfa, G.; Tomasello, B.; Borghesi, M.; Schettino, G.; Favetta, M.; Romano, F.; Cirrone, G. A. P.; Manti, L.

    2013-01-01

    Studies regarding the radiobiological effects of low dose radiation, microbeam irradiation services have been developed in the world and today laser acceleration of protons and heavy ions may be used in radiation therapy. The application of different facilities is essential for studying bystander effects and relating signalling phenomena in different cells or tissues. In particular the use of ion beams results advantageous in cancer radiotherapy compared to more commonly used X-rays, since the ability of ions in delivering lethal amount of doses into the target tumour avoiding or limiting damage to the contiguous healthy tissues. At the INFN-LNS in Catania, a multidisciplinary radiobiology group is strategically structured aimed to develop radiobiological research, finalised to therapeutic applications, compatible with the use of high dose laser-driven ion beams. The characteristic non-continuous dose rates with several orders of magnitude of laser-driven ion beams makes this facility very interesting in the cellular systems' response to ultra-high dose rates with non-conventional pulse time intervals cellular studies. Our group have projected to examine the effect of high dose laser-driven ion beams on two cellular types: foetal fibroblasts (normal control cells) and DU145 (prostate cancer cells), studying the modulation of some different bio-molecular parameters, in particular cell proliferation and viability, DNA damage, redox cellular status, morphological alterations of both the cytoskeleton components and some cell organelles and the possible presence of apoptotic or necrotic cell death. Our group performed preliminary experiments with high energy (60 MeV), dose rate of 10 Gy/min, doses of 1, 2, 3 Gy and LET 1 keV/μm on human foetal fibroblasts (control cells). We observed that cell viability was not influenced by the characteristics of the beam, the irradiation conditions or the analysis time. Conversely, DNA damage was present at time 0, immediately

  8. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Renis, M.; Malfa, G.; Tomasello, B. [Drug Sciences Department, University of Catania, Catania (Italy); Borghesi, M.; Schettino, G. [Queen' s University Belfast, Northern Ireland (United Kingdom); Favetta, M.; Romano, F.; Cirrone, G. A. P. [National Institute for Nuclear Physics (INFN-LNS), Catania (Italy); Manti, L. [Physics Science Department, University of Naples Federico II, Naples, and National Institute for Nuclear Physics (INFN), Naples (Italy)

    2013-07-26

    Studies regarding the radiobiological effects of low dose radiation, microbeam irradiation services have been developed in the world and today laser acceleration of protons and heavy ions may be used in radiation therapy. The application of different facilities is essential for studying bystander effects and relating signalling phenomena in different cells or tissues. In particular the use of ion beams results advantageous in cancer radiotherapy compared to more commonly used X-rays, since the ability of ions in delivering lethal amount of doses into the target tumour avoiding or limiting damage to the contiguous healthy tissues. At the INFN-LNS in Catania, a multidisciplinary radiobiology group is strategically structured aimed to develop radiobiological research, finalised to therapeutic applications, compatible with the use of high dose laser-driven ion beams. The characteristic non-continuous dose rates with several orders of magnitude of laser-driven ion beams makes this facility very interesting in the cellular systems' response to ultra-high dose rates with non-conventional pulse time intervals cellular studies. Our group have projected to examine the effect of high dose laser-driven ion beams on two cellular types: foetal fibroblasts (normal control cells) and DU145 (prostate cancer cells), studying the modulation of some different bio-molecular parameters, in particular cell proliferation and viability, DNA damage, redox cellular status, morphological alterations of both the cytoskeleton components and some cell organelles and the possible presence of apoptotic or necrotic cell death. Our group performed preliminary experiments with high energy (60 MeV), dose rate of 10 Gy/min, doses of 1, 2, 3 Gy and LET 1 keV/μm on human foetal fibroblasts (control cells). We observed that cell viability was not influenced by the characteristics of the beam, the irradiation conditions or the analysis time. Conversely, DNA damage was present at time 0, immediately

  9. Use of enzymes to minimize the rheological dough problems caused by high levels of damaged starch in starch-gluten systems.

    Science.gov (United States)

    Barrera, Gabriela N; León, Alberto E; Ribotta, Pablo D

    2016-05-01

    During wheat milling, starch granules can experience mechanical damage, producing damaged starch. High levels of damaged starch modify the physicochemical properties of wheat flour, negatively affecting the dough behavior as well as the flour quality and cookie and bread making quality. The aim of this work was to evaluate the effect of α-amylase, maltogenic amylase and amyloglucosidase on dough rheology in order to propose alternatives to reduce the issues related to high levels of damaged starch. The dough with a high level of damaged starch became more viscous and resistant to deformations as well as less elastic and extensible. The soluble fraction of the doughs influenced the rheological behavior of the systems. The α-amylase and amyloglucosidase reduced the negative effects of high damaged starch contents, improving the dough rheological properties modified by damaged starch. The rheological behavior of dough with the higher damaged-starch content was related to a more open gluten network arrangement as a result of the large size of the swollen damaged starch granules. We can conclude that the dough rheological properties of systems with high damaged starch content changed positively as a result of enzyme action, particularly α-amylase and amyloglucosidase additions, allowing the use of these amylases and mixtures of them as corrective additives. Little information was reported about amyloglucosidase activity alone or combined with α-amylase. The combinations of these two enzymes are promising to minimize the negative effects caused by high levels of damaged starch on product quality. More research needs to be done on bread quality combining these two enzymes. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  10. The co-evolution of microstructure features in self-ion irradiated HT9 at very high damage levels

    Energy Technology Data Exchange (ETDEWEB)

    Getto, E., E-mail: getto@usna.edu [Department of Mechanical Engineering, United States Naval Academy, Annapolis, MD, 21402 (United States); Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI, 48109 (United States); Vancoevering, G.; Was, G.S. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI, 48109 (United States)

    2017-02-15

    Understanding the void swelling and phase evolution of reactor structural materials at very high damage levels is essential to maintaining safety and longevity of components in Gen IV fast reactors. A combination of ion irradiation and modeling was utilized to understand the microstructure evolution of ferritic-martensitic alloy HT9 at high dpa. Self-ion irradiation experiments were performed on alloy HT9 to determine the co-evolution of voids, dislocations and precipitates up to 650 dpa at 460 °C. Modeling of microstructure evolution was conducted using the modified Radiation Induced Microstructure Evolution (RIME) model, which utilizes a mean field rate theory approach with grouped cluster dynamics. Irradiations were performed with 5 MeV raster-scanned Fe{sup 2+} ions on samples pre-implanted with 10 atom parts per million He. The swelling, dislocation and precipitate evolution at very high dpa was determined using Analytical Electron Microscopy in Scanning Transmission Electron Microscopy (STEM) mode. Experimental results were then interpreted using the RIME model. A microstructure consisting only of dislocations and voids is insufficient to account for the swelling evolution observed experimentally at high damage levels in a complicated microstructure such as irradiated alloy HT9. G phase was found to have a minimal effect on either void or dislocation evolution. M{sub 2}X played two roles; a variable biased sink for defects, and as a vehicle for removal of carbon from solution, thus promoting void growth. When accounting for all microstructure interactions, swelling at high damage levels is a dynamic process that continues to respond to other changes in the microstructure as long as they occur.

  11. Additive manufactured serialization

    Science.gov (United States)

    Bobbitt, III, John T.

    2017-04-18

    Methods for forming an identifying mark in a structure are described. The method is used in conjunction with an additive manufacturing method and includes the alteration of a process parameter during the manufacturing process. The method can form in a unique identifying mark within or on the surface of a structure that is virtually impossible to be replicated. Methods can provide a high level of confidence that the identifying mark will remain unaltered on the formed structure.

  12. Highly reliable field electron emitters produced from reproducible damage-free carbon nanotube composite pastes with optimal inorganic fillers

    Science.gov (United States)

    Kim, Jae-Woo; Jeong, Jin-Woo; Kang, Jun-Tae; Choi, Sungyoul; Ahn, Seungjoon; Song, Yoon-Ho

    2014-02-01

    Highly reliable field electron emitters were developed using a formulation for reproducible damage-free carbon nanotube (CNT) composite pastes with optimal inorganic fillers and a ball-milling method. We carefully controlled the ball-milling sequence and time to avoid any damage to the CNTs, which incorporated fillers that were fully dispersed as paste constituents. The field electron emitters fabricated by printing the CNT pastes were found to exhibit almost perfect adhesion of the CNT emitters to the cathode, along with good uniformity and reproducibility. A high field enhancement factor of around 10 000 was achieved from the CNT field emitters developed. By selecting nano-sized metal alloys and oxides and using the same formulation sequence, we also developed reliable field emitters that could survive high-temperature post processing. These field emitters had high durability to post vacuum annealing at 950 °C, guaranteeing survival of the brazing process used in the sealing of field emission x-ray tubes. We evaluated the field emitters in a triode configuration in the harsh environment of a tiny vacuum-sealed vessel and observed very reliable operation for 30 h at a high current density of 350 mA cm-2. The CNT pastes and related field emitters that were developed could be usefully applied in reliable field emission devices.

  13. Large-strain time-temperature equivalence in high density polyethylene for prediction of extreme deformation and damage

    Directory of Open Access Journals (Sweden)

    Gray G.T.

    2012-08-01

    Full Text Available Time-temperature equivalence is a widely recognized property of many time-dependent material systems, where there is a clear predictive link relating the deformation response at a nominal temperature and a high strain-rate to an equivalent response at a depressed temperature and nominal strain-rate. It has been found that high-density polyethylene (HDPE obeys a linear empirical formulation relating test temperature and strain-rate. This observation was extended to continuous stress-strain curves, such that material response measured in a load frame at large strains and low strain-rates (at depressed temperatures could be translated into a temperature-dependent response at high strain-rates and validated against Taylor impact results. Time-temperature equivalence was used in conjuction with jump-rate compression tests to investigate isothermal response at high strain-rate while exluding adiabatic heating. The validated constitutive response was then applied to the analysis of Dynamic-Tensile-Extrusion of HDPE, a tensile analog to Taylor impact developed at LANL. The Dyn-Ten-Ext test results and FEA found that HDPE deformed smoothly after exiting the die, and after substantial drawing appeared to undergo a pressure-dependent shear damage mechanism at intermediate velocities, while it fragmented at high velocities. Dynamic-Tensile-Extrusion, properly coupled with a validated constitutive model, can successfully probe extreme tensile deformation and damage of polymers.

  14. Optical Fiber Demodulation System with High Performance for Assessing Fretting Damage of Steam Generator Tubes.

    Science.gov (United States)

    Huang, Peijian; Wang, Ning; Li, Junying; Zhu, Yong; Zhang, Jie; Xi, Zhide

    2018-01-12

    In order to access the fretting damage of the steam generator tube (SGT), a fast fiber Fabry-Perot (F-P) non-scanning correlation demodulation system based on a super luminescent light emitting diode (SLED) was performed. By demodulating the light signal coming out from the F-P force sensor, the radial collision force between the SGT and the tube support plate (TSP) was interrogated. For higher demodulation accuracy, the effects of the center wavelength, bandwidth, and spectrum noise of SLED were discussed in detail. Specially, a piezoelectric ceramic transducer (PZT) modulation method was developed to get rid of the interference of mode coupling induced by different types of fiber optics in the demodulation system. The reflectivity of optical wedge and F-P sensor was optimized. Finally, the demodulation system worked well in a 1:1 steam generator test loop and successfully demodulated a force signal of 32 N with a collision time of 2 ms.

  15. Damage induced by high energy multiply charged oxygen ions in oxide coated silicon

    Energy Technology Data Exchange (ETDEWEB)

    Dhole, S.D. [Department of Physics, University of Pune, Pune 411 007 (India)]. E-mail: sanjay@physics.unipune.ernet.in; Dahiwale, S.S. [Department of Physics, University of Pune, Pune 411 007 (India); Kulkarni, V.R. [Department of Physics, University of Pune, Pune 411 007 (India); Bogle, K.A. [Department of Physics, University of Pune, Pune 411 007 (India); Shinde, N.S. [Ecotopia Science Institute, Division of Energy Science, Nagoya University, Nagoya (Japan); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411 007 (India)

    2006-03-15

    P-type oxide coated silicon samples of resistivity 120 {omega} cm were irradiated with 60 MeV oxygen ions of fixed charge states 4{sup +}, 5{sup +}, 6{sup +} and 7{sup +} at an equal fluence of, {phi}, {approx}10{sup 13} ions/cm{sup 2}. The induced damage was estimated by Hall voltage, Hall coefficient, carrier concentration and lifetime of minority carriers. The results indicate that Hall voltage (V {sub H}) and Hall coefficient (R {sub H}) increases, while carrier concentration (n) decreases with the charge state of impinging oxygen ions. The V {sub H} increases from 22 mV to 76.5 mV at typical current of 0.5 mA, R {sub H} from 0.42 x 10{sup 5} cm{sup 3}/C to 2.16 x 10{sup 5} cm{sup 3}/C and n decreases from 9 x 10{sup 13} cm{sup -3} to 2.88 x 10{sup 13} cm{sup -3} for the different charge states. This fact is an evidence that the oxygen ions with an individual fixed charge state passing through very thin 40 A layer of silicon dioxide, induces significant damage at the SiO{sub 2}-Si interface through the mechanism of electronic stopping power. The lifetime of minority charge carriers, {tau} (bulk property), remains constant at around 6 {mu}s for all the charge states of the 60 MeV energy oxygen ion irradiated samples at a constant fluence of, {phi}, 10{sup 13} ions/cm{sup 2}.

  16. DNA damage in buccal mucosa cells of pre-school children exposed to high levels of urban air pollutants.

    Directory of Open Access Journals (Sweden)

    Elisabetta Ceretti

    Full Text Available Air pollution has been recognized as a human carcinogen. Children living in urban areas are a high-risk group, because genetic damage occurring early in life is considered able to increase the risk of carcinogenesis in adulthood. This study aimed to investigate micronuclei (MN frequency, as a biomarker of DNA damage, in exfoliated buccal cells of pre-school children living in a town with high levels of air pollution. A sample of healthy 3-6-year-old children living in Brescia, Northern Italy, was investigated. A sample of the children's buccal mucosa cells was collected during the winter months in 2012 and 2013. DNA damage was investigated using the MN test. Children's exposure to urban air pollution was evaluated by means of a questionnaire filled in by their parents that included items on various possible sources of indoor and outdoor pollution, and the concentration of fine particulate matter (PM10, PM2.5 and NO2 in the 1-3 weeks preceding biological sample collection. 181 children (mean age ± SD: 4.3 ± 0.9 years were investigated. The mean ± SD MN frequency was 0.29 ± 0.13%. A weak, though statistically significant, association of MN with concentration of air pollutants (PM10, PM2.5 and NO2 was found, whereas no association was apparent between MN frequency and the indoor and outdoor exposure variables investigated via the questionnaire. This study showed a high MN frequency in children living in a town with heavy air pollution in winter, higher than usually found among children living in areas with low or medium-high levels of air pollution.

  17. High performance, rapid thermal/UV curing epoxy resin for additive manufacturing of short and continuous carbon fiber epoxy composites

    Science.gov (United States)

    Lewicki, James

    2018-04-17

    An additive manufacturing resin system including an additive manufacturing print head; a continuous carbon fiber or short carbon fibers operatively connected to the additive manufacturing print head; and a tailored resin operatively connected to the print head, wherein the tailored resin has a resin mass and wherein the tailored resin includes an epoxy component, a filler component, a catalyst component, and a chain extender component; wherein the epoxy component is 70-95% of the resin mass, wherein the filler component is 1-20% of the resin mass, wherein the catalyst component is 0.1-10% of the resin mass, and wherein the chain extender component is 0-50% of the resin mass.

  18. High Volume Manufacturing of Silicon-Film Solar Cells and Modules; Final Subcontract Report, 26 February 2003 - 30 September 2003

    Energy Technology Data Exchange (ETDEWEB)

    Rand, J. A.; Culik, J. S.

    2005-10-01

    The objective of the PV Manufacturing R&D subcontract was to continue to improve AstroPower's technology for manufacturing Silicon-Film* wafers, solar cells, and modules to reduce costs, and increase production yield, throughput, and capacity. As part of the effort, new technology such as the continuous back metallization screen-printing system and the laser scribing system were developed and implemented. Existing processes, such as the silicon nitride antireflection coating system and the fire-through process were optimized. Improvements were made to the statistical process control (SPC) systems of the major manufacturing processes: feedstock preparation, wafer growth, surface etch, diffusion, and the antireflection coating process. These process improvements and improved process control have led to an increase of 5% relative power, and nearly 15% relative improvement in mechanical and visual yield.

  19. Mechanism of cluster DNA damage repair in response to high-atomic number and energy particles radiation

    Energy Technology Data Exchange (ETDEWEB)

    Asaithamby, Aroumougame, E-mail: Aroumougame.Asaithamy@UTsouthwestern.edu [Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390 (United States); Chen, David J., E-mail: David.Chen@UTsouthwestern.edu [Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390 (United States)

    2011-06-03

    Low-linear energy transfer (LET) radiation (i.e., {gamma}- and X-rays) induces DNA double-strand breaks (DSBs) that are rapidly repaired (rejoined). In contrast, DNA damage induced by the dense ionizing track of high-atomic number and energy (HZE) particles is slowly repaired or is irreparable. These unrepaired and/or misrepaired DNA lesions may contribute to the observed higher relative biological effectiveness for cell killing, chromosomal aberrations, mutagenesis, and carcinogenesis in HZE particle irradiated cells compared to those treated with low-LET radiation. The types of DNA lesions induced by HZE particles have been characterized in vitro and usually consist of two or more closely spaced strand breaks, abasic sites, or oxidized bases on opposing strands. It is unclear why these lesions are difficult to repair. In this review, we highlight the potential of a new technology allowing direct visualization of different types of DNA lesions in human cells and document the emerging significance of live-cell imaging for elucidation of the spatio-temporal characterization of complex DNA damage. We focus on the recent insights into the molecular pathways that participate in the repair of HZE particle-induced DSBs. We also discuss recent advances in our understanding of how different end-processing nucleases aid in repair of DSBs with complicated ends generated by HZE particles. Understanding the mechanism underlying the repair of DNA damage induced by HZE particles will have important implications for estimating the risks to human health associated with HZE particle exposure.

  20. Mechanism of cluster DNA damage repair in response to high-atomic number and energy particles radiation

    International Nuclear Information System (INIS)

    Asaithamby, Aroumougame; Chen, David J.

    2011-01-01

    Low-linear energy transfer (LET) radiation (i.e., γ- and X-rays) induces DNA double-strand breaks (DSBs) that are rapidly repaired (rejoined). In contrast, DNA damage induced by the dense ionizing track of high-atomic number and energy (HZE) particles is slowly repaired or is irreparable. These unrepaired and/or misrepaired DNA lesions may contribute to the observed higher relative biological effectiveness for cell killing, chromosomal aberrations, mutagenesis, and carcinogenesis in HZE particle irradiated cells compared to those treated with low-LET radiation. The types of DNA lesions induced by HZE particles have been characterized in vitro and usually consist of two or more closely spaced strand breaks, abasic sites, or oxidized bases on opposing strands. It is unclear why these lesions are difficult to repair. In this review, we highlight the potential of a new technology allowing direct visualization of different types of DNA lesions in human cells and document the emerging significance of live-cell imaging for elucidation of the spatio-temporal characterization of complex DNA damage. We focus on the recent insights into the molecular pathways that participate in the repair of HZE particle-induced DSBs. We also discuss recent advances in our understanding of how different end-processing nucleases aid in repair of DSBs with complicated ends generated by HZE particles. Understanding the mechanism underlying the repair of DNA damage induced by HZE particles will have important implications for estimating the risks to human health associated with HZE particle exposure.

  1. Emergence of realism: Enhanced visual artistry and high accuracy of visual numerosity representation after left prefrontal damage.

    Science.gov (United States)

    Takahata, Keisuke; Saito, Fumie; Muramatsu, Taro; Yamada, Makiko; Shirahase, Joichiro; Tabuchi, Hajime; Suhara, Tetsuya; Mimura, Masaru; Kato, Motoichiro

    2014-05-01

    Over the last two decades, evidence of enhancement of drawing and painting skills due to focal prefrontal damage has accumulated. It is of special interest that most artworks created by such patients were highly realistic ones, but the mechanism underlying this phenomenon remains to be understood. Our hypothesis is that enhanced tendency of realism was associated with accuracy of visual numerosity representation, which has been shown to be mediated predominantly by right parietal functions. Here, we report a case of left prefrontal stroke, where the patient showed enhancement of artistic skills of realistic painting after the onset of brain damage. We investigated cognitive, functional and esthetic characteristics of the patient׳s visual artistry and visual numerosity representation. Neuropsychological tests revealed impaired executive function after the stroke. Despite that, the patient׳s visual artistry related to realism was rather promoted across the onset of brain damage as demonstrated by blind evaluation of the paintings by professional art reviewers. On visual numerical cognition tasks, the patient showed higher performance in comparison with age-matched healthy controls. These results paralleled increased perfusion in the right parietal cortex including the precuneus and intraparietal sulcus. Our data provide new insight into mechanisms underlying change in artistic style due to focal prefrontal lesion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Multiscale analysis: a way to investigate laser damage precursors in materials for high power applications at nanosecond pulse duration

    Science.gov (United States)

    Natoli, J. Y.; Wagner, F.; Ciapponi, A.; Capoulade, J.; Gallais, L.; Commandré, M.

    2010-11-01

    The mechanism of laser induced damage in optical materials under high power nanosecond laser irradiation is commonly attributed to the presence of precursor centers. Depending on material and laser source, the precursors could have different origins. Some of them are clearly extrinsic, such as impurities or structural defects linked to the fabrication conditions. In most cases the center size ranging from sub-micrometer to nanometer scale does not permit an easy detection by optical techniques before irradiation. Most often, only a post mortem observation of optics permits to proof the local origin of breakdown. Multi-scale analyzes by changing irradiation beam size have been performed to investigate the density, size and nature of laser damage precursors. Destructive methods such as raster scan, laser damage probability plot and morphology studies permit to deduce the precursor densities. Another experimental way to get information on nature of precursors is to use non destructive methods such as photoluminescence and absorption measurements. The destructive and non destructive multiscale studies are also motivated for practical reasons. Indeed LIDT studies of large optics as those used in LMJ or NIF projects are commonly performed on small samples and with table top lasers whose characteristics change from one to another. In these conditions, it is necessary to know exactly the influence of the different experimental parameters and overall the spot size effect on the final data. In this paper, we present recent developments in multiscale characterization and results obtained on optical coatings (surface case) and KDP crystal (bulk case).

  3. High-resolution measurement of the unsteady velocity field to evaluate blood damage induced by a mechanical heart valve.

    Science.gov (United States)

    Bellofiore, Alessandro; Quinlan, Nathan J

    2011-09-01

    We investigate the potential of prosthetic heart valves to generate abnormal flow and stress patterns, which can contribute to platelet activation and lysis according to blood damage accumulation mechanisms. High-resolution velocity measurements of the unsteady flow field, obtained with a standard particle image velocimetry system and a scaled-up model valve, are used to estimate the shear stresses arising downstream of the valve, accounting for flow features at scales less than one order of magnitude larger than blood cells. Velocity data at effective spatial and temporal resolution of 60 μm and 1.75 kHz, respectively, enabled accurate extraction of Lagrangian trajectories and loading histories experienced by blood cells. Non-physiological stresses up to 10 Pa were detected, while the development of vortex flow in the wake of the valve was observed to significantly increase the exposure time, favouring platelet activation. The loading histories, combined with empirical models for blood damage, reveal that platelet activation and lysis are promoted at different stages of the heart cycle. Shear stress and blood damage estimates are shown to be sensitive to measurement resolution.

  4. Implementation of constitutive equations for creep damage mechanics into the ABAQUS finite element code - some practical cases in high temperature component design and life assessment

    International Nuclear Information System (INIS)

    Segle, P.; Samuelson, L.Aa.; Andersson, Peder; Moberg, F.

    1996-01-01

    Constitutive equations for creep damage mechanics are implemented into the finite element program ABAQUS using a user supplied subroutine, UMAT. A modified Kachanov-Rabotnov constitutive equation which accounts for inhomogeneity in creep damage is used. With a user defined material a number of bench mark tests are analyzed for verification. In the cases where analytical solutions exist, the numerical results agree very well. In other cases, the creep damage evolution response appear to be realistic in comparison with laboratory creep tests. The appropriateness of using the creep damage mechanics concept in design and life assessment of high temperature components is demonstrated. 18 refs

  5. LEAN Manufacturing

    DEFF Research Database (Denmark)

    Bilberg, Arne

    . The mission with the strategy is to obtain competitive production in Denmark and in Western Europe based on the right combination of manufacturing principles, motivated and trained employees, level of automation, and cooperation with suppliers and customers worldwide. The strategy has resulted in technical...

  6. High-sensitivity C-reactive protein predicts target organ damage in Chinese patients with metabolic syndrome

    DEFF Research Database (Denmark)

    Zhao, Zhigang; Nie, Hai; He, Hongbo

    2007-01-01

    with metabolic syndrome. A total of 1082 consecutive patients of Chinese origin were screened for the presence of metabolic syndrome according to the National Cholesterol Education Program's Adult Treatment Panel III. High-sensitivity C-reactive protein and target organ damage, including cardiac hypertrophy......Observational studies established high-sensitivity C-reactive protein as a risk factor for cardiovascular events in the general population. The goal of this study was to determine the relationship between target organ damage and high-sensitivity C-reactive protein in a cohort of Chinese patients......, carotid intima-media thickness, and renal impairment, were investigated. The median (25th and 75th percentiles) of high-sensitivity C-reactive protein in 619 patients with metabolic syndrome was 2.42 mg/L (0.75 and 3.66 mg/L) compared with 1.13 mg/L (0.51 and 2.46 mg/L) among 463 control subjects (P

  7. End-to-end process of hollow spacecraft structures with high frequency and low mass obtained with in-house structural optimization tool and additive manufacturing

    Directory of Open Access Journals (Sweden)

    Alexandru-Mihai CISMILIANU

    2017-09-01

    Full Text Available In the space sector the most decisive elements are: mass reduction, cost saving and minimum lead time; here, structural optimization and additive layer manufacturing (ALM fit best. The design must be driven by stiffness, because an important requirement for spacecraft (S/C structures is to reduce the dynamic coupling between the S/C and the launch vehicle. The objective is to create an end-to-end process, from the input given by the customer to the manufacturing of an aluminum part as light as possible but at the same time considerably stiffer while taking the full advantage of the design flexibility given by ALM. To design and optimize the parts, a specialized in-house tool was used, guaranteeing a load-sufficient material distribution. Using topological optimization, the iterations between the design and the stress departments were diminished, thus greatly reducing the lead time. In order to improve and lighten the obtained structure a design with internal cavities and hollow beams was considered. This implied developing of a procedure for powder evacuation through iterations with the manufacturer while optimizing the design for ALM. The resulted part can be then manufactured via ALM with no need of further design adjustments. To achieve a high-quality part with maximum efficiency, it is essential to have a loop between the design team and the manufacturer. Topological optimization and ALM work hand in hand if used properly. The team achieved a more efficient structure using topology optimization and ALM, than using conventional design and manufacturing methods.

  8. Characterization of Impact Damage in Ultra-High Performance Concrete Using Spatially Correlated Nanoindentation/SEM/EDX

    Science.gov (United States)

    Moser, R. D.; Allison, P. G.; Chandler, M. Q.

    2013-12-01

    Little work has been done to study the fundamental material behaviors and failure mechanisms of cement-based materials including ordinary Portland cement concrete and ultra-high performance concretes (UHPCs) under high strain impact and penetration loads at lower length scales. These high strain rate loadings have many possible effects on UHPCs at the microscale and nanoscale, including alterations in the hydration state and bonding present in phases such as calcium silicate hydrate, in addition to fracture and debonding. In this work, the possible chemical and physical changes in UHPCs subjected to high strain rate impact and penetration loads were investigated using a novel technique wherein nanoindentation measurements were spatially correlated with images using scanning electron microscopy and chemical composition using energy dispersive x-ray microanalysis. Results indicate that impact degrades both the elastic modulus and indentation hardness of UHPCs, and in particular hydrated phases, with damage likely occurring due to microfracturing and debonding.

  9. High-rate production of micro- and nanostructured surfaces: Injection molding and novel process for metal tooling manufacturing

    Science.gov (United States)

    De Jesus Vega, Marisely

    rapidly processed via liquid injection molding. LSR with its excellent mechanical properties, transparency, non-toxicity and rapid molding capabilities can bring the production of micro and nanostructured surfaces from laboratory research facilities to high-rate manufacturing. However, previous research on microstructured surfaces made off LSR does not focus on the processing aspect of this material. Therefore, there is a lack of understanding of how different processing conditions affect the replication of microstructures. Additionally, there are no reports molding nanostructures of LSR. Features between 115 microm and 0.250 microm were molded in this work and the effect of different processing conditions and features sizes were studied. For the last part of this work, a novel metal additive manufacturing technique was used for the production of microstructured surfaces to be used as tooling for injection molding. The printing method consists of metal pastes printed through a tip onto a steel substrate. Prior work has shown spreading and swelling of features when metal pastes extrude out of the printing tip. PDMS was studied as a binder material to minimize spreading and swelling of the features by curing right after printing. In addition, prior work has shown durability of this metal printed tool up to 5000 injection molding cycles. This work compares this durability to durability of commercially available selective laser sintering metal tools. Furthermore, surface roughness was studied as this is one of the most important things to consider when molding microchannels for certain applications.

  10. Knowledge-Based Detection and Assessment of Damaged Roads Using Post-Disaster High-Resolution Remote Sensing Image

    OpenAIRE

    Wang, Jianhua; Qin, Qiming; Zhao, Jianghua; Ye, Xin; Feng, Xiao; Qin, Xuebin; Yang, Xiucheng

    2015-01-01

    Road damage detection and assessment from high-resolution remote sensing image is critical for natural disaster investigation and disaster relief. In a disaster context, the pairing of pre-disaster and post-disaster road data for change detection and assessment is difficult to achieve due to the mismatch of different data sources, especially for rural areas where the pre-disaster data (i.e., remote sensing imagery or vector map) are hard to obtain. In this study, a knowledge-based method for ...

  11. SLAM: a fast high volume additive manufacturing concept by impact welding; application to Ti6Al4V alloy

    NARCIS (Netherlands)

    Wentzel, C.M.; Carton, E.P.; Kloosterman, A.

    2006-01-01

    Against the manufacturing requirement for both lower lead time and reduced machining time for titanium components, a new concept was conceived assembling sheet material and other stock into semi finished parts by (explosive) impact welding. It is believed that this concept (which we named SLAM)

  12. Instructional Materials in Manufacturing for Junior High School Industrial Arts. Final Report and Parts I-IV.

    Science.gov (United States)

    Ohio State Univ., Columbus.

    This Title XI Institute was designed and conducted to introduce the participants to inquiry and invention taking place in industrial arts curriculum across the United States. The institute participated in the inquiry stage through advanced study of manufacturing technology and industrial arts curriculum, and in the invention stage through the…

  13. Modelling of Mechanical Behavior at High Strain Rate of Ti-6al-4v Manufactured By Means of Direct Metal Laser Sintering Technique

    Science.gov (United States)

    Iannitti, Gianluca; Bonora, Nicola; Gentile, Domenico; Ruggiero, Andrew; Testa, Gabriel; Gubbioni, Simone

    2017-06-01

    In this work, the mechanical behavior of Ti-6Al-4V obtained by additive manufacturing technique was investigated, also considering the build direction. Dog-bone shaped specimens and Taylor cylinders were machined from rods manufactured by means of the EOSSINT M2 80 machine, based on Direct Metal Laser Sintering technique. Tensile tests were performed at strain rate ranging from 5E-4 s-1 to 1000 s-1 using an Instron electromechanical machine for quasistatic tests and a Direct-Tension Split Hopkinson Bar for dynamic tests. The mechanical strength of the material was described by a Johnson-Cook model modified to account for stress saturation occurring at high strain. Taylor cylinder tests and their corresponding numerical simulations were carried out in order to validate the constitutive model under a complex deformation path, high strain rates, and high temperatures.

  14. Modular mechatronic control of reconfigurable manufacturing system for mass customization manufacturing

    CSIR Research Space (South Africa)

    Xing, B

    2007-01-01

    Full Text Available Manufacturing companies are faced with the challenge of unpredictable, high frequency market changes in both local and international markets. There is a need for greater, more effective responsiveness by manufacturers to change their manufacturing...

  15. Effects of prior surface damage on high-temperature oxidation of Fe-, Ni-, and Co-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL; Lowe, Tracie M [ORNL; Pint, Bruce A [ORNL

    2009-01-01

    Multi-component metallic alloys have been developed to withstand high-temperature service in corrosive environments. Some of these applications, like exhaust valve seats in internal combustion engines, must also resist sliding, impact, and abrasion. The conjoint effects of temperature, oxidation, and mechanical contact can result in accelerated wear and the formation of complex surface layers whose properties differ from those of the base metal and the oxide scale that forms in the absence of mechanical contact. The authors have investigated the effects of prior surface damage, produced by scratch tests, on the localized reformation of oxide layers. Three high-performance commercial alloys, based on iron, nickel, and cobalt, were used as model materials. Thermogravimetric analysis (TGA) was used to determine their static oxidation rates at elevated temperature (850o C). A micro-abrasion, ball-cratering technique was used to measure oxide layer thickness and to compare it with TGA results. By using taper-sectioning techniques and energy-dispersive elemental mapping, a comparison was made between oxide compositions grown on non-damaged surfaces and oxides that formed on grooves produced by a diamond stylus. Microindentation and scratch hardness data revealed the effects of high temperature exposure on both the substrate hardness and the nature of oxide scale disruption. There were significant differences in elemental distribution between statically-formed oxides and those that formed on scratched regions

  16. Fiber Fabry-Perot Force Sensor with Small Volume and High Performance for Assessing Fretting Damage of Steam Generator Tubes.

    Science.gov (United States)

    Huang, Peijian; Wang, Ning; Li, Junying; Zhu, Yong; Zhang, Jie

    2017-12-13

    Measuring the radial collision force between the steam generator tube (SGT) and the tube support plate (TSP) is essential to assess the fretting damage of the SGT. In order to measure the radial collision force, a novel miniaturized force sensor based on fiber Fabry-Perot (F-P) was designed, and the principle and characteristics of the sensor were analyzed in detail. Then, the F-P force sensor was successfully fabricated and calibrated, and the overall dimensions of the encapsulated fiber F-P sensor were 17 mm × 5 mm × 3 mm (L × W × H). The sensor works well in humid, high pressure (10 MPa), high temperature (350 °C), and vibration (40 kHz) environments. Finally, the F-P force sensors were installed in a 1:1 steam generator test loop, and the radial collision force signals between the SGT and the TSP were obtained. The experiments indicated that the F-P sensor with small volume and high performance could help in assessing the fretting damage of the steam generator tubes.

  17. Kinetics of sublethal damage recovery in mouse lip mucosa comparing low and high-LET radiation

    International Nuclear Information System (INIS)

    Scalliet, P.; Landuyt, W.; Schueren, E. van der; Vynckier, S.; Wambersie, A.

    1989-01-01

    The effects of d(50)+Be neutrons on the lip mucosa in mice were investigated as a model of early effects. The biological endpoint eas the incidence of desquamation in the lower lip after selective irradiation of the snout of the animals. ED 50 (dose leading to desquamation in 50% of the animals) were calculated by probit analysis. Fractionated (two, four and ten fractions) and protracted (43.5, 11.5 and 0.88 Gy.h -1 ) irradiations have been carried out. Results were analysed using the mathematical method of Dale. An α/β of 39.6 Gy and a t 1/2 of recovery of sublethal damage of 47 min have been derived. These results have been compared to data previously obtained with cobalt-60 gamma rays. Using the same mathematical approach, and comparing similar fractionated and protracted experiments, an α/β of 7.4 Gy and a t 1/2 of recovery of 47 min have been calculated. There was no significant difference in the repair kinetics after irradiations with gamma rays or d(50)+Be neutrons. (orig.) [de

  18. Optical Fiber Demodulation System with High Performance for Assessing Fretting Damage of Steam Generator Tubes

    Directory of Open Access Journals (Sweden)

    Peijian Huang

    2018-01-01

    Full Text Available In order to access the fretting damage of the steam generator tube (SGT, a fast fiber Fabry-Perot (F-P non-scanning correlation demodulation system based on a super luminescent light emitting diode (SLED was performed. By demodulating the light signal coming out from the F-P force sensor, the radial collision force between the SGT and the tube support plate (TSP was interrogated. For higher demodulation accuracy, the effects of the center wavelength, bandwidth, and spectrum noise of SLED were discussed in detail. Specially, a piezoelectric ceramic transducer (PZT modulation method was developed to get rid of the interference of mode coupling induced by different types of fiber optics in the demodulation system. The reflectivity of optical wedge and F-P sensor was optimized. Finally, the demodulation system worked well in a 1:1 steam generator test loop and successfully demodulated a force signal of 32 N with a collision time of 2 ms.

  19. Semiconductor Manufacturing equipment introduction

    International Nuclear Information System (INIS)

    Im, Jong Sun

    2001-02-01

    This book deals with semiconductor manufacturing equipment. It is comprised of nine chapters, which are manufacturing process of semiconductor device, history of semiconductor manufacturing equipment, kinds and role of semiconductor manufacturing equipment, construction and method of semiconductor manufacturing equipment, introduction of various semiconductor manufacturing equipment, spots of semiconductor manufacturing, technical elements of semiconductor manufacturing equipment, road map of technology of semiconductor manufacturing equipment and semiconductor manufacturing equipment in the 21st century.

  20. Impact of doped boron concentration in emitter on high- and low-dose-rate damage in lateral PNP transistors

    International Nuclear Information System (INIS)

    Zheng Yuzhan; Lu Wu; Ren Diyuan; Wang Yiyuan; Wang Zhikuan; Yang Yonghui

    2010-01-01

    The characteristics of radiation damage under a high or low dose rate in lateral PNP transistors with a heavily or lightly doped emitter is investigated. Experimental results show that as the total dose increases, the base current of transistors would increase and the current gain decreases. Furthermore, more degradation has been found in lightly-doped PNP transistors, and an abnormal effect is observed in heavily doped transistors. The role of radiation defects, especially the double effects of oxide trapped charge, is discussed in heavily or lightly doped transistors. Finally, through comparison between the high- and low-dose-rate response of the collector current in heavily doped lateral PNP transistors, the abnormal effect can be attributed to the annealing of the oxide trapped charge. The response of the collector current, in heavily doped PNP transistors under high- and low-dose-rate irradiation is described in detail. (semiconductor integrated circuits)