WorldWideScience

Sample records for materials program mechanical

  1. Material Programming

    DEFF Research Database (Denmark)

    Vallgårda, Anna; Boer, Laurens; Tsaknaki, Vasiliki

    2017-01-01

    . Consequently we ask what the practice of programming and giving form to such materials would be like? How would we be able to familiarize ourselves with the dynamics of these materials and their different combinations of cause and effect? Which tools would we need and what would they look like? Will we program......, and color, but additionally being capable of sensing, actuating, and computing. Indeed, computers will not be things in and by themselves, but embedded into the materials that make up our surroundings. This also means that the way we interact with computers and the way we program them, will change...... these computational composites through external computers and then transfer the code them, or will the programming happen closer to the materials? In this feature we outline a new research program that floats between imagined futures and the development of a material programming practice....

  2. Mechanical properties test program on structural materials in a sodium environment

    International Nuclear Information System (INIS)

    Natesan, K.; Chopra, O.K.; Kassner, T.F.

    1979-10-01

    This document describes in detail the ongoing and planned US Test program on the mechanical properties of sodium-exposed Type 316 austenitic stainless and Fe-2 1/4 Cr-1 Mo ferritic steels. The test program is based on the Development Requirement Specifications (DRS) established by the DOE/Clinch River Breeder Reactor Project (CRBRP) Program Office, the general need for the development of LMFBR structural-design criteria established by the Nuclear Systems Materials Handbook, and the need for a fundamental understanding of materials behavior in a sodium environment, which is generic to LMFBR systems. The planned test program is an extension of work based on current knowledge of sodium chemistry and the influence of sodium purity on the mechanical properties of structural materials

  3. Program of assessment of mechanical and corrosion mechanical properties of reactor internals materials due to operation conditions in WWERs

    International Nuclear Information System (INIS)

    Ruscak, M.; Zamboch, M.

    1998-01-01

    Reactor internals are subject to three principle operation influences: neutron and gamma irradiation, mechanical stresses, both static and dynamic, and coolant chemistry. Several cases of damage have been reported in previous years in both boiling and pressure water reactors. They are linked with the term of irradiation assisted stress corrosion cracking as a possible damage mechanism. In WWERs, the principal material used for reactor internals is austenitic titanium stabilized stainless steel 08Kh18N10T, however high strength steels are used as well. To assess the changes of mechanical properties and to determine whether sensitivity to intergranular cracking can be increased by high neutron fluences, the experimental program has been started. The goal is to assure safe operation of the internals as well as life management for all planned operation period. The program consists of tests of material properties, both mechanical and corrosion-mechanical. Detailed neutron fluxes calculation as well as stress and deformation calculations are part of the assessment. Model of change will be proposed in order to plan inspections of the facility. In situ measurements of internals will be used to monitor exact status of structure during operation. Tensile specimens manufactured from both base metal and model weld joint have been irradiated to the total fluences of 3-20 dpa. Changes of mechanical properties are tested by the tensile test, stress corrosion cracking tests are performed in the autoclave with water loop and active loading. Operation temperature, pressure and water chemistry are chosen for the tests. (author)

  4. Overview of U.S. LMFBR structural materials mechanical properties program

    International Nuclear Information System (INIS)

    Horak, J.A.; Purdy, C.M.

    This paper presents the objective, scope, and status of the U.S. Department of Energy's Materials and Structures Program to develop a data base on mechanical properties of structural materials for out-of-core structures and components for LMFBRs. Information on the development of a reference data base on materials for the reactor system, reactor enclosure system, primary heat transport system, intermediate heat transport system, and steam generator system is included. In addition, the development of the data and analyses to account for the effects of temperature and stress, as well as water/steam, sodium, and radiation environments, is described. Plans for the development of alternative materials for future out-of-core applications are presented. (author)

  5. Mechanical Material Engineering

    International Nuclear Information System (INIS)

    Kim, Mun Il

    1993-01-01

    This book introduced mechanical material with introduction, basic problems about metal ingredient of machine of metal and alloy, property of metal material mechanical metal material such as categorization of metal material and high tensile structure steel, mechanic design and steel material with three important points on using of steel materials, selection and directions machine structural steel, selection and directions of steel for tool, selection and instruction of special steel like stainless steel and spring steel, nonferrous metal materials and plastic.

  6. Mechanical design engineering. NASA/university advanced design program: Lunar Bulk Material Transport Vehicle

    Science.gov (United States)

    Daugherty, Paul; Griner, Stewart; Hendrix, Alan; Makarov, Chris; Martiny, Stephen; Meyhoefer, Douglas Ralph; Platt, Cody Claxton; Sivak, John; Wheeler, Elizabeth Fitch

    1988-01-01

    The design of a Lunar Bulk Material Transport Vehicle (LBMTV) is discussed. Goals set in the project include a payload of 50 cubic feet of lunar soil with a lunar of approximately 800 moon-pounds, a speed of 15 mph, and the ability to handle a grade of 20 percent. Thermal control, an articulated steering mechanism, a dump mechanism, a self-righting mechanism, viable power sources, and a probable control panel are analyzed. The thermal control system involves the use of small strip heaters to heat the housing of electronic equipment in the absence of sufficient solar radiation and multi-layer insulation during periods of intense solar radiation. The entire system uses only 10 W and weighs about 60 pounds, or 10 moon-pounds. The steering mechanism is an articulated steering joint at the center of the vehicle. It utilizes two actuators and yields a turning radius of 10.3 feet. The dump mechanism rotates the bulk material container through an angle of 100 degree using one actuator. The self-righting mechanism consists of two four bar linkages, each of which is powered by the same size actuator as the other linkages. The LBMTV is powered by rechargeable batteries. A running time of at least two hours is attained under a worst case analysis. The weight of the batteries is 100 pounds. A control panel consisting of feedback and control instruments is described. The panel includes all critical information necessary to control the vehicle remotely. The LBMTV is capable of handling many types of cargo. It is able to interface with many types of removable bulk material containers. These containers are made to interface with the three-legged walker, SKITTER. The overall vehicle is about 15 feet in length and has a weight of about 1000 pounds, or 170 lunar pounds.

  7. Methodology for developing teaching activities and materials for use in fluid mechanics courses in undergraduate engineering programs

    Directory of Open Access Journals (Sweden)

    Pedro Javier Gamez-Montero

    2015-03-01

    Full Text Available “Mechanics” and “Fluids” are familiar concepts for any newly-registered engineering student. However, when combined into the term “Fluid Mechanics”, students are thrust into the great unknown. The present article demonstrates the process of adaptation employed by the Fluid Mechanics course in the undergraduate engineering program, along with the teaching methodology, teaching materials and results obtained, evaluating the final objective in terms of student satsfaction and level of learning.

  8. Material studies in the frame of CLIC Accelerating structures production conducted within the Mechanics program together with Metso Oy

    CERN Document Server

    Nurminen, Janne

    2012-01-01

    MeChanICs (Marie Curie Linking Industry to CERN) is an Industry to Academia Partnership and Pathways (IAPP) platform for precision manufacturing knowledge exchange bringing together five Finnish manufacturing companies with Helsinki Insitute of Physics (HIP) and CERN. The scientific objective of MeChanICs project is to contribute to the manufacturing RTD of CLIC enabling technologies. The focus is on the design, materials, machining, brazing and assembly of A CLIC accelerating structure. This study deals with the materials work package of the program and wants to explore the following items: 1) producing copper accelerating structures for CLIC from raw copper powder by near net shape hot isostatic pressing (HIP). 2) The feasibility to use HIP diffusion bonding of the accelerator structures as a function of surface quality and applied temperature and pressure. 3) Brazing for CLIC AS auxiliary systems, like water cooling or damping manifolds, to the disc stack by coating one of the brazing partners with an enab...

  9. Mechanical meta-materials

    NARCIS (Netherlands)

    Zadpoor, A.A.

    2016-01-01

    The emerging concept of mechanical meta-materials has received increasing attention during the last few years partially due to the advances in additive manufacturing techniques that have enabled fabricating materials with arbitrarily complex micro/nano-architectures. The rationally designed

  10. Mechanics of soft materials

    CERN Document Server

    Volokh, Konstantin

    2016-01-01

    This book provides a concise introduction to soft matter modelling. It offers an up-to-date review of continuum mechanical description of soft and biological materials from the basics to the latest scientific materials. It includes multi-physics descriptions, such as chemo-, thermo-, electro- mechanical coupling. It derives from a graduate course at Technion that has been established in recent years. It presents original explanations for some standard materials and features elaborated examples on all topics throughout the text. PowerPoint lecture notes can be provided to instructors. .

  11. Advanced Industrial Materials Program

    Science.gov (United States)

    Stooksbury, F.

    1994-06-01

    The mission of the Advanced Industrial Materials (AIM) program is to commercialize new/improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. Program investigators in the DOE national laboratories are working with about 100 companies, including 15 partners in CRDA's. Work is being done on intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The program supports other efforts in the Office of Industrial Technologies to assist the energy-consuming process industries. The aim of the AIM program is to bring materials from basic research to industrial application to strengthen the competitive position of US industry and save energy.

  12. Materials Sciences Programs

    International Nuclear Information System (INIS)

    1977-01-01

    A compilation and index of the ERDA materials sciences program is presented. This compilation is intended for use by administrators, managers, and scientists to help coordinate research and as an aid in selecting new programs

  13. Fracture mechanical materials characterisation

    International Nuclear Information System (INIS)

    Wallin, K.; Planman, T.; Nevalainen, M.

    1998-01-01

    The experimental fracture mechanics development has been focused on the determination of reliable lower-bound fracture toughness estimates from small and miniature specimens, in particular considering the statistical aspects and loading rate effects of fracture mechanical material properties. Additionally, materials aspects in fracture assessment of surface cracks, with emphasis on the transferability of fracture toughness data to structures with surface flaws have been investigated. Further a modified crack-arrest fracture toughness test method, to increase the effectiveness of testing, has been developed. (orig.)

  14. Mechanics of moving materials

    CERN Document Server

    Banichuk, Nikolay; Neittaanmäki, Pekka; Saksa, Tytti; Tuovinen, Tero

    2014-01-01

    This book deals with theoretical aspects of modelling the mechanical behaviour of manufacturing, processing, transportation or other systems in which the processed or supporting material is travelling through the system. Examples of such applications include paper making, transmission cables, band saws, printing presses, manufacturing of plastic films and sheets, and extrusion of aluminium foil, textiles and other materials.   The work focuses on out-of-plane dynamics and stability analysis for isotropic and orthotropic travelling elastic and viscoelastic materials, with and without fluid-structure interaction, using analytical and semi-analytical approaches.  Also topics such as fracturing and fatigue are discussed in the context of moving materials. The last part of the book deals with optimization problems involving physical constraints arising from the stability and fatigue analyses, including uncertainties in the parameters.   The book is intended for researchers and specialists in the field, providin...

  15. Materials Science Programs

    International Nuclear Information System (INIS)

    1990-03-01

    The Division of Materials Sciences is located within the Department of Energy in the Office of Basic Energy Sciences. The Office of Basic Energy Sciences reports to the Director of the Office of Energy Research. The Director of this office is appointed by the President with Senate consent. The Director advises the Secretary on the physical research program; monitors the Department's R ampersand D programs; advises the Secretary on management of the laboratories under the jurisdiction of the Department, excluding those that constitute part of the nuclear weapon complex; and advises the Secretary on basic and applied research activities of the Department. The research covers a spectrum of scientific and engineering areas of interest to the Department of Energy and is conducted generally by personnel trained in the disciplines of Solid State Physics, Metallurgy, Ceramics, Chemistry, Polymers and Materials Science. The Materials Sciences Division supports basic research on materials properties and phenomena important to all energy systems. The aim is to provide the necessary base of materials knowledge required to advance the nation's energy programs. This report contains a listing of research underway in FY 1989 together with a convenient index to the Division's programs

  16. Mechanical performance of MFE materials

    International Nuclear Information System (INIS)

    Opperman, E.K.; Straalsund, J.L.

    1977-01-01

    The objective of this program is to establish the effects of Magnetic Fusion Reactor (MFR) environments on the mechanical properties of candidate MFR materials. As a first step in meeting this end, a torsional system was developed to measure creep resulting from incident light ions of energies ranging from 5 to 60 MeV and displacement rates up to 1 x 10 -5 dpa/sec. Light particle simulation of creep and cyclic behavior will be necessary during early stages of MFR materials devlopment because high flux neutron sources will not be available during this period. The specific objectives of this six month period were to finalize the thermal creep testing phase and initiate creep measurements under proton irradiation. The goals of the first irradiation were to determine if proton induced creep could, in fact, be resolved from thermal creep and to give the entire system, including all beam defining, collimating and measurement components, a thorough test in a radiation environment

  17. Mechanical seal program

    International Nuclear Information System (INIS)

    Lowery, G.B.

    1983-01-01

    The experimental plans and timing for completion of the mechanical seal program for both the slurry and transfer pumps are given. The slurry pump seal program will be completed by April 1984 with turnover of two seals in pumps to SRP Tank 15H. Transfer pump seal design will be released for plant use by May 1984. Also included are various other pump and seal related tests

  18. High temperature materials and mechanisms

    CERN Document Server

    2014-01-01

    The use of high-temperature materials in current and future applications, including silicone materials for handling hot foods and metal alloys for developing high-speed aircraft and spacecraft systems, has generated a growing interest in high-temperature technologies. High Temperature Materials and Mechanisms explores a broad range of issues related to high-temperature materials and mechanisms that operate in harsh conditions. While some applications involve the use of materials at high temperatures, others require materials processed at high temperatures for use at room temperature. High-temperature materials must also be resistant to related causes of damage, such as oxidation and corrosion, which are accelerated with increased temperatures. This book examines high-temperature materials and mechanisms from many angles. It covers the topics of processes, materials characterization methods, and the nondestructive evaluation and health monitoring of high-temperature materials and structures. It describes the ...

  19. BUILDING MATERIALS RECLAMATION PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    David C. Weggel; Shen-En Chen; Helene Hilger; Fabien Besnard; Tara Cavalline; Brett Tempest; Adam Alvey; Madeleine Grimmer; Rebecca Turner

    2010-08-31

    This report describes work conducted on the Building Materials Reclamation Program for the period of September 2008 to August 2010. The goals of the project included selecting materials from the local construction and demolition (C&D) waste stream and developing economically viable reprocessing, reuse or recycling schemes to divert them from landfill storage. Educational resources as well as conceptual designs and engineering feasibility demonstrations were provided for various aspects of the work. The project was divided into two distinct phases: Research and Engineering Feasibility and Dissemination. In the Research Phase, a literature review was initiated and data collection commenced, an advisory panel was organized, and research was conducted to evaluate high volume C&D materials for nontraditional use; five materials were selected for more detailed investigations. In the Engineering Feasibility and Dissemination Phase, a conceptual study for a regional (Mecklenburg and surrounding counties) collection and sorting facility was performed, an engineering feasibility project to demonstrate the viability of recycling or reuse schemes was created, the literature review was extended and completed, and pedagogical materials were developed. Over the two-year duration of the project, all of the tasks and subtasks outlined in the original project proposal have been completed. The Final Progress Report, which briefly describes actual project accomplishments versus the tasks/subtasks of the original project proposal, is included in Appendix A of this report. This report describes the scientific/technical aspects (hypotheses, research/testing, and findings) of six subprojects that investigated five common C&D materials. Table 1 summarizes the six subprojects, including the C&D material studied and the graduate student and the faculty advisor on each subproject.

  20. Building Materials Reclamation Program

    International Nuclear Information System (INIS)

    Weggel, David C.; Chen, Shen-En; Hilger, Helene; Besnard, Fabien; Cavalline, Tara; Tempest, Brett; Alvey, Adam; Grimmer, Madeleine; Turner, Rebecca

    2011-01-01

    This report describes work conducted on the Building Materials Reclamation Program for the period of September 2008 to August 2010. The goals of the project included selecting materials from the local construction and demolition (C and D) waste stream and developing economically viable reprocessing, reuse or recycling schemes to divert them from landfill storage. Educational resources as well as conceptual designs and engineering feasibility demonstrations were provided for various aspects of the work. The project was divided into two distinct phases: Research and Engineering Feasibility and Dissemination. In the Research Phase, a literature review was initiated and data collection commenced, an advisory panel was organized, and research was conducted to evaluate high volume C and D materials for nontraditional use; five materials were selected for more detailed investigations. In the Engineering Feasibility and Dissemination Phase, a conceptual study for a regional (Mecklenburg and surrounding counties) collection and sorting facility was performed, an engineering feasibility project to demonstrate the viability of recycling or reuse schemes was created, the literature review was extended and completed, and pedagogical materials were developed. Over the two-year duration of the project, all of the tasks and subtasks outlined in the original project proposal have been completed. The Final Progress Report, which briefly describes actual project accomplishments versus the tasks/subtasks of the original project proposal, is included in Appendix A of this report. This report describes the scientific/technical aspects (hypotheses, research/testing, and findings) of six subprojects that investigated five common C and D materials. Table 1 summarizes the six subprojects, including the C and D material studied and the graduate student and the faculty advisor on each subproject.

  1. Continuum mechanics of anisotropic materials

    CERN Document Server

    Cowin, Stephen C

    2013-01-01

    Continuum Mechanics of Anisotropic Materials(CMAM) presents an entirely new and unique development of material anisotropy in the context of an appropriate selection and organization of continuum mechanics topics. These features will distinguish this continuum mechanics book from other books on this subject. Textbooks on continuum mechanics are widely employed in engineering education, however, none of them deal specifically with anisotropy in materials. For the audience of Biomedical, Chemical and Civil Engineering students, these materials will be dealt with more frequently and greater accuracy in their analysis will be desired. Continuum Mechanics of Anisotropic Materials' author has been a leader in the field of developing new approaches for the understanding of anisotropic materials.

  2. Mechanical engineers' handbook, materials and engineering mechanics

    CERN Document Server

    Kutz, Myer

    2015-01-01

    Full coverage of materials and mechanical design inengineering Mechanical Engineers' Handbook, Fourth Edition provides aquick guide to specialized areas you may encounter in your work,giving you access to the basics of each and pointing you towardtrusted resources for further reading, if needed. The accessibleinformation inside offers discussions, examples, and analyses ofthe topics covered. This first volume covers materials and mechanical design, givingyou accessible and in-depth access to the most common topics you'llencounter in the discipline: carbon and alloy steels, stainlesssteels, a

  3. Mechanics of advanced functional materials

    CERN Document Server

    Wang, Biao

    2013-01-01

    Mechanics of Advanced Functional Materials emphasizes the coupling effect between the electric and mechanical field in the piezoelectric, ferroelectric and other functional materials. It also discusses the size effect on the ferroelectric domain instability and phase transition behaviors using the continuum micro-structural evolution models. Functional materials usually have a very wide application in engineering due to their unique thermal, electric, magnetic, optoelectronic, etc., functions. Almost all the applications demand that the material should have reasonable stiffness, strength, fracture toughness and the other mechanical properties. Furthermore, usually the stress and strain fields on the functional materials and devices have some important coupling effect on the functionality of the materials. Much progress has been made concerning the coupling electric and mechanical behaviors such as the coupled electric and stress field distribution in piezoelectric solids, ferroelectric domain patterns in ferr...

  4. Leaching Mechanisms Program. Annual report

    International Nuclear Information System (INIS)

    Dougherty, D.; Colombo, P.; Doty, R.; Fuhrmann, M.

    1984-09-01

    The primary goal of this work is to determine the leaching mechanisms of a variety of matrix materials either in use or being considered for the solidification of low-level radioactive wastes by defense and commercial waste generators. Since this program is new and did not formally begin until May of FY 84, the results reported here are few and preliminary. Efforts were concentrated in the following activities: (1) The literature search for leaching data and proposed leaching models and mechanisms for low-level waste. (2) Data base development for leaching data being compiled from the literature and from the leaching experiments in this program. (3) The selection of solidification agents for the experimental part of the program. (4) Fabrication of leach samples and initiation of leach testing. 28 references, 9 figures, 4 tables

  5. Mechanics for materials and technologies

    CERN Document Server

    Goldstein, Robert; Murashkin, Evgenii

    2017-01-01

    This book shows impressively how complex mathematical modeling of materials can be applied to technological problems. Top-class researchers present the theoretical approaches in modern mechanics and apply them to real-world problems in solid mechanics, creep, plasticity, fracture, impact, and friction. They show how they can be applied to technological challenges in various fields like aerospace technology, biological sciences and modern engineering materials.

  6. Fusion program research materials inventory

    International Nuclear Information System (INIS)

    Roche, T.K.; Wiffen, F.W.; Davis, J.W.; Lechtenberg, T.A.

    1984-01-01

    Oak Ridge National Laboratory maintains a central inventory of research materials to provide a common supply of materials for the Fusion Reactor Materials Program. This will minimize unintended material variations and provide for economy in procurement and for centralized record keeping. Initially this inventory is to focus on materials related to first-wall and structural applications and related research, but various special purpose materials may be added in the future. The use of materials from this inventory for research that is coordinated with or otherwise related technically to the Fusion Reactor Materials Program of DOE is encouraged

  7. Mechanical Treatment: Material Recovery Facilities

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Bilitewski, B.

    2011-01-01

    A wide variety of mechanical treatment unit processes, including manual sorting, is described in Chapter 7.1. These unit processes may be used as a single separate operation (e.g. baling of recyclable cardboard) or as a single operation before or after biological and thermal treatment processes (e.......g. shredding prior to incineration or screening after composting). The mechanical treatment unit process is in the latter case an integrated part of the overall treatment usually with the purpose of improving the quality of the input material, or the efficiency or stability of the biological or thermal process......, or improving the quality of the output material. Examples hereof appear in the chapters on biological and thermal treatment. Mechanical treatment unit processes may also appear at industries using recycled material as part of their feedstock, for example, for removing impurities and homogenizing the material...

  8. Methodology for Developing Teaching Activities and Materials for Use in Fluid Mechanics Courses in Undergraduate Engineering Programs

    Science.gov (United States)

    Gamez-Montero, P. Javier; Raush, Gustavo; Domènech, Lluis; Castilla, Robert; García-Vílchez, Mercedes; Moreno, Hipòlit; Carbó, Albert

    2015-01-01

    "Mechanics" and "Fluids" are familiar concepts for any newly-registered engineering student. However, when combined into the term "Fluid Mechanics", students are thrust into the great unknown. The present article demonstrates the process of adaptation employed by the Fluid Mechanics course in the undergraduate…

  9. Particle Suspension Mechanisms - Supplemental Material

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, M B

    2011-03-03

    This supplemental material provides a brief introduction to particle suspension mechanisms that cause exfoliated skin cells to become and remain airborne. The material presented here provides additional context to the primary manuscript and serves as background for designing possible future studies to assess the impact of skin cells as a source of infectious aerosols. This introduction is not intended to be comprehensive and interested readers are encouraged to consult the references cited.

  10. Foreign material exclusion program

    International Nuclear Information System (INIS)

    Perez Moreno, J.; Folguera Mateo, M.

    2015-01-01

    Foreign material is any element that is not part of the system as it has been designed. For example dirt, loose parts, wires, chips, etc. that may affect the operation of the system or component. (Author)

  11. Mechanics of fiber reinforced materials

    Science.gov (United States)

    Sun, Huiyu

    This dissertation is dedicated to mechanics of fiber reinforced materials and the woven reinforcement and composed of four parts of research: analytical characterization of the interfaces in laminated composites; micromechanics of braided composites; shear deformation, and Poisson's ratios of woven fabric reinforcements. A new approach to evaluate the mechanical characteristics of interfaces between composite laminae based on a modified laminate theory is proposed. By including an interface as a special lamina termed the "bonding-layer" in the analysis, the mechanical properties of the interfaces are obtained. A numerical illustration is given. For micro-mechanical properties of three-dimensionally braided composite materials, a new method via homogenization theory and incompatible multivariable FEM is developed. Results from the hybrid stress element approach compare more favorably with the experimental data than other existing numerical methods widely used. To evaluate the shearing properties for woven fabrics, a new mechanical model is proposed during the initial slip region. Analytical results show that this model provides better agreement with the experiments for both the initial shear modulus and the slipping angle than the existing models. Finally, another mechanical model for a woven fabric made of extensible yarns is employed to calculate the fabric Poisson's ratios. Theoretical results are compared with the available experimental data. A thorough examination on the influences of various mechanical properties of yarns and structural parameters of fabrics on the Poisson's ratios of a woven fabric is given at the end.

  12. Mechanical Properties of Composite Materials

    Directory of Open Access Journals (Sweden)

    Mitsuhiro Okayasu

    2014-10-01

    Full Text Available An examination has been made of the mechanical and failure properties of several composite materials, such as a short and a long carbon fiber reinforced plastic (short- and long-CFRP and metal based composite material. The short CFRP materials were used for a recycled CFRP which fabricated by the following process: the CFRP, consisting of epoxy resin with carbon fiber, is injected to a rectangular plate cavity after mixing with acrylonitrile butadiene styrene resin with different weight fractions of CFRP. The fatigue and ultimate tensile strength (UTS increased with increasing CFRP content. These correlations, however, break down, especially for tensile strength, as the CFPR content becomes more than 70%. Influence of sample temperature on the bending strength of the long-CFRP was investigated, and it appears that the strength slightly degreases with increasing the temperature, due to the weakness in the matrix. Broken fiber and pull-out or debonding between the fiber and matrix were related to the main failure of the short- and long-CFRP samples. Mechanical properties of metal based composite materials have been also investigated, where fiber-like high hardness CuAl2 structure is formed in aluminum matrix. Excellent mechanical properties were obtained in this alloy, e.g., the higher strength and the higher ductility, compared tothe same alloy without the fiber-like structure. There are strong anisotropic effects on the mechanical properties due to the fiber-like metal composite in a soft Al based matrix.

  13. Mechanical Response of Thermoelectric Materials

    Energy Technology Data Exchange (ETDEWEB)

    Wereszczak, Andrew A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Case, Eldon D. [Michigan State Univ., East Lansing, MI (United States)

    2015-05-01

    A sufficient mechanical response of thermoelectric materials (TEMats) to structural loadings is a prerequisite to the exploitation of any candidate TEMat's thermoelectric efficiency. If a TEMat is mechanically damaged or cracks from service-induced stresses, then its thermal and electrical functions can be compromised or even cease. Semiconductor TEMats tend to be quite brittle and have a high coefficient of thermal expansion; therefore, they can be quite susceptible to mechanical failure when subjected to operational thermal gradients. Because of this, sufficient mechanical response (vis-a-vis, mechanical properties) of any candidate TEMat must be achieved and sustained in the context of the service-induced stress state to which it is subjected. This report provides an overview of the mechanical responses of state-of-the-art TEMats; discusses the relevant properties that are associated with those responses and their measurement; and describes important, nonequilibrium phenomena that further complicate their use in thermoelectric devices. For reference purposes, the report also includes several appendixes that list published data on elastic properties and strengths of a variety of TEMats.

  14. BWR mechanics and materials technology update

    International Nuclear Information System (INIS)

    Kiss, E.

    1983-01-01

    This paper discusses technical results obtained from a variety of important programs underway at General Electric's Nuclear Engineering Division. The principal objective of these programs is to qualify and improve BWR product related technologies that fall broadly under the disciplines of Applied Mechanics and Materials Engineering. The paper identifies and deals with current technical issues that are of general importance to the LWR industry albeit the specific focus is directed to the development and qualification of analytical predictive methods and criteria, and improved materials for use in the design of the BWR. In this paper, specific results and accomplishments are summarized to provide a braod perspective of technology advances. Results are presented in sections which discuss: dynamic analysis and modeling; fatigue and fracture evaluation; materials engineering advances; and flow induced vibration. (orig.)

  15. Japanese materials program and FFTF

    International Nuclear Information System (INIS)

    Ishino, Shiori

    1988-01-01

    Japanese materials program has been briefly reviewed and the associated university program, which is still in a provisional stage has been described in some detail. Important elements of the university proposal will be 1) construction of a high energy high fluence neutron irradiation facility, 2) establishing or expanding local research centers including hot laboratories, and 3) promotion of fundamental studies. The FFTF/MOTA Project is a very important constituent of the whole program, the results coming out of which should be well coordinated with other fundamental research programs to extract full essence needed for the advancement of realization of fusion energy. (author)

  16. Computational Mechanics for Heterogeneous Materials

    Energy Technology Data Exchange (ETDEWEB)

    Lechman, Jeremy B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Baczewski, Andrew David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bond, Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Erikson, William W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lehoucq, Richard B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mondy, Lisa Ann [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Noble, David R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pierce, Flint [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Christine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); van Swol, Frank B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yarrington, Cole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2013-11-01

    The subject of this work is the development of models for the numerical simulation of matter, momentum, and energy balance in heterogeneous materials. These are materials that consist of multiple phases or species or that are structured on some (perhaps many) scale(s). By computational mechanics we mean to refer generally to the standard type of modeling that is done at the level of macroscopic balance laws (mass, momentum, energy). We will refer to the flow or flux of these quantities in a generalized sense as transport. At issue here are the forms of the governing equations in these complex materials which are potentially strongly inhomogeneous below some correlation length scale and are yet homogeneous on larger length scales. The question then becomes one of how to model this behavior and what are the proper multi-scale equations to capture the transport mechanisms across scales. To address this we look to the area of generalized stochastic process that underlie the transport processes in homogeneous materials. The archetypal example being the relationship between a random walk or Brownian motion stochastic processes and the associated Fokker-Planck or diffusion equation. Here we are interested in how this classical setting changes when inhomogeneities or correlations in structure are introduced into the problem. Aspects of non-classical behavior need to be addressed, such as non-Fickian behavior of the mean-squared-displacement (MSD) and non-Gaussian behavior of the underlying probability distribution of jumps. We present an experimental technique and apparatus built to investigate some of these issues. We also discuss diffusive processes in inhomogeneous systems, and the role of the chemical potential in diffusion of hard spheres is considered. Also, the relevance to liquid metal solutions is considered. Finally we present an example of how inhomogeneities in material microstructure introduce fluctuations at the meso-scale for a thermal conduction problem

  17. Fossil Energy Materials Program conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R. (comp.)

    1987-08-01

    The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Program to fulfill that responsibility. In addition to the AR and TD Materials Program, which is designed to address in a generic way the materials needs of fossil energy systems, specific materials support activities are also sponsored by the various line organizations such as the Office of Coal Gasification. A conference was held at Oak Ridge, Tennessee on May 19-21, 1987, to present and discuss the results of program activities during the past year. The conference program was organized in accordance with the research thrust areas we have established. These research thrust areas include structural ceramics (particularly fiber-reinforced ceramic composites), corrosion and erosion, and alloy development and mechanical properties. Eighty-six people attended the conference. Papers have been entered individually into EDB and ERA. (LTN)

  18. The UKAEA mechanical test programs in air

    International Nuclear Information System (INIS)

    Wood, D.S.

    1977-01-01

    The design of CDFR will be based on the mechanical behaviour of materials in air, although at a later date account may need to be taken of sodium effects. The need for this Information is outlined in the introductory paper. The extent of the air programs and preliminary findings are described in this paper

  19. Orientation: Automotive Mechanics Instructional Program. Block 1.

    Science.gov (United States)

    O'Brien, Ralph D.

    The first six instructional blocks in automotive mechanics, the lessons and supportive information in the document provide a guide for teachers in planning an instructional program in the basic theory and practice of a beginning course at the secondary and post-secondary level. The material, as organized, is a suggested sequence of instruction…

  20. The UKAEA mechanical test programs in air

    Energy Technology Data Exchange (ETDEWEB)

    Wood, D S [UKAEA, RNPDL, Risley (United Kingdom)

    1977-07-01

    The design of CDFR will be based on the mechanical behaviour of materials in air, although at a later date account may need to be taken of sodium effects. The need for this Information is outlined in the introductory paper. The extent of the air programs and preliminary findings are described in this paper.

  1. Materials selection in mechanical design

    International Nuclear Information System (INIS)

    Ashby, M.F.; Cebon, D.

    1993-01-01

    A novel materials-selection procedure has been developed and implemented in software. The procedure makes use of Materials Selection Charts: a new way of displaying material property data; and performance indices: combinations of material properties which govern performance. Optimisation methods are employed for simultaneous selection of both material and shape. (orig.)

  2. Materials selection in mechanical design

    OpenAIRE

    Ashby , M.; Cebon , D.

    1993-01-01

    A novel materials-selection procedure has been developed and implemented in software. The procedure makes use of Materials Selection Charts: a new way of displaying material property data; and performance indices: combinations of material properties which govern performance. Optimisation methods are employed for simultaneous selection of both material and shape.

  3. Mechanics of materials an introduction to engineering technology

    CERN Document Server

    Ghavami, Parviz

    2015-01-01

    This book, framed in the processes of engineering analysis and design, presents concepts in mechanics of materials for students in two-year or four-year programs in engineering technology, architecture, and building construction, as well as for students in vocational schools and technical institutes. Using the principles and laws of mechanics, physics, and the fundamentals of engineering, Mechanics of Materials: An Introduction for Engineering Technology will help aspiring and practicing engineers and engineering technicians from across disciplines—mechanical, civil, chemical, and electrical—apply concepts of engineering mechanics for analysis and design of materials, structures, and machine components. The book is ideal for those seeking a rigorous, algebra/trigonometry-based text on the mechanics of materials. This book also: ·       Elucidates concepts of engineering mechanics in materials, including stress and strain, force systems on structures, moment of inertia, and shear and bending moments...

  4. Deformation and fracture mechanics of engineering materials

    National Research Council Canada - National Science Library

    Hertzberg, Richard W; Vinci, Richard Paul; Hertzberg, Jason L

    2012-01-01

    "Hertzberg's 5th edition of Deformation & Fracture Mechanics of Engineering Materials offers several new features including a greater number and variety of homework problems using more computational software...

  5. Mechanical properties of irradiated materials

    International Nuclear Information System (INIS)

    Robertson, I.M.; Robach, J.; Wirth, B.

    2001-01-01

    The effect of irradiation on the mechanical properties of metals is considered with particular attention being paid to the development of defect-free channels following uniaxial tensile loading. The in situ transmission electron microscope deformation technique is coupled with dislocation dynamic computer simulations to reveal the fundamental processes governing the elimination of defects by glissile dislocations. The observations of preliminary experiments are reported.(author)

  6. Statistical mechanics of program systems

    International Nuclear Information System (INIS)

    Neirotti, Juan P; Caticha, Nestor

    2006-01-01

    We discuss the collective behaviour of a set of operators and variables that constitute a program and the emergence of meaningful computational properties in the language of statistical mechanics. This is done by appropriately modifying available Monte Carlo methods to deal with hierarchical structures. The study suggests, in analogy with simulated annealing, a method to automatically design programs. Reasonable solutions can be found, at low temperatures, when the method is applied to simple toy problems such as finding an algorithm that determines the roots of a function or one that makes a nonlinear regression. Peaks in the specific heat are interpreted as signalling phase transitions which separate regions where different algorithmic strategies are used to solve the problem

  7. Material control system simulator program reference manual

    Energy Technology Data Exchange (ETDEWEB)

    Hollstien, R.B.

    1978-01-24

    A description is presented of a Material Control System Simulator (MCSS) program for determination of material accounting uncertainty and system response to particular adversary action sequences that constitute plausible material diversion attempts. The program is intended for use in situations where randomness, uncertainty, or interaction of adversary actions and material control system components make it difficult to assess safeguards effectiveness against particular material diversion attempts. Although MCSS may be used independently in the design or analysis of material handling and processing systems, it has been tailored toward the determination of material accountability and the response of material control systems to adversary action sequences.

  8. Material control system simulator program reference manual

    International Nuclear Information System (INIS)

    Hollstien, R.B.

    1978-01-01

    A description is presented of a Material Control System Simulator (MCSS) program for determination of material accounting uncertainty and system response to particular adversary action sequences that constitute plausible material diversion attempts. The program is intended for use in situations where randomness, uncertainty, or interaction of adversary actions and material control system components make it difficult to assess safeguards effectiveness against particular material diversion attempts. Although MCSS may be used independently in the design or analysis of material handling and processing systems, it has been tailored toward the determination of material accountability and the response of material control systems to adversary action sequences

  9. Materials program for magnetic fusion energy

    International Nuclear Information System (INIS)

    Zwilsky, K.M.; Cohen, M.M.; Finfgeld, C.R.; Reuther, T.C.

    1978-01-01

    The Magnetic Fusion Reactor Materials Program is currently operating at a level of $7.8M. The program is divided into four technical areas which cover both short and long term problems. These are: Alloy Development for Irradiation Performance, Damage Analysis and Fundamental Studies, Plasma-Materials Interaction, and Special Purpose Materials. A description of the program planning process, the continuing management structure, and the resulting documents is presented

  10. Materials Characterization Center program plan

    International Nuclear Information System (INIS)

    Nelson, R.D.; Ross, W.A.; Hill, O.F.; Mendel, J.E.; Merz, M.D.; Turcotte, R.P.

    1980-03-01

    The Materials Characterization Center (MCC) has been established at Pacific Northwest Laboratory as part of the Materials Characterization Organization for providing an authoritative, referenceable basis for establishing nuclear waste material properties and test methods. The MCC will provide a data base that will include information on the components of the waste emplacement package - the spent fuel or processed waste form and the engineered barriers - and their interaction with each other and as affected by the environment. The MCC will plan materials testing, develop and document procedures, collect and analyze existing materials data, and conduct tests as necessary

  11. Overview of NASA's Microgravity Materials Science Program

    Science.gov (United States)

    Downey, James Patton

    2012-01-01

    The microgravity materials program was nearly eliminated in the middle of the aughts due to budget constraints. Hardware developments were eliminated. Some investigators with experiments that could be performed using ISS partner hardware received continued funding. Partnerships were established between US investigators and ESA science teams for several investigations. ESA conducted peer reviews on the proposals of various science teams as part of an ESA AO process. Assuming he or she was part of a science team that was selected by the ESA process, a US investigator would submit a proposal to NASA for grant funding to support their part of the science team effort. In a similar manner, a US materials investigator (Dr. Rohit Trivedi) is working as a part of a CNES selected science team. As funding began to increase another seven materials investigators were selected in 2010 through an NRA mechanism to perform research related to development of Materials Science Research Rack investigations. One of these has since been converted to a Glovebox investigation.

  12. Materials and mechanisms of hole superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, J.E., E-mail: jhirsch@ucsd.edu [Department of Physics, University of California, San Diego, La Jolla, CA 92093-0319 (United States)

    2012-01-15

    We study the applicability of the model of hole superconductivity to materials. Both conventional and unconventional materials are considered. Many different classes of materials are discussed. The theory is found suitable to describe all of them. No other theory of superconductivity can describe all these classes of materials. The theory of hole superconductivity proposes that there is a single mechanism of superconductivity that applies to all superconducting materials. This paper discusses several material families where superconductivity occurs and how they can be understood within this theory. Materials discussed include the elements, transition metal alloys, high T{sub c} cuprates both hole-doped and electron-doped, MgB{sub 2}, iron pnictides and iron chalcogenides, doped semiconductors, and elements under high pressure.

  13. Mechanical Behaviour of Materials Volume II Fracture Mechanics and Damage

    CERN Document Server

    François, Dominique; Zaoui, André

    2013-01-01

    Designing new structural materials, extending lifetimes and guarding against fracture in service are among the preoccupations of engineers, and to deal with these they need to have command of the mechanics of material behaviour. This ought to reflect in the training of students. In this respect, the first volume of this work deals with elastic, elastoplastic, elastoviscoplastic and viscoelastic behaviours; this second volume continues with fracture mechanics and damage, and with contact mechanics, friction and wear. As in Volume I, the treatment links the active mechanisms on the microscopic scale and the laws of macroscopic behaviour. Chapter I is an introduction to the various damage phenomena. Chapter II gives the essential of fracture mechanics. Chapter III is devoted to brittle fracture, chapter IV to ductile fracture and chapter V to the brittle-ductile transition. Chapter VI is a survey of fatigue damage. Chapter VII is devoted to hydogen embrittlement and to environment assisted cracking, chapter VIII...

  14. Microstructures and mechanical properties of aging materials

    International Nuclear Information System (INIS)

    Liaw, P.K.; Viswanathan, R.; Murty, K.L.; Simonen, E.P.; Frear, D.

    1993-01-01

    This book contains a collection of papers presented at the symposium on ''Microstructures and Mechanical Properties of Aging Materials,'' that was held in Chicago, IL. November 2-5, 1992 in conjunction with the Fall Meeting of The Minerals, Metals and Materials Society (TMS). The subjects of interest in the symposium included: (1) mechanisms of microstructural degradation, (2) effects of microstructural degradation on mechanical behavior, (3) development of life prediction methodology for in-service structural and electronic components, (4) experimental techniques to monitor degradation of microstructures and mechanical properties, and (5) effects of environment on microstructural degradation and mechanical properties. Individual papers have been processed separately for inclusion in the appropriate data bases

  15. Tamarisk coalition - native riparian plant materials program

    Science.gov (United States)

    Stacy Kolegas

    2012-01-01

    The Tamarisk Coalition (TC), a nonprofit organization dedicated to riparian restoration in the western United States, has created a Native Plant Materials Program to address the identified need for native riparian plant species for use in revegetation efforts on the Colorado Plateau. The specific components of the Native Plant Materials Program include: 1) provide seed...

  16. Metallic materials for mechanical damping capacity applications

    Science.gov (United States)

    Crăciun, R. C.; Stanciu, S.; Cimpoeșu, R.; (Dragoș Ursanu, A. I.; Manole, V.; Paraschiv, P.; Chicet, D. L.

    2016-08-01

    Some metallic materials exhibit good damping capacity of mechanical energy into thermal energy. This property along with the others metallic characteristics make this materials interesting for a big number of applications. These materials can be used as bumpers in different applications including automotive field. Beside grey cast iron and shape memory alloys few new metallic materials are presented for the supposition of high damping capacity. We analyze the causes that increase the internal friction of some metallic materials and possibilities to enhance this property through different mechanical, physical or chemical methods. Shape memory alloys, especially those based on copper, present a different damping capacity on martensite, austenite or transition state. In the transformation range M ↔A, which in case of copper base shape memory alloys is quite large, the metallic intelligent materials present a high internal friction, almost comparable with natural rubber behavior that can transform mechanical energy into thermal energy till a certain value of the external solicitation. These materials can be used as noise or small vibrations bumpers or even as shock absorbers in automotive industry.

  17. Designing Competency-Based Materials for the Automotive Mechanics Curriculum

    Science.gov (United States)

    Richardson, Roger L.

    1977-01-01

    Describes the Career Education Center's (Florida State University) development of the "Automotive Mechanics Catalog" (a job inventory noting performance objectives for specific occupational programs), using the Vocational-Technical Education Consortium of States (V-TECS) model. Also describes the development of curriculum materials using…

  18. Gasoline Engine Mechanics. Florida Vocational Program Guide.

    Science.gov (United States)

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This vocational program guide is intended to assist in the organization, operation, and evaluation of a program in gasoline engine mechanics in school districts, area vocational centers, and community colleges. The following topics are covered: job duties of small-engine mechanics; program content (curriculum framework and student performance…

  19. Material removal mechanisms in electrochemical-mechanical polishing of tantalum

    International Nuclear Information System (INIS)

    Gao, F.; Liang, H.

    2009-01-01

    Material removal mechanisms in tantalum chemical-mechanical polishing (CMP) and electrochemical-mechanical polishing (ECMP) were investigated using the single frequency electrochemical impedance spectroscopy (EIS). Through measuring the impedance of the tantalum surface, the single frequency EIS scan made it possible to observe the CMP and ECMP processes in situ. The impedance results presented competing mechanisms of removal and formation of a surface oxide layer of tantalum. Analysis indicated that the thickness of the oxide layer formed during polishing was related to the mechanical power correlated to the friction force and the rotating speed. Furthermore, the rate of growth and removal of the oxide film was a function of the mechanical power. This understanding is beneficial for optimization of CMP and ECMP processes.

  20. Mechanics of materials formulas and problems : engineering mechanics 2

    CERN Document Server

    Gross, Dietmar; Wriggers, Peter; Schröder, Jörg; Müller, Ralf

    2017-01-01

    This book contains the most important formulas and more than 140 completely solved problems from Mechanics of Materials and Hydrostatics. It provides engineering students material to improve their skills and helps to gain experience in solving engineering problems. Particular emphasis is placed on finding the solution path and formulating the basic equations. Topics include: - Stress - Strain - Hooke’s Law - Tension and Compression in Bars - Bending of Beams - Torsion - Energy Methods - Buckling of Bars - Hydrostatics .

  1. Materials for water pump mechanical seals

    International Nuclear Information System (INIS)

    Brousse, P.

    1992-01-01

    In view of the continually increasing power ratings of conventional and nuclear power plants and the related reliability and safety problems, plant builders have had to develop seal systems compatible with current water pump performances. In 1970, EDF/R and DD was already concerned by this problem. It soon became obvious that the nature of the materials used for the friction surfaces was decisive for seal durability. Exceptional loads (transients, high vibration levels, etc...) hasten aging. To begin with, friction surfaces consisted of a hard material (tungsten carbide) mated with a soft material (carbon). Resistance was unpredictable and not compatible with industrial requirements. Tests performed on the EDF/R and DD test benches evidenced the same types of degradation. The mechanical seal manufacturers then began to use ceramic materials (silicon carbide), which raised high expectations. Unfortunately, these were recent materials and their manufacturing process was not thoroughly understood. Hopes were soon dashed in many applications, including that of mechanical seals. Fluctuating results were obtained over the next few years. The raw material suppliers made progress, especially with regard to reducing fragility. On a parallel, the mechanical seal manufacturers initiated comparative tests on the friction resistance of materials. It has also been established that ceramics have to be stringently supervised at all levels: part design, inspection, assembly, use. EDF has much insisted that mechanical seal suppliers guarantee the constant quality of their products. EDF/R and DD has systematically tested new sensitive devices, under normal and exceptional conditions, prior to their installation at the plants. At the present time, the silicon carbides proposed by the mechanical seal suppliers are entirely satisfactory. The carbon mating surface was far less problematic. The required reliability was obtained by replacing resin binder carbons by the more resistant

  2. Materials program plan for inertial confinement fusion

    International Nuclear Information System (INIS)

    Garde, A.; Hall, B.O.; Harkness, S.D.; Maiya, P.S.; Rechtin, M.D.; Li, C.Y.

    1979-08-01

    The effect of the irradiation environment on the microstructure of materials is studied. A major part of the initial activity in this area will be aimed toward evaluating the importance of pulse effects on microstructural development. The development effort that is necessary to cope with the high cycle loading of the first wall structure is studied. The loading pulses are expected to range from 1 to 20 per second (3 x 10 7 to 6 x 10 8 /year), thus creating a high cycle fatigue problem for any long-lived first wall structure. The interrelationship between specimen and component testing is a major issue in this section. Static mechanical property requirements are also considered here. Lithium compatibility is treated. The final section integrates the conclusions reached in the body of the report into a unified strategy that suggests a particular effort level to support major program milestones

  3. Materials program plan for inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Garde, A.; Hall, B.O.; Harkness, S.D.; Maiya, P.S.; Rechtin, M.D.; Li, C.Y.

    1979-08-01

    The effect of the irradiation environment on the microstructure of materials is studied. A major part of the initial activity in this area will be aimed toward evaluating the importance of pulse effects on microstructural development. The development effort that is necessary to cope with the high cycle loading of the first wall structure is studied. The loading pulses are expected to range from 1 to 20 per second (3 x 10/sup 7/ to 6 x 10/sup 8//year), thus creating a high cycle fatigue problem for any long-lived first wall structure. The interrelationship between specimen and component testing is a major issue in this section. Static mechanical property requirements are also considered here. Lithium compatibility is treated. The final section integrates the conclusions reached in the body of the report into a unified strategy that suggests a particular effort level to support major program milestones.

  4. Advanced quantum mechanics materials and photons

    CERN Document Server

    Dick, Rainer

    2016-01-01

    In this updated and expanded second edition of a well-received and invaluable textbook, Prof. Dick emphasizes the importance of advanced quantum mechanics for materials science and all experimental techniques which employ photon absorption, emission, or scattering. Important aspects of introductory quantum mechanics are covered in the first seven chapters to make the subject self-contained and accessible for a wide audience. Advanced Quantum Mechanics, Materials and Photons can therefore be used for advanced undergraduate courses and introductory graduate courses which are targeted towards students with diverse academic backgrounds from the Natural Sciences or Engineering. To enhance this inclusive aspect of making the subject as accessible as possible Appendices A and B also provide introductions to Lagrangian mechanics and the covariant formulation of electrodynamics. This second edition includes an additional 62 new problems as well as expanded sections on relativistic quantum fields and applications of�...

  5. Advanced quantum mechanics materials and photons

    CERN Document Server

    Dick, Rainer

    2012-01-01

    Advanced Quantum Mechanics: Materials and Photons is a textbook which emphasizes the importance of advanced quantum mechanics for materials science and all experimental techniques which employ photon absorption, emission, or scattering. Important aspects of introductory quantum mechanics are covered in the first seven chapters to make the subject self-contained and accessible for a wide audience. The textbook can therefore be used for advanced undergraduate courses and introductory graduate courses which are targeted towards students with diverse academic backgrounds from the Natural Sciences or Engineering. To enhance this inclusive aspect of making the subject as accessible as possible, Appendices A and B also provide introductions to Lagrangian mechanics and the covariant formulation of electrodynamics. Other special features include an introduction to Lagrangian field theory and an integrated discussion of transition amplitudes with discrete or continuous initial or final states. Once students have acquir...

  6. Mathematics and Mechanics of Granular Materials

    CERN Document Server

    Hill, James M

    2005-01-01

    Granular or particulate materials arise in almost every aspect of our lives, including many familiar materials such as tea, coffee, sugar, sand, cement and powders. At some stage almost every industrial process involves a particulate material, and it is usually the cause of the disruption to the smooth running of the process. In the natural environment, understanding the behaviour of particulate materials is vital in many geophysical processes such as earthquakes, landslides and avalanches. This book is a collection of current research from some of the major contributors in the topic of modelling the behaviour of granular materials. Papers from every area of current activity are included, such as theoretical, numerical, engineering and computational approaches. This book illustrates the numerous diverse approaches to one of the outstanding problems of modern continuum mechanics.

  7. Materials sciences programs, Fiscal year 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-10-01

    The Division of Materials Sciences is responsible for basic research and research facilities in materials science topics important to the mission of the Department of Energy. The programmatic divisions under the Office of Basic Energy Sciences are Chemical Sciences, Engineering and Geosciences, and Energy Biosciences. Materials Science is an enabling technology. The performance parameters, economics, environmental acceptability and safety of all energy generation, conversion, transmission and conservation technologies are limited by the properties and behavior of materials. The Materials Sciences programs develop scientific understanding of the synergistic relationship among synthesis, processing, structure, properties, behavior, performance and other characteristics of materials. Emphasis is placed on the development of the capability to discover technologically, economically, and environmentally desirable new materials and processes, and the instruments and national user facilities necessary for achieving such progress. Materials Sciences subfields include: physical metallurgy, ceramics, polymers, solid state and condensed matter physics, materials chemistry, surface science and related disciplines where the emphasis is on the science of materials. This report includes program descriptions for 517 research programs including 255 at 14 DOE National Laboratories, 262 research grants (233 of which are at universities), and 29 Small Business Innovation Research Grants. Five cross-cutting indices located at the rear of this book identify all 517 programs according to principal investigator(s), materials, techniques, phenomena, and environment.

  8. Mechanics of composite materials: Unified micromechanical approach

    International Nuclear Information System (INIS)

    Aboundi, J.

    1991-01-01

    Although many books have been written on the mechanics of composite materials, only a vew few have been devoted almost exclusively to the micromechanics aspects. The present monograph is devoted primarily to the micromechanics of fiber and particle reinforced composites with some additional treatment of laminates as well. Thus, this book would probably be more suitable as a reference book than a textbook

  9. Mechanical exfoliation of two-dimensional materials

    Science.gov (United States)

    Gao, Enlai; Lin, Shao-Zhen; Qin, Zhao; Buehler, Markus J.; Feng, Xi-Qiao; Xu, Zhiping

    2018-06-01

    Two-dimensional materials such as graphene and transition metal dichalcogenides have been identified and drawn much attention over the last few years for their unique structural and electronic properties. However, their rise begins only after these materials are successfully isolated from their layered assemblies or adhesive substrates into individual monolayers. Mechanical exfoliation and transfer are the most successful techniques to obtain high-quality single- or few-layer nanocrystals from their native multi-layer structures or their substrate for growth, which involves interfacial peeling and intralayer tearing processes that are controlled by material properties, geometry and the kinetics of exfoliation. This procedure is rationalized in this work through theoretical analysis and atomistic simulations. We propose a criterion to assess the feasibility for the exfoliation of two-dimensional sheets from an adhesive substrate without fracturing itself, and explore the effects of material and interface properties, as well as the geometrical, kinetic factors on the peeling behaviors and the torn morphology. This multi-scale approach elucidates the microscopic mechanism of the mechanical processes, offering predictive models and tools for the design of experimental procedures to obtain single- or few-layer two-dimensional materials and structures.

  10. Sandia Dynamic Materials Program Strategic Plan.

    Energy Technology Data Exchange (ETDEWEB)

    Flicker, Dawn Gustine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Benage, John F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Desjarlais, Michael P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Knudson, Marcus D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Leifeste, Gordon T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lemke, Raymond W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mattsson, Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wise, Jack L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    Materials in nuclear and conventional weapons can reach multi-megabar pressures and 1000s of degree temperatures on timescales ranging from microseconds to nanoseconds. Understanding the response of complex materials under these conditions is important for designing and assessing changes to nuclear weapons. In the next few decades, a major concern will be evaluating the behavior of aging materials and remanufactured components. The science to enable the program to underwrite decisions quickly and confidently on use, remanufacturing, and replacement of these materials will be critical to NNSA’s new Stockpile Responsiveness Program. Material response is also important for assessing the risks posed by adversaries or proliferants. Dynamic materials research, which refers to the use of high-speed experiments to produce extreme conditions in matter, is an important part of NNSA’s Stockpile Stewardship Program.

  11. Mechanical properties of structural materials in HLM

    International Nuclear Information System (INIS)

    Moisa, A. E.; Valeca, S.; Pitigoi, V.

    2016-01-01

    The Generation IV nuclear systems are nowadays in the design stage, and this is one of the reasons of testing stage for candidate materials. The purpose of this paper is to present the tensile tests, for candidate materials. The studied test are: on temperature of 500°C in air, on mechanical testing machine Walter + Bie by using the furnace of the testing machine, and environmental molten lead using testing machine Instron, equipped with a lead testing device attached to it. Also the mechanical parameters will be determined on tensile strength and yield strength for steel 316L material to be used as candidate in achieving LFR reactor vessel type, and the microstructural analysis of surface breaking will be performed by electronic microscopy. The paper will present the main components, the operating procedure of the testing system, and the results of tensile tests in molten lead. (authors)

  12. Teaching Continuum Mechanics in a Mechanical Engineering Program

    Science.gov (United States)

    Liu, Yucheng

    2011-01-01

    This paper introduces a graduate course, continuum mechanics, which is designed for and taught to graduate students in a Mechanical Engineering (ME) program. The significance of continuum mechanics in engineering education is demonstrated and the course structure is described. Methods used in teaching this course such as topics, class…

  13. Silicon as an anisotropic mechanical material

    DEFF Research Database (Denmark)

    Thomsen, Erik Vilain; Reck, Kasper; Skands, Gustav Erik

    2014-01-01

    While silicon is an anisotropic material it is often in literature treated as an isotropic material when it comes to plate calculations. This leads to considerable errors in the calculated deflection. To overcome this problem, we present an in-depth analysis of the bending behavior of thin crysta...... analytical models involving crystalline plates, such as those often found in the field of micro electro mechanical systems. The effect of elastic boundary conditions is taken into account by using an effective radius of the plate....

  14. Unify a hazardous materials/waste program

    International Nuclear Information System (INIS)

    Carson, H.T.

    1988-01-01

    Efficiently managing a hazardous materials/waste program in a multi-facility, multi-product corporation is a major challenge. This paper describes several methods to help unify a program and gain maximum efficiency of manpower and to minimize risk

  15. Bibliography of Ethnic Heritage Studies Program Materials.

    Science.gov (United States)

    Kotler, Greta; And Others

    The Ethnic Heritage Studies Program was designed to teach students about the nature of their heritage and to study the contributions of the cultural heritage of other ethnic groups. This is a bibliography of materials developed by projects which received Federal Ethnic Heritage Studies Program grants during fiscal year 1974-75 and 1975-76.…

  16. Basic Automotive Mechanics. Florida Vocational Program Guide.

    Science.gov (United States)

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This program guide identifies primary concerns in the organization, operation, and evaluation of a basic automotive mechanics program. It is designed for local school district and community college administrators, instructors, program advisory committees, and regional coordinating councils. The guide begins with the Dictionary of Occupational…

  17. Materials sciences programs: Fiscal year 1994

    Science.gov (United States)

    1995-04-01

    The Division of Materials Sciences is located within the DOE in the Office of Basic Energy Sciences. The Division of Materials Sciences is responsible for basic research and research facilities in strategic materials science topics of critical importance to the mission of the Department and its Strategic Plan. Materials Science is an enabling technology. The performance parameters, economics, environmental acceptability and safety of all energy generation, conversion, transmission and conservation technologies are limited by the properties and behavior of materials. The Materials Sciences programs develop scientific understanding of the synergistic relationship amongst the synthesis, processing, structure, properties, behavior, performance and other characteristics of materials. Emphasis is placed on the development of the capability to discover technologically, economically, and environmentally desirable new materials and processes, and the instruments and national user facilities necessary for achieving such progress. Materials Sciences sub-fields include physical metallurgy, ceramics, polymers, solid state and condensed matter physics, materials chemistry, surface science and related disciplines where the emphasis is on the science of materials. This report includes program descriptions for 458 research programs including 216 at 14 DOE National Laboratories, 242 research grants (233 for universities), and 9 Small Business Innovation Research (SBIR) Grants. The report is divided into eight sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the SBIR Program, Section D describes the Center of Excellence for the Synthesis and Processing of Advanced Materials and E has information on major user facilities. F contains descriptions of other user facilities; G, a summary of funding levels; and H, indices characterizing research projects.

  18. Materials sciences programs, fiscal year 1994

    International Nuclear Information System (INIS)

    1995-04-01

    The Division of Materials Sciences is located within the DOE in the Office of Basic Energy Sciences. The Division of Materials Sciences is responsible for basic research and research facilities in strategic materials science topics of critical importance to the mission of the Department and its Strategic Plan. Materials Science is an enabling technology. The performance parameters, economics, environmental acceptability and safety of all energy generation, conversion, transmission and conservation technologies are limited by the properties and behavior of materials. The Materials Sciences programs develop scientific understanding of the synergistic relationship amongst the synthesis, processing, structure, properties, behavior, performance and other characteristics of materials. Emphasis is placed on the development of the capability to discover technologically, economically, and environmentally desirable new materials and processes, and the instruments and national user facilities necessary for achieving such progress. Materials Sciences sub-fields include physical metallurgy, ceramics, polymers, solid state and condensed matter physics, materials chemistry, surface science and related disciplines where the emphasis is on the science of materials. This report includes program descriptions for 458 research programs including 216 at 14 DOE National Laboratories, 242 research grants (233 for universities), and 9 Small Business Innovation Research (SBIR) Grants. The report is divided into eight sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the SBIR Program, Section D describes the Center of Excellence for the Synthesis and Processing of Advanced Materials and E has information on major user facilities. F contains descriptions of other user facilities; G, a summary of funding levels; and H, indices characterizing research projects

  19. Materials sciences programs, fiscal year 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The Division of Materials Sciences is located within the DOE in the Office of Basic Energy Sciences. The Division of Materials Sciences is responsible for basic research and research facilities in strategic materials science topics of critical importance to the mission of the Department and its Strategic Plan. Materials Science is an enabling technology. The performance parameters, economics, environmental acceptability and safety of all energy generation, conversion, transmission and conservation technologies are limited by the properties and behavior of materials. The Materials Sciences programs develop scientific understanding of the synergistic relationship amongst the synthesis, processing, structure, properties, behavior, performance and other characteristics of materials. Emphasis is placed on the development of the capability to discover technologically, economically, and environmentally desirable new materials and processes, and the instruments and national user facilities necessary for achieving such progress. Materials Sciences sub-fields include physical metallurgy, ceramics, polymers, solid state and condensed matter physics, materials chemistry, surface science and related disciplines where the emphasis is on the science of materials. This report includes program descriptions for 458 research programs including 216 at 14 DOE National Laboratories, 242 research grants (233 for universities), and 9 Small Business Innovation Research (SBIR) Grants. The report is divided into eight sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the SBIR Program, Section D describes the Center of Excellence for the Synthesis and Processing of Advanced Materials and E has information on major user facilities. F contains descriptions of other user facilities; G, a summary of funding levels; and H, indices characterizing research projects.

  20. Measurement control program for nuclear material accounting

    International Nuclear Information System (INIS)

    Brouns, R.J.; Roberts, F.P.; Merrill, J.A.; Brown, W.B.

    1980-06-01

    A measurement control program for nuclear material accounting monitors and controls the quality of the measurments of special nuclear material that are involved in material balances. The quality is monitored by collecting data from which the current precision and accuracy of measurements can be evaluated. The quality is controlled by evaluations, reviews, and other administrative measures for control of selection or design of facilities, equipment and measurement methods and the training and qualification of personnel who perform SNM measurements. This report describes the most important elements of a program by which management can monitor and control measurement quality

  1. Material modeling of biofilm mechanical properties.

    Science.gov (United States)

    Laspidou, C S; Spyrou, L A; Aravas, N; Rittmann, B E

    2014-05-01

    A biofilm material model and a procedure for numerical integration are developed in this article. They enable calculation of a composite Young's modulus that varies in the biofilm and evolves with deformation. The biofilm-material model makes it possible to introduce a modeling example, produced by the Unified Multi-Component Cellular Automaton model, into the general-purpose finite-element code ABAQUS. Compressive, tensile, and shear loads are imposed, and the way the biofilm mechanical properties evolve is assessed. Results show that the local values of Young's modulus increase under compressive loading, since compression results in the voids "closing," thus making the material stiffer. For the opposite reason, biofilm stiffness decreases when tensile loads are imposed. Furthermore, the biofilm is more compliant in shear than in compression or tension due to the how the elastic shear modulus relates to Young's modulus. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Computational Materials Program for Alloy Design

    Science.gov (United States)

    Bozzolo, Guillermo

    2005-01-01

    The research program sponsored by this grant, "Computational Materials Program for Alloy Design", covers a period of time of enormous change in the emerging field of computational materials science. The computational materials program started with the development of the BFS method for alloys, a quantum approximate method for atomistic analysis of alloys specifically tailored to effectively deal with the current challenges in the area of atomistic modeling and to support modern experimental programs. During the grant period, the program benefited from steady growth which, as detailed below, far exceeds its original set of goals and objectives. Not surprisingly, by the end of this grant, the methodology and the computational materials program became an established force in the materials communitiy, with substantial impact in several areas. Major achievements during the duration of the grant include the completion of a Level 1 Milestone for the HITEMP program at NASA Glenn, consisting of the planning, development and organization of an international conference held at the Ohio Aerospace Institute in August of 2002, finalizing a period of rapid insertion of the methodology in the research community worlwide. The conference, attended by citizens of 17 countries representing various fields of the research community, resulted in a special issue of the leading journal in the area of applied surface science. Another element of the Level 1 Milestone was the presentation of the first version of the Alloy Design Workbench software package, currently known as "adwTools". This software package constitutes the first PC-based piece of software for atomistic simulations for both solid alloys and surfaces in the market.Dissemination of results and insertion in the materials community worldwide was a primary focus during this period. As a result, the P.I. was responsible for presenting 37 contributed talks, 19 invited talks, and publishing 71 articles in peer-reviewed journals, as

  3. Dynamic mechanical properties of buffer material

    International Nuclear Information System (INIS)

    Takaji, Kazuhiko; Taniguchi, Wataru

    1999-11-01

    The buffer material is expected to maintain its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. over a long period of time. Natural clay is mentioned as a material that can relatively satisfy above. Among the kinds of natural clay, bentonite when compacted is superior because (i) it has exceptionally low water permeability and properties to control the movement of water in buffer, (ii) it fills void spaces in the buffer and fractures in the host rock as it swells upon water uptake, (iii) it has the ability to exchange cations and to adsorb cationic radioelements. In order to confirm these functions for the purpose of safety assessment, it is necessary to evaluate buffer properties through laboratory tests and engineering-scale tests, and to make assessments based on the ranges in the data obtained. This report describes the procedures, test conditions, results and examinations on the buffer material of dynamic triaxial tests, measurement of elastic wave velocity and liquefaction tests that aim at getting hold of dynamic mechanical properties. We can get hold of dependency on the shearing strain of the shearing modulus and hysteresis damping constant, the application for the mechanical model etc. by dynamic triaxial tests, the acceptability of maximum shearing modulus obtained from dynamic triaxial tests etc. by measurement of elastic wave velocity and dynamic strength caused by cyclic stress etc. by liquefaction tests. (author)

  4. Measurement of material mechanical properties in microforming

    Science.gov (United States)

    Yun, Wang; Xu, Zhenying; Hui, Huang; Zhou, Jianzhong

    2006-02-01

    As the rapid market need of micro-electro-mechanical systems engineering gives it the wide development and application ranging from mobile phones to medical apparatus, the need of metal micro-parts is increasing gradually. Microforming technology challenges the plastic processing technology. The findings have shown that if the grain size of the specimen remains constant, the flow stress changes with the increasing miniaturization, and also the necking elongation and the uniform elongation etc. It is impossible to get the specimen material properties in conventional tensile test machine, especially in the high precision demand. Therefore, one new measurement method for getting the specimen material-mechanical property with high precision is initiated. With this method, coupled with the high speed of Charge Coupled Device (CCD) camera and high precision of Coordinate Measuring Machine (CMM), the elongation and tensile strain in the gauge length are obtained. The elongation, yield stress and other mechanical properties can be calculated from the relationship between the images and CCD camera movement. This measuring method can be extended into other experiments, such as the alignment of the tool and specimen, micro-drawing process.

  5. Rock mechanics contributions from defense programs

    International Nuclear Information System (INIS)

    Heuze, F.E.

    1992-02-01

    An attempt is made at illustrating the many contributions to rock mechanics from US defense programs, over the past 30-plus years. Large advances have been achieved in the technology-base area covering instrumentation, material properties, physical modeling, constitutive relations and numerical simulations. In the applications field, much progress has been made in understanding and being able to predict rock mass behavior related to underground explosions, cratering, projectile penetration, and defense nuclear waste storage. All these activities stand on their own merit as benefits to national security. But their impact is even broader, because they have found widespread applications in the non-defense sector; to name a few: the prediction of the response of underground structures to major earthquakes, the physics of the earth's interior at great depths, instrumentation for monitoring mine blasting, thermo-mechanical instrumentation useful for civilian nuclear waste repositories, dynamic properties of earthquake faults, and transient large-strain numerical modeling of geological processes, such as diapirism. There is not pretense that this summary is exhaustive. It is meant to highlight success stories representative of DOE and DOD geotechnical activities, and to point to remaining challenges

  6. Compressive Failure Mechanisms in Layered Materials

    DEFF Research Database (Denmark)

    Sørensen, Kim Dalsten

    Two important failure modes in fiber reinforced composite materials in cluding layers and laminates occur under loading conditions dominated by compression in the layer direction. These two distinctly different failure modes are 1. buckling driven delamination 2. failure by strain localization...... or on cylindrical substrates modeling the delamination as an interface fracture mechanical problem. Here attention is directed towards double-curved substrates, which introduces a new non-dimensional combination of geometric parameters. It is shown for a wide range of parameters that by choosing the two....... This has some impact on the convergence rate for decreasing mesh size in the load vs. end shortening response for a rectangular block of material. Especially in the immediate post critical range the convergence rate may be slow. The capabilities of the model to deal with more complicated structural...

  7. Materials sciences programs: Fiscal year 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    The purpose of this report is to provide a convenient compilation and index of the DOE Materials Science Division programs. This compilation is primarily intended for use by administrators, managers, and scientists to help coordinate research. The report is divided into eight sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the Small Business Innovation Research Program, Section D describes the Center of Excellence for the Synthesis and Processing of Advanced Materials and E has information on major user facilities. F describes other user facilities, G as a summary of funding levels and H has indices characterizing research projects.

  8. Materials sciences programs fiscal year 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The purpose of this report is to provide a convenient compilation and index of the DOE Materials Sciences Division programs. This compilation is primarily intended for use by administrators, managers, and scientists to help coordinate research. The report is divided into eight sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the Small Business Innovation Research Program, Section D describes the Center of Excellence for the Synthesis and Processing of Advanced Materials and E has information on major user facilities. F describes other user facilities, G as a summary of funding levels and H has indices characterizing research projects.

  9. Materials Sciences programs, fiscal year 1986

    International Nuclear Information System (INIS)

    1986-09-01

    Purpose of this report is to provide a convenient compilation and index of the DOE Materials Sciences Division programs. The report is divided into six sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the Small Business Innovation Research Program, Sections D and E have information on DOE collaborative research centers, Section F gives distribution of funding, and Section G has various indexes

  10. Materials Sciences programs, Fiscal Year 1984

    International Nuclear Information System (INIS)

    1984-09-01

    This report provides a convenient compilation and index of the DOE Materials Sciences Division programs. The report is divided into six sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the Small Business Innovation Research program, Section D has information on DOE collaborative research centers, Section E gives distributions of funding, and Section F has various indexes

  11. Materials Sciences programs, Fiscal Year 1992

    International Nuclear Information System (INIS)

    1993-02-01

    The Materials Sciences Division supports basic research on materials properties and phenomena important to all energy systems. This report contains a listing of research underway in FY 1992 together with an index to the Division's programs. Recent publications from Division-sponsored panel meetings and workshops are listed. The body of the report is arranged under the following section headings: laboratories, grant and contract research, small business innovation research, major user facilities, other user facilities, funding levels, and index

  12. Mechanism of lead removal by waste materials

    International Nuclear Information System (INIS)

    Qaiser, S.; Saleemi, A.R.; Ahmed, M.M.

    2007-01-01

    Heavy metal ions are priority pollutants, due to their toxicity and mobility in natural water ecosystems. The discharge of heavy metals into aquatic ecosystems has become a matter of concern in Pakistan over the last few decades. These contaminants are introduced into the aquatic systems significantly as a result of various industrial operations. The metals of concern include lead, chromium, zinc, copper, nickel and uranium. Lead is one of the most hazardous and toxic metals. It is used as industrial raw material in the manufacture of storage batteries, pigments, leaded glass, fuels, photographic materials, matches and explosives. Conventional methods for treatment of dissolved lead include precipitation, adsorption, coagulation/notation, sedimentation, reverse osmosis and ion exchange. Each process has its merits and limitations in applications. Adsorption by activated carbon and ion exchange using commercial ion exchange resins are very expensive processes, especially for a developing country like Pakistan. The present research was conducted to identify some waste materials, which can be utilized to remove lead from industrial wastewater. Natural wastes in the form of leaves and ash have considerable amounts of CaO, MgO, Na/sub 2/O, SiO/sub 2/ and Al/sub 2/O/sub 3/ which can be utilized for precipitation and adsorption. Utilization of waste materials to remove lead from industrial wastewater is the basic theme of this research. The waste materials used in this research were maple leaves, pongamia pinata leaves, coal ash and maple ago leave ash. Parameters studied were reaction time, precipitant dose, pH and temperature. It was found that maple leaves ash has maximum lead removal capacity 19.24 mg g/sup -1/ followed by coal ash 13.2 mg g/sup -1/. The optimal pH was 5 for maple leaves and pongamia Pinata leaves; and 4 for coal ash and maple leaves ash. Removal capacity decreased with increase in temperature. The major removal mechanisms were adsorption and

  13. Mechanical degradation temperature of waste storage materials

    International Nuclear Information System (INIS)

    Fink, M.C.; Meyer, M.L.

    1993-01-01

    Heat loading analysis of the Solid Waste Disposal Facility (SWDF) waste storage configurations show the containers may exceed 90 degrees C without any radioactive decay heat contribution. Contamination containment is primarily controlled in TRU waste packaging by using multiple bag layers of polyvinyl chloride and polyethylene. Since literature values indicate that these thermoplastic materials can begin mechanical degradation at 66 degrees C, there was concern that the containment layers could be breached by heating. To better define the mechanical degradation temperature limits for the materials, a series of heating tests were conducted over a fifteen and thirty minute time interval. Samples of a low-density polyethylene (LDPE) bag, a high-density polyethylene (HDPE) high efficiency particulate air filter (HEPA) container, PVC bag and sealing tape were heated in a convection oven to temperatures ranging from 90 to 185 degrees C. The following temperature limits are recommended for each of the tested materials: (1) low-density polyethylene -- 110 degrees C; (2) polyvinyl chloride -- 130 degrees C; (3) high-density polyethylene -- 140 degrees C; (4) sealing tape -- 140 degrees C. Testing with LDPE and PVC at temperatures ranging from 110 to 130 degrees C for 60 and 120 minutes also showed no observable differences between the samples exposed at 15 and 30 minute intervals. Although these observed temperature limits differ from the literature values, the trend of HDPE having a higher temperature than LDPE is consistent with the reference literature. Experimental observations indicate that the HDPE softens at elevated temperatures, but will retain its shape upon cooling. In SWDF storage practices, this might indicate some distortion of the waste container, but catastrophic failure of the liner due to elevated temperatures (<185 degrees C) is not anticipated

  14. Mechanical properties of nanostructure of biological materials

    Science.gov (United States)

    Ji, Baohua; Gao, Huajian

    2004-09-01

    Natural biological materials such as bone, teeth and nacre are nanocomposites of protein and mineral with superior strength. It is quite a marvel that nature produces hard and tough materials out of protein as soft as human skin and mineral as brittle as classroom chalk. What are the secrets of nature? Can we learn from this to produce bio-inspired materials in the laboratory? These questions have motivated us to investigate the mechanics of protein-mineral nanocomposite structure. Large aspect ratios and a staggered alignment of mineral platelets are found to be the key factors contributing to the large stiffness of biomaterials. A tension-shear chain (TSC) model of biological nanostructure reveals that the strength of biomaterials hinges upon optimizing the tensile strength of the mineral crystals. As the size of the mineral crystals is reduced to nanoscale, they become insensitive to flaws with strength approaching the theoretical strength of atomic bonds. The optimized tensile strength of mineral crystals thus allows a large amount of fracture energy to be dissipated in protein via shear deformation and consequently enhances the fracture toughness of biocomposites. We derive viscoelastic properties of the protein-mineral nanostructure and show that the toughness of biocomposite can be further enhanced by the viscoelastic properties of protein.

  15. Materials Sciences programs, Fiscal Year 1983

    International Nuclear Information System (INIS)

    1983-09-01

    The Materials Sciences Division constitutes one portion of a wide range of research supported by the DOE Office of Basic Energy Sciences. This report contains a listing of research underway in FY 1983 together with a convenient index to the program

  16. Materials Sciences programs, Fiscal year 1993

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-01

    This report provides a compilation and index of the DOE Materials Sciences Division programs; the compilation is to assist administrators, managers, and scientists to help coordinate research. The report is divided into 7 sections: laboratory projects, contract research projects, small business innovation research, major user facilities, other user facilities, funding level distributions, and indexes.

  17. Tune Up: Automotive Mechanics Instructional Program. Block 5.

    Science.gov (United States)

    O'Brien, Ralph D.

    The fifth of six instructional blocks in automotive mechanics, the lessons and supportive information in the document provide a guide for teachers in planning an instructional program in automotive tune-ups at the secondary and post secondary level. The material, as organized, is a suggested sequence of instruction within each block. Each lesson…

  18. Fuel System: Automotive Mechanics Instructional Program. Block 4.

    Science.gov (United States)

    O'Brien, Ralph D.

    The fourth of six instructional blocks in automotive mechanics, the lessons and supportive information in the document provide a guide for teachers in planning an instructional program in automotive fuel systems at the secondary and post secondary level. The material, as organized, is a suggested sequence of instruction within each block. Each…

  19. Cooling System: Automotive Mechanics Instructional Program. Block 6.

    Science.gov (United States)

    O'Brien, Ralph D.

    The last of six instructional blocks in automotive mechanics, the lessons and supportive information in the document provide a guide for teachers in planning an instructional program in the automotive cooling system at the secondary and post secondary level. The material, as organized, is a suggested sequence of instruction within each block. Each…

  20. Engine Fundamentals: Automotive Mechanics Instructional Program. Block 2.

    Science.gov (United States)

    O'Brien, Ralph D.

    The second of six instructional blocks in automotive mechanics, the lessons and supportive information in the document provide a guide for teachers in planning an instructional program in engine fundamentals at the secondary and postsecondary level. The material, as organized, is a suggested sequence of instruction within each block. Each lesson…

  1. Thermoelectric materials evaluation program. Quarterly technical task report No. 46

    International Nuclear Information System (INIS)

    Hampl, E.F. Jr.

    1976-02-01

    This forty-sixth Technical Task Report prepared under contract E(11-1)-2331 with the U.S. AEC and U.S. ERDA covers the performance period from October 1, 1975, to December 31, 1975. Highlights include the following tasks: N-type material development (material synthesis--gadolinium selenide compositions; material analyses; material processing; element contacting; ingradient compatibility and life testing; mechanical property characterization), TPM-217 P-type characterization (material preparation and analyses; element contacting; thermodynamic stability; isothermal chemical compatibility; ingradient compatibility and ingradient life testing; performance mapping of contacted and noncontacted elements; high-temperature partitioned P-legs), couple development (design and development of TPM-217/gadolinium selenide rare earth chalcogenide couple; design and development of TPM-217/3N-PbTe couples; advanced generator concepts), module development, liaison with Jet Propulsion Laboratory and material supply, liaison with GGA, and program management. 24 figures, 27 tables

  2. Static mechanical properties of buffer material

    International Nuclear Information System (INIS)

    Takaji, Kazuhiko; Suzuki, Hideaki

    1999-11-01

    The buffer material is expected to maintain its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. over a long period of time. Natural clay is mentioned as a material that can relatively satisfy above. Among the kinds of natural clay, bentonite when compacted is superior because (i) it has exceptionally low water permeability and properties to control the movement of water in buffer, (ii) it fills void spaces in the buffer and fractures in the host rock as it swells upon water uptake, (iii) it has the ability to exchange cations and to adsorb cationic radioelements. In order to confirm these functions for the purpose of safety assessment, it is necessary to evaluate buffer properties through laboratory tests and engineering-scale tests, and to make assessments based on the ranges in the data obtained. This report describes the procedures, test conditions, results and examinations on the buffer material of unconfined compression tests, one-dimensional consolidation tests, consolidated-undrained triaxial compression tests and consolidated-undrained triaxial creep tests that aim at getting hold of static mechanical properties. We can get hold of the relationship between the dry density and tensile stress etc. by Brazilian tests, between the dry density and unconfined compressive strength etc. by unconfined compression tests, between the consolidation stress and void ratio etc. by one-dimensional consolidation tests, the stress pass of each effective confining pressure etc. by consolidated-undrained triaxial compression tests and the axial strain rate with time of each axial stress etc. by consolidated-undrained triaxial creep tests. (author)

  3. Mechanical properties of low dimensional materials

    Science.gov (United States)

    Saini, Deepika

    Recent advances in low dimensional materials (LDMs) have paved the way for unprecedented technological advancements. The drive to reduce the dimensions of electronics has compelled researchers to devise newer techniques to not only synthesize novel materials, but also tailor their properties. Although micro and nanomaterials have shown phenomenal electronic properties, their mechanical robustness and a thorough understanding of their structure-property relationship are critical for their use in practical applications. However, the challenges in probing these mechanical properties dramatically increase as their dimensions shrink, rendering the commonly used techniques inadequate. This dissertation focuses on developing techniques for accurate determination of elastic modulus of LDMs and their mechanical responses under tensile and shear stresses. Fibers with micron-sized diameters continuously undergo tensile and shear deformations through many phases of their processing and applications. Significant attention has been given to their tensile response and their structure-tensile properties relations are well understood, but the same cannot be said about their shear responses or the structure-shear properties. This is partly due to the lack of appropriate instruments that are capable of performing direct shear measurements. In an attempt to fill this void, this dissertation describes the design of an inexpensive tabletop instrument, referred to as the twister, which can measure the shear modulus (G) and other longitudinal shear properties of micron-sized individual fibers. An automated system applies a pre-determined twist to the fiber sample and measures the resulting torque using a sensitive optical detector. The accuracy of the instrument was verified by measuring G for high purity copper and tungsten fibers. Two industrially important fibers, IM7 carbon fiber and KevlarRTM 119, were found to have G = 17 and 2.4 GPa, respectively. In addition to measuring the shear

  4. Navy Shipboard Hazardous Material Minimization Program

    Energy Technology Data Exchange (ETDEWEB)

    Bieberich, M.J. [Naval Surface Warfare Center, Annapolis, MD (United States). Carderock Div.; Robinson, P. [Life Cycle Engineering, Inc., Charleston, SC (United States); Chastain, B.

    1994-12-31

    The use of hazardous (and potentially hazardous) materials in shipboard cleaning applications has proliferated as new systems and equipments have entered the fleet to reside alongside existing equipments. With the growing environmental awareness (and additional, more restrictive regulations) at all levels/echelon commands of the DoD, the Navy has initiated a proactive program to undertake the minimization/elimination of these hazardous materials in order to eliminate HMs at the source. This paper will focus on the current Shipboard Hazardous Materials Minimization Program initiatives including the identification of authorized HM currently used onboard, identification of potential substitute materials for HM replacement, identification of new cleaning technologies and processes/procedures, and identification of technical documents which will require revision to eliminate the procurement of HMs into the federal supply system. Also discussed will be the anticipated path required to implement the changes into the fleet and automated decision processes (substitution algorithm) currently employed. The paper will also present the most recent technologies identified for approval or additional testing and analysis including: supercritical CO{sub 2} cleaning, high pressure blasting (H{sub 2}O + baking soda), aqueous and semi-aqueous cleaning materials and processes, solvent replacements and dedicated parts washing systems with internal filtering capabilities, automated software for solvent/cleaning process substitute selection. Along with these technological advances, data availability (from on-line databases and CDROM Database libraries) will be identified and discussed.

  5. Materials Sciences Programs. Fiscal Year 1985

    International Nuclear Information System (INIS)

    1985-09-01

    The purpose of this report is to provide a convenient compilation and index of the DOE Materials Sciences Division programs. This compilation is primarily intended for use by administrators, managers, and scientists to help coordinate research. The report is divided into six sections. Section A contains all Laboratory projects, Section B has all contract research projects, Section C has projects funded under the Small Business Innovation Research Program, Sections D and E have information on DOE collaborative research centers, Section F gives distribution of funding, and Section G has various indexes

  6. Materials Sciences programs. Fiscal year 1982

    International Nuclear Information System (INIS)

    1982-09-01

    The purpose of this report is to provide a convenient compilation and index of the DOE Materials Sciences Division programs. This compilation is intended for use by administrators, managers, and scientists to help coordinate research and as an aid in selecting new programs. The report is divided into five sections. Section A contains all laboratory projects, Section B has all contract research projects, Section C has information on DOE collaborative research centers, Section D shows distribution of funding, and Section E has various indices

  7. Abstraction Mechanisms in the BETA Programming Language

    DEFF Research Database (Denmark)

    Kristensen, Bent Bruun; Madsen, Ole Lehrmann; Møller-Pedersen, Birger

    1983-01-01

    . It is then necessary that the abstraction mechanisms are powerful in order to define more specialized constructs. BETA is an object oriented language like SIMULA 67 ([SIMULA]) and SMALLTALK ([SMALLTALK]). By this is meant that a construct like the SIMULA class/subclass mechanism is fundamental in BETA. In contrast......]) --- covering both data, procedural and control abstractions, substituting constructs like class, procedure, function and type. Correspondingly objects, procedure activation records and variables are all regarded as special cases of the basic building block of program executions: the entity. A pattern thus......The BETA programming language is developed as part of the BETA project. The purpose of this project is to develop concepts, constructs and tools in the field of programming and programming languages. BETA has been developed from 1975 on and the various stages of the language are documented in [BETA...

  8. Mechanics in Composite Materials and Process

    International Nuclear Information System (INIS)

    Lee, Dae Gil

    1993-03-01

    This book includes introduction of composite materials, stress, in-plane stiffness of laminates strain rate, ply stress, failure criterion and bending, composite materials micromechanics, composite plates and micromechanics of composite materials. It also deals with process of composite materials such as autoclave vacuum bag degassing process, connection of composite materials, filament winding process, resin transfer molding, sheet molding compound and compression molding.

  9. Thermal hydraulics and mechanics core design programs

    International Nuclear Information System (INIS)

    Heinecke, J.

    1992-10-01

    The report documents the work performed within the Research and Development Task T hermal hydraulics and mechanics core design programs , funded by the German government. It contains the development of new codes, the extension of existing codes, the qualification and verification of codes and the development of a code library. The overall goal of this work was to adapt the system of thermal hydraulics and mechanics codes to the permanently growing requirements of the status of science and technology

  10. Fusion reactor materials program plan. Section III. Plasma material interaction

    International Nuclear Information System (INIS)

    1978-07-01

    A discussion of materials-related problems and an analysis of such problems is given for each major topical area. The strategy that will be used to solve the materials problems is described. As part of this program strategy, a series of major milestones is identified that extends over the next 20 years. Detailed task descriptions for the next five years leading to the achievement of the major milestones are given. Each task is described on a separate page (or task sheet) which includes the task number, task title, objective, scope, and the major milestones addressed by the task. Secondary milestones within a given task or subtask are defined, together with a priority assignment and an estimate of man-years to accomplish the work. Each Plan is organized along major topics which parallel the Subtask organization of the Task Group responsible for the Plan

  11. Borehole Plugging-Materials Development Program

    International Nuclear Information System (INIS)

    Gulick, C.W. Jr.

    1978-06-01

    This report discusses the background and first year's results of the grouting materials development program for plugging boreholes associated with the Nuclear Waste Isolation Pilot Plant. The grouts are to be pumpable, impermeable, and durable for many thousands of years. The work was done at the Concrete Laboratory of the U.S. Army Engineer Waterways Experiment Station (WES), Vicksburg, Mississippi. The workability, strength, porosity, bonding, expansion, and permeability data are summarized and discussed. The work is continuing at WES

  12. Ukrainian Program for Material Science in Microgravity

    Science.gov (United States)

    Fedorov, Oleg

    Ukrainian Program for Material Sciences in Microgravity O.P. Fedorov, Space Research Insti-tute of NASU -NSAU, Kyiv, The aim of the report is to present previous and current approach of Ukrainian research society to the prospect of material sciences in microgravity. This approach is based on analysis of Ukrainian program of research in microgravity, preparation of Russian -Ukrainian experiments on Russian segment of ISS and development of new Ukrainian strategy of space activity for the years 2010-2030. Two parts of issues are discussed: (i) the evolution of our views on the priorities in microgravity research (ii) current experiments under preparation and important ground-based results. item1 The concept of "space industrialization" and relevant efforts in Soviet and post -Soviet Ukrainian research institutions are reviewed. The main topics are: melt supercooling, crystal growing, testing of materials, electric welding and study of near-Earth environment. The anticipated and current results are compared. item 2. The main experiments in the framework of Ukrainian-Russian Research Program for Russian Segment of ISS are reviewed. Flight installations under development and ground-based results of the experiments on directional solidification, heat pipes, tribological testing, biocorrosion study is presented. Ground-based experiments and theoretical study of directional solidification of transparent alloys are reviewed as well as preparation of MORPHOS installation for study of succinonitrile -acetone in microgravity.

  13. Programs of the Materials and Radiation Effects Branch

    International Nuclear Information System (INIS)

    Dalder, E.N.C.

    1976-01-01

    This report describes specific efforts devoted to resolving fusion reactor materials needs as they relate to major fusion power program objectives and construction of major fusion facilities. Summaries of ERDA-sponsored research being conducted on the following areas are given: surface program, bulk irradiation program, dosimetry program, materials selection and development program, and neutron source development program

  14. Advanced gas cooled nuclear reactor materials evaluation and development program

    International Nuclear Information System (INIS)

    1977-01-01

    Results of work performed from January 1, 1977 through March 31, 1977 on the Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program are presented. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Process Heat and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (impure Helium), high temperatures, and long time exposures, on the mechanical properties and structural and surface stability of selected candidate alloys. A second objective is to select and recommend materials for future test facilities and more extensive qualification programs. Work covered in this report includes progress to date on alloy selection for VHTR Nuclear Process Heat (NPH) applications and for DCHT applications. The present status on the simulated reactor helium loop design and on designs for the testing and analysis facilities and equipment is discussed

  15. Materials surveillance program for C-E NSSS reactor vessels

    International Nuclear Information System (INIS)

    Koziol, J.J.

    1977-01-01

    Irradiation surveillance programs for light water NSSS reactor vessels provide the means by which the utility can assess the extent of neutron-induced changes in the reactor vessel materials. These programs are conducted to verify, by direct measurement, the conservatism in the predicted radiation-induced changes and hence the operational parameters (i.e., heat-up, cooldown, and pressurization rates). In addition, such programs provide assurance that the scheduled adjustments in the operational parameters are made with ample margin for safe operation of the plant. During the past 3 years, several documents have been promulgated establishing the criteria for determining both the initial properties of the reactor vessel materials as well as measurement of changes in these initial properties as a result of irradiation. These documents, ASTM E-185-73, ''Recommended Practice for Surveillance Tests for Nuclear Reactor Vessels,'' and Appendix H to 10 CFR 50, ''Reactor Vessel Material Surveillance Program Requirements,'' are complementary to each other. They are the result of a change in the basic philosophy regarding the design and analysis of reactor vessels. In effect, the empirical ''transition temperature approach,'' which was used for design, was replaced by the ''analytical fracture mechanics approach.'' The implementation of this technique was described in Welding Research Council Bulletin 1975 and Appendix G to ASME Code Section III. Further definition of requirements appears in Appendix G to 10 CFR 50 published in July 1973. It is the intent of this paper to describe (1) a typical materials surveillance program for the reactor vessel of a Combustion Engineering NSSS, and (2) how the results of such programs, as well as experimental programs provide feed-back for improvement of materials to enhance their radiation resistance and thereby further improve the safety and reliability of future plants. (author)

  16. Mechanical and materials engineering of modern structure and component design

    CERN Document Server

    Altenbach, Holm

    2015-01-01

    This book presents the latest findings on mechanical and materials engineering as applied to the design of modern engineering materials and components. The contributions cover the classical fields of mechanical, civil and materials engineering, as well as bioengineering and advanced materials processing and optimization. The materials and structures discussed can be categorized into modern steels, aluminium and titanium alloys, polymers/composite materials, biological and natural materials, material hybrids and modern nano-based materials. Analytical modelling, numerical simulation, state-of-the-art design tools and advanced experimental techniques are applied to characterize the materials’ performance and to design and optimize structures in different fields of engineering applications.

  17. Mechanically programmed shape change in laminated elastomeric composites.

    Science.gov (United States)

    Robertson, Jaimee M; Torbati, Amir H; Rodriguez, Erika D; Mao, Yiqi; Baker, Richard M; Qi, H Jerry; Mather, Patrick T

    2015-07-28

    Soft, anisotropic materials, such as myocardium in the heart and the extracellular matrix surrounding cells, are commonly found in nature. This anisotropy leads to specialized responses and is imperative to material functionality, yet few soft materials exhibiting similar anisotropy have been developed. Our group introduced an anisotropic shape memory elastomeric composite (A-SMEC) composed of non-woven, aligned polymer fibers embedded in an elastomeric matrix. The composite exhibited shape memory (SM) behavior with significant anisotropy in room-temperature shape fixing. Here, we exploit this anisotropy by bonding together laminates with oblique anisotropy such that tensile deformation at room temperature - mechanical programming - results in coiling. This response is a breakthrough in mechanical programming, since non-affine shape change is achieved by simply stretching the layered A-SMECs at room temperature. We will show that pitch and curvature of curled geometries depend on fiber orientations and the degree of strain programmed into the material. To validate experimental results, a model was developed that captures the viscoplastic response of A-SMECs. Theoretical results correlated well with experimental data, supporting our conclusions and ensuring attainability of predictable curling geometries. We envision these smart, soft, shape changing materials will have aerospace and medical applications.

  18. Advanced neutron source materials surveillance program

    International Nuclear Information System (INIS)

    Heavilin, S.M.

    1995-01-01

    The Advanced Neutron Source (ANS) will be composed of several different materials, one of which is 6061-T6 aluminum. Among other components, the reflector vessel and the core pressure boundary tube (CPBT), are to be made of 6061-T6 aluminum. These components will be subjected to high thermal neutron fluences and will require a surveillance program to monitor the strength and fracture toughness of the 6061-T6 aluminum over their lifetimes. The purpose of this paper is to explain the steps that were taken in the summer of 1994 toward developing the surveillance program. The first goal was to decide upon standard specimens to use in the fracture toughness and tensile testing. Second, facilities had to be chosen for specimens representing the CPBT and the reflector vessel base, weld, and heat-affected-zone (HAZ) metals. Third, a timetable had to be defined to determine when to remove the specimens for testing

  19. Mechanical Behavior of Advanced Aerospace Materials

    National Research Council Canada - National Science Library

    Ashbaugh, Noel

    1997-01-01

    .... For a gamma titanium aluminide alloy, the coarse and refined lamellar materials with colony sizes equal to 700 and 280 micrometers, respectively, have substantially greater crack growth resistance...

  20. On the Mechanical Behavior of Advanced Composite Material Structures

    Science.gov (United States)

    Vinson, Jack

    During the period between 1993 and 2004, the author, as well as some colleagues and graduate students, had the honor to be supported by the Office of Naval Research to conduct research in several aspects of the behavior of structures composed of composite materials. The topics involved in this research program were numerous, but all contributed to increasing the understanding of how various structures that are useful for marine applications behaved. More specifically, the research topics focused on the reaction of structures that were made of fiber reinforced polymer matrix composites when subjected to various loads and environmental conditions. This included the behavior of beam, plate/panel and shell structures. It involved studies that are applicable to fiberglass, graphite/carbon and Kevlar fibers imbedded in epoxy, polyester and other polymeric matrices. Unidirectional, cross-ply, angle ply, and woven composites were involved, both in laminated, monocoque as well as in sandwich constructions. Mid-plane symmetric as well as asymmetric laminates were studied, the latter involving bending-stretching coupling and other couplings that only can be achieved with advanced composite materials. The composite structures studied involved static loads, dynamic loading, shock loading as well as thermal and hygrothermal environments. One major consideration was determining the mechanical properties of composite materials subjected to high strain rates because the mechanical properties vary so significantly as the strain rate increases. A considerable number of references are cited for further reading and study for those interested.

  1. Strategy for future laboratory rock mechanics programs

    International Nuclear Information System (INIS)

    Butcher, B.M.; Jones, A.K.

    1985-01-01

    A strategy for future experimental rock mechanics laboratory programs at Sandia National Laboratories is described. This strategy is motivated by the need for long range planning of rock mechanics programs addressing the stability of complex underground structures, changes in in situ stress states during resource recovery and underground explosion technology. It is based on: (1) recent advances in underground structure stability analysis which make three-dimensional calculations feasible, and (2) new developments in load path control of laboratory stress-strain tests which permit duplication of stress and strain histories in critical parts of a structure, as determined by numerical analysis. The major constraint in the strategy is the assumption that there are no in situ joint features or sample size effects which might prevent simulation of in situ response in the laboratory. 3 refs., 5 figs

  2. Programmed necrosis and necroptosis – molecular mechanisms

    Directory of Open Access Journals (Sweden)

    Agata Giżycka

    2015-12-01

    Full Text Available Programmed necrosis has been proven vital for organism development and homeostasis maintenance. Its regulatory effects on functional activity of the immune system, as well as on pathways regulating the death mechanisms in cells with diminished apoptotic activity, including malignant cells, have been confirmed. There is also increasing evidence indicating necrosis involvement in many human pathologies. Contrary to previous beliefs, necrosis is not only a passive, pathological, gene-independent process. However, the current knowledge regarding molecular regulation of programmed necrosis is scarce. In part this is due to the multiplicity and complexity of signaling pathways involved in programmed necrosis, as well as the absence of specific cellular markers identifying this process, but also the ambiguous and imprecise international terminology. This review presents the current state of the art on molecular mechanisms of programmed necrosis. In particular, its specific and frequent form, necroptosis, is discussed. The role of RIP1 and RIP3 kinases in this process is presented, as well as the diverse pathways induced by ligation of tumor necrosis factor α, to its receptor, TNFR1, i.e. cell survival, apoptosis or necroptosis.

  3. U.S. fast reactor materials and structures program

    International Nuclear Information System (INIS)

    Harms, W.O.; Purdy, C.M.

    1984-01-01

    The U.S. DOE has sponsored a vigorous breeder reactor materials and structures program for 15 years. Important contributions have resulted from this effort in the areas of design (inelastic rules, verified methods, seismic criteria, mechanical properties data); resolution of licensing issues (technical witnessing, confirmatory testing); construction (fabrication/welding procedures, nondestructive testing techniques); and operation (sodium purification, instrumentation and chemical analysis, radioactivity control, and in-service inspection. The national LMFBR program currently is being restructured. The Materials and Structures Program will focus its efforts in the following areas: (1) removal of anticipated licensing impediments through confirmation of the adequacy of structural design methods and criteria for components containing welds and geometric discontinuities, the generation of mechanical properties for stainless steel castings and weldments, and the evaluation of irradiation effects; (2) qualification of modified 9 Cr-1 Mo steel and tribological coatings for design flexibility; (3) development of improved inelastic design guidelines and procedures; (4) reform of design codes and standards and engineering practices, leading to simpler, less conservative rules and to simplified design analysis methods; and (5) incorporation of information from foreign program

  4. Improvement of the Material's Mechanical Characteristics using ...

    African Journals Online (AJOL)

    pc

    2018-03-05

    Mar 5, 2018 ... to Hardening Process Control (HPC) in order to improvement of the material's ... particular circumstances of the models characteristics used and the exact definition ..... In the case of simulation and testing in Matlab of the HFC.

  5. Coordination Between the HEU Transparency Program and the Material Protection, Control and Accountability Program

    International Nuclear Information System (INIS)

    Glaser, J.; Hernandez, J.; Dougherty, D.; Bieniawski, A.; Cahalane, P.; Mastal, E.

    2000-01-01

    DOE sponsored programs such as Material Protection Control and Accountability (MPC and A) and implementation of the Highly-Enriched Uranium (HEU) Transparency Program send US personnel into Russian nuclear facilities and receive Russian representatives from these programs. While there is overlap in the Russian nuclear facilities visited by these two programs, there had not been any formal mechanism to share information between them. Recently, an MPC and A/HEU Working Group was developed to facilitate the sharing of appropriate information and to address concerns expressed by Minatom and Russian facility personnel such as US visit scheduling conflicts. This paper discusses the goals of the Working Group and ways it has helped to allow the programs to work more efficiently with the Russian facilities

  6. Sandia National Laboratories, California Hazardous Materials Management Program annual report.

    Energy Technology Data Exchange (ETDEWEB)

    Brynildson, Mark E.

    2011-02-01

    The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Hazardous Materials Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. This program annual report describes the activities undertaken during the calender past year, and activities planned in future years to implement the Hazardous Materials Management Program, one of six programs that supports environmental management at SNL/CA.

  7. Mechanics of composite material subjected to eigenstress

    DEFF Research Database (Denmark)

    Fuglsang Nielsen, L.

    In this SBI Bulletin a theory is presented dealing with the mechanical behavior of composites subjected to hygro-thermal actions such as shrinkage caused by moisture variations and expansion caused by temperature variations of freezing of water in pore systems. Special attention is given to the t......In this SBI Bulletin a theory is presented dealing with the mechanical behavior of composites subjected to hygro-thermal actions such as shrinkage caused by moisture variations and expansion caused by temperature variations of freezing of water in pore systems. Special attention is given...

  8. Mechanisms of Fetal Programming in Hypertension

    Directory of Open Access Journals (Sweden)

    John Edward Jones

    2012-01-01

    Full Text Available Events that occur in the early fetal environment have been linked to long-term health and lifespan consequences in the adult. Intrauterine growth restriction (IUGR, which may occur as a result of nutrient insufficiency, exposure to hormones, or disruptions in placental structure or function, may induce the fetus to alter its developmental program in order to adapt to the new conditions. IUGR may result in a decrease in the expression of genes that are responsible for nephrogenesis as nutrients are rerouted to the development of more essential organs. Fetal survival under these conditions often results in low birth weight and a deficit in nephron endowment, which are associated with hypertension in adults. Interestingly, male IUGR offspring appear to be more severely affected than females, suggesting that sex hormones may be involved. The processes of fetal programming of hypertension are complex, and we are only beginning to understand the underlying mechanisms.

  9. Material, compressional and mechanical properties of Borassus ...

    African Journals Online (AJOL)

    The compressional and mechanical properties of tablet formulations incorporating native and modified Borassus aethiopum starches as binder were evaluated. The native Borassus aethiopum starch (BAS) was modified to yield fully gelatinised starch (FGBAS) and microcrystalline starch (MBAS). The compressional ...

  10. Competency-Based Materials for the Florida Automotive Mechanics Curriculum

    Science.gov (United States)

    Goodson, Ludy; And Others

    1978-01-01

    Describes Florida's new automotive mechanics curriculum, an individualized, self-paced learning sequence that combines text material, review exercises and actual work activities. Development of the materials, including incorporation of Florida's V-TECS catalog of performance objectives in auto mechanics, is described. A field-test experience of a…

  11. Physics and Mechanics of New Materials and Their Applications

    CERN Document Server

    Chang, Shun-Hsyung; Gupta, Vijay

    2018-01-01

    This book presents selected peer-reviewed contributions from the 2017 International Conference on “Physics and Mechanics of New Materials and Their Applications”, PHENMA 2017 (Jabalpur, India, 14–16 October, 2017), which is devoted to processing techniques, physics, mechanics, and applications of advanced materials. The book focuses on a wide spectrum of nanostructures, ferroelectric crystals, materials and composites as well as promising materials with special properties. It presents nanotechnology approaches, modern environmentally friendly piezoelectric and ferromagnetic techniques and physical and mechanical studies of the structural and physical–mechanical properties of materials. Various original mathematical and numerical methods are applied to the solution of different technological, mechanical and physical problems that are interesting from theoretical, modeling and experimental points of view. Further, the book highlights novel devices with high accuracy, longevity and extended capabilities ...

  12. 7 CFR 3406.12 - Program application materials-teaching.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Program application materials-teaching. 3406.12... GRANTS PROGRAM Preparation of a Teaching Proposal § 3406.12 Program application materials—teaching... program, and the forms needed to prepare and submit teaching grant applications under the program. ...

  13. Mechanical characterization of materials for dental applications

    International Nuclear Information System (INIS)

    Pajares, A.; Miranda, P.; Guiberteau, F.; Cumbrera, F. I.

    2001-01-01

    An study of the damage induced in dental materials and model multilayer systems by masticatory contact stresses, simulated by hertz ian indentation test, have been performed. In particular, the nature of induced damage has been identified, and quantified from stress-strain curves and critical loads for yielding or crack initiation. For multilayer systems, test have been numerically simulated using finite element techniques (FEM). FEM simulations complement indentation test, allowing to justify the observed fracture modes from calculated stress fields. Practical implications can be derived from our results, relevant to the design of multilayer structures tolerant to contact damage. (Author) 34 refs

  14. Mechanical Components from Highly Recoverable, Low Apparent Modulus Materials

    Science.gov (United States)

    Padula, Santo, II (Inventor); Noebe, Ronald D. (Inventor); Stanford, Malcolm K. (Inventor); DellaCorte, Christopher (Inventor)

    2015-01-01

    A material for use as a mechanical component is formed of a superelastic intermetallic material having a low apparent modulus and a high hardness. The superelastic intermetallic material is conditioned to be dimensionally stable, devoid of any shape memory effect and have a stable superelastic response without irrecoverable deformation while exhibiting strains of at least 3%. The method of conditioning the superelastic intermetallic material is described. Another embodiment relates to lightweight materials known as ordered intermetallics that perform well in sliding wear applications using conventional liquid lubricants and are therefore suitable for resilient, high performance mechanical components such as gears and bearings.

  15. Mechanical compatibility and stress analyses in composite materials

    International Nuclear Information System (INIS)

    Schimmoeller, H.; Ruge, J.

    1976-01-01

    This paper gives a short description of the problem of mechanical interactions and mechanical compatibility in composite bodies. The formation of stress-strain states, caused by the mechanical compatibility by bonding of the interfaces, is discussed. The difference between the continuous and discontinuous type of material transition in the interface is described. Flat laminated materials are at first considered. For this type of composite bodies thermal stresses and thermal residual stresses are elastically-plastically calculated. (orig.) [de

  16. Development of LTCC Materials with High Mechanical Strength

    International Nuclear Information System (INIS)

    Kawai, Shinya; Nishiura, Sousuke; Terashi, Yoshitake; Furuse, Tatsuji

    2011-01-01

    We have developed LTCC materials suitable for substrates of RF modules used in mobile phone. LTCC can provide excellent solutions to requirements of RF modules, such as down-sizing, embedded elements and high performance. It is also important that LTCC material has high mechanical strength to reduce risk of fracture by mechanical impact. We have established a method of material design for high mechanical strength. There are two successive steps in the concept to achieve high mechanical strength. The first step is to improve mechanical strength by increasing the Young's modulus, and the second step is either further improvement through the Young's modulus or enhancement of the fracture energy. The developed material, so called high-strength LTCC, thus possesses mechanical strength of 400MPa, which is twice as strong as conventional material whose mechanical strength is approximately 200MPa in typical. As a result, high-strength LTCC shows an excellent mechanical reliability, against the drop impact test for example. The paper presents material design and properties of LTCC materials.

  17. Basic Gasoline Engine Mechanics. Florida Vocational Program Guide.

    Science.gov (United States)

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This packet contains a program guide and Career Merit Achievement Plan (Career MAP) for the implementation of a basic gasoline engine mechanics program in Florida secondary and postsecondary schools. The program guide describes the program content and structure, provides a program description, lists job titles under the program, and includes a…

  18. Neutron irradiation experiments for fusion reactor materials through JUPITER program

    International Nuclear Information System (INIS)

    Abe, K.; Namba, C.; Wiffen, F.W.; Jones, R.H.

    1998-01-01

    A Japan-USA program of irradiation experiments for fusion research, ''JUPITER'', has been established as a 6 year program from 1995 to 2000. The goal is to study ''the dynamic behavior of fusion reactor materials and their response to variable and complex irradiation environment''. This is phase-three of the collaborative program, which follows RTNS-II program (phase-1: 1982-1986) and FFTF/MOTA program (phase-2: 1987-1994). This program is to provide a scientific basis for application of materials performance data, generated by fission reactor experiments, to anticipated fusion environments. Following the systematic study on cumulative irradiation effects, done through FFTF/MOTA program. JUPITER is emphasizing the importance of dynamic irradiation effects on materials performance in fusion systems. The irradiation experiments in this program include low activation structural materials, functional ceramics and other innovative materials. The experimental data are analyzed by theoretical modeling and computer simulation to integrate the above effects. (orig.)

  19. Microfabrication of hierarchical structures for engineered mechanical materials

    Science.gov (United States)

    Vera Canudas, Marc

    Materials found in nature present, in some cases, unique properties from their constituents that are of great interest in engineered materials for applications ranging from structural materials for the construction of bridges, canals and buildings to the fabrication of new lightweight composites for airplane and automotive bodies, to protective thin film coatings, amongst other fields. Research in the growing field of biomimetic materials indicates that the micro-architectures present in natural materials are critical to their macroscopic mechanical properties. A better understanding of the effect that structure and hierarchy across scales have on the material properties will enable engineered materials with enhanced properties. At the moment, very few theoretical models predict mechanical properties of simple materials based on their microstructures. Moreover these models are based on observations from complex biological systems. One way to overcome this challenge is through the use of microfabrication techniques to design and fabricate simple materials, more appropriate for the study of hierarchical organizations and microstructured materials. Arrays of structures with controlled geometry and dimension can be designed and fabricated at different length scales, ranging from a few hundred nanometers to centimeters, in order to mimic similar systems found in nature. In this thesis, materials have been fabricated in order to gain fundamental insight into the complex hierarchical materials found in nature and to engineer novel materials with enhanced mechanical properties. The materials fabricated here were mechanically characterized and compared to simple mechanics models to describe their behavior with the goal of applying the knowledge acquired to the design and synthesis of future engineered materials with novel properties.

  20. Edge orientations of mechanically exfoliated anisotropic two-dimensional materials

    Science.gov (United States)

    Yang, Juntan; Wang, Yi; Li, Yinfeng; Gao, Huajian; Chai, Yang; Yao, Haimin

    2018-03-01

    Mechanical exfoliation is an approach widely applied to prepare high-quality two-dimensional (2D) materials for investigating their intrinsic physical properties. During mechanical exfoliation, in-plane cleavage results in new edges whose orientations play an important role in determining the properties of the as-exfoliated 2D materials especially those with high anisotropy. Here, we systematically investigate the factors affecting the edge orientation of 2D materials obtained by mechanical exfoliation. Our theoretical study manifests that the fractured direction during mechanical exfoliation is determined synergistically by the tearing direction and material anisotropy of fracture energy. For a specific 2D material, our theory enables us to predict the possible edge orientations of the exfoliated flakes as well as their occurring probabilities. The theoretical prediction is experimentally verified by examining the inter-edge angles of the exfoliated flakes of four typical 2D materials including graphene, MoS2, PtS2, and black phosphorus. This work not only sheds light on the mechanics of exfoliation of the 2D materials but also provides a new approach to deriving information of edge orientations of mechanically exfoliated 2D materials by data mining of their macroscopic geometric features.

  1. Space radiation interaction mechanisms in materials

    International Nuclear Information System (INIS)

    Wilson, J.W.

    1983-01-01

    Models of charged-particle impact under conditions typical of the space environment are reported, with a focus on impact excitation and nuclear reactions, especially for heavy ions. Impact excitation is studied by using a global model for electronic excitation based on formal relations through the classical dielectric function to derive an approximation related to the local plasma (electron density distribution) within the atoms and molecules and corrections to the model resulting from the nonfluid nature of this plasma are discussed. Nuclear reactions are studied by reducing quantum-mechanical treatment of this general N-body problem to an equivalent two-body problem that is solvable, and by comparing the results with experimental data. The equations for heavy-charged-particle transport are derived and solution techniques demonstrated. Finally, these methods of analysis are applied to study the change in the electrical properties of a GaAs semiconductor for photovoltaic applications. Proton damage to GaAs crystals is found to arise from stable replacement defects and to be nonannealable, in contrast to electron-induced damage. 17 references

  2. Bio-mimetic mechanisms of natural hierarchical materials: a review.

    Science.gov (United States)

    Chen, Qiang; Pugno, Nicola M

    2013-03-01

    Natural selection and evolution develop a huge amount of biological materials in different environments (e.g. lotus in water and opuntia in desert). These biological materials possess many inspiring properties, which hint scientists and engineers to find some useful clues to create new materials or update the existing ones. In this review, we highlight some well-studied (e.g. nacre shell) and newly-studied (e.g. turtle shell) natural materials, and summarize their hierarchical structures and mechanisms behind their mechanical properties, from animals to plants. These fascinating mechanisms suggest to researchers to investigate natural materials deeply and broadly, and to design or fabricate new bio-inspired materials to serve our life. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Material recognition based on thermal cues: Mechanisms and applications.

    Science.gov (United States)

    Ho, Hsin-Ni

    2018-01-01

    Some materials feel colder to the touch than others, and we can use this difference in perceived coldness for material recognition. This review focuses on the mechanisms underlying material recognition based on thermal cues. It provides an overview of the physical, perceptual, and cognitive processes involved in material recognition. It also describes engineering domains in which material recognition based on thermal cues have been applied. This includes haptic interfaces that seek to reproduce the sensations associated with contact in virtual environments and tactile sensors aim for automatic material recognition. The review concludes by considering the contributions of this line of research in both science and engineering.

  4. Multiscale experimental mechanics of hierarchical carbon-based materials.

    Science.gov (United States)

    Espinosa, Horacio D; Filleter, Tobin; Naraghi, Mohammad

    2012-06-05

    Investigation of the mechanics of natural materials, such as spider silk, abalone shells, and bone, has provided great insight into the design of materials that can simultaneously achieve high specific strength and toughness. Research has shown that their emergent mechanical properties are owed in part to their specific self-organization in hierarchical molecular structures, from nanoscale to macroscale, as well as their mixing and bonding. To apply these findings to manmade materials, researchers have devoted significant efforts in developing a fundamental understanding of multiscale mechanics of materials and its application to the design of novel materials with superior mechanical performance. These efforts included the utilization of some of the most promising carbon-based nanomaterials, such as carbon nanotubes, carbon nanofibers, and graphene, together with a variety of matrix materials. At the core of these efforts lies the need to characterize material mechanical behavior across multiple length scales starting from nanoscale characterization of constituents and their interactions to emerging micro- and macroscale properties. In this report, progress made in experimental tools and methods currently used for material characterization across multiple length scales is reviewed, as well as a discussion of how they have impacted our current understanding of the mechanics of hierarchical carbon-based materials. In addition, insight is provided into strategies for bridging experiments across length scales, which are essential in establishing a multiscale characterization approach. While the focus of this progress report is in experimental methods, their concerted use with theoretical-computational approaches towards the establishment of a robust material by design methodology is also discussed, which can pave the way for the development of novel materials possessing unprecedented mechanical properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Fetal programming of schizophrenia: select mechanisms.

    Science.gov (United States)

    Debnath, Monojit; Venkatasubramanian, Ganesan; Berk, Michael

    2015-02-01

    Mounting evidence indicates that schizophrenia is associated with adverse intrauterine experiences. An adverse or suboptimal fetal environment can cause irreversible changes in brain that can subsequently exert long-lasting effects through resetting a diverse array of biological systems including endocrine, immune and nervous. It is evident from animal and imaging studies that subtle variations in the intrauterine environment can cause recognizable differences in brain structure and cognitive functions in the offspring. A wide variety of environmental factors may play a role in precipitating the emergent developmental dysregulation and the consequent evolution of psychiatric traits in early adulthood by inducing inflammatory, oxidative and nitrosative stress (IO&NS) pathways, mitochondrial dysfunction, apoptosis, and epigenetic dysregulation. However, the precise mechanisms behind such relationships and the specificity of the risk factors for schizophrenia remain exploratory. Considering the paucity of knowledge on fetal programming of schizophrenia, it is timely to consolidate the recent advances in the field and put forward an integrated overview of the mechanisms associated with fetal origin of schizophrenia. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Opportunities for the LWR ATF materials development program to contribute to the LBE-cooled ADS materials qualification program

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xing, E-mail: gongxingzfl@hotmail.com [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Li, Rui, E-mail: li-rui@cgnpc.com.cn [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Sun, Maozhou; Ren, Qisen [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Liu, Tong, E-mail: liutong@cgnpc.com.cn [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Short, Michael P., E-mail: hereiam@mit.edu [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, 02139 (United States)

    2016-12-15

    Accelerator-driven systems (ADS) are a promising approach for nuclear waste disposal. Nevertheless, the principal candidate materials proposed for ADS construction, such as the ferritic/martensitic steel, T91, and austenitic stainless steels, 316L and 15-15Ti, are not fully compatible with the liquid lead-bismuth eutectic (LBE) coolant. Under some operating conditions, liquid metal embrittlement (LME) or liquid metal corrosion (LMC) may occur in these steels when exposed to LBE. These environmentally-induced material degradation effects pose a threat to ADS reactor safety, as failure of the materials could initiate a severe accident, in which fission products are released into the coolant. Meanwhile, parallel efforts to develop accident-tolerant fuels (ATF) in light water reactors (LWRs) could provide both general materials design philosophies and specific material solutions to the ADS program. In this paper, the potential contributions of the ATF materials development program to the ADS materials qualification program are evaluated and discussed in terms of service conditions and materials performance requirements. Several specific areas where coordinated development may benefit both programs, including composite materials and selected coatings, are discussed. - Highlights: • ATF materials developed for LWRs could be candidate materials for the LBE-cooled ADS program. • Similar material design and protection philosophies are utilized in both programs. • Unique challenges of LBE-cooled ADS systems could possibly be addressed by LWR ATF materials. • More coordinated testing should be performed between the ATF and ADS programs.

  7. Advanced Industrial Materials Program. Annual progress report, FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    Stooksbury, F. [comp.

    1994-06-01

    Mission of the AIM program is to commercialize new/improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. Program investigators in the DOE national laboratories are working with about 100 companies, including 15 partners in CRDAs. Work is being done on intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The program supports other efforts in the Office of Industrial Technologies to assist the energy-consuming process industries. The aim of the AIM program is to bring materials from basic research to industrial application to strengthen the competitive position of US industry and save energy.

  8. Mechanics of advanced materials analysis of properties and performance

    CERN Document Server

    Matveenko, Valery

    2015-01-01

    The last decades have seen a large extension of types of materials employed in various applications. In many cases these materials demonstrate mechanical properties and performance that vary significantly from those of their traditional counterparts. Such uniqueness is sought – or even specially manufactured – to meet increased requirements on modern components and structures related to their specific use. As a result, mechanical behaviors of these materials under different loading and environmental conditions are outside the boundaries of traditional mechanics of materials, presupposing development of new characterization techniques, theoretical descriptions and numerical tools. The book presents interesting examples of recent developments in this area. Among the studied materials are bulk metallic glasses, metamaterials, special composites, piezoelectric smart structures, nonwovens, etc.

  9. U.S.-origin nuclear material removal program

    Energy Technology Data Exchange (ETDEWEB)

    Messick, C.E.; Galan, J.J. [U.S. Department of Energy, Washington, DC (United States). U.S.-Origin Nuclear Material Removal Program

    2014-12-15

    The United States (U.S.) Department of Energy (DOE) Global Threat Reduction Initiative's (GTRI) U.S.-Origin Nuclear Material Removal program, also known as the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program (FRR SNF AP), was established by the U.S. Department of Energy in May 1996. The program's mission provides a disposition pathway for certain U.S. origin spent nuclear fuel and other weapons-grade nuclear material. The program will continue until May 2016 with an additional three year window for fuel cooldown and transportation. This paper provides an update on recent program accomplishments, current program initiatives and future activities.

  10. U.S.-origin nuclear material removal program

    International Nuclear Information System (INIS)

    Messick, C.E.; Galan, J.J.

    2014-01-01

    The United States (U.S.) Department of Energy (DOE) Global Threat Reduction Initiative's (GTRI) U.S.-Origin Nuclear Material Removal program, also known as the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program (FRR SNF AP), was established by the U.S. Department of Energy in May 1996. The program's mission provides a disposition pathway for certain U.S. origin spent nuclear fuel and other weapons-grade nuclear material. The program will continue until May 2016 with an additional three year window for fuel cooldown and transportation. This paper provides an update on recent program accomplishments, current program initiatives and future activities.

  11. Size effects in the mechanical behavior of cellular materials

    NARCIS (Netherlands)

    Tekoglu, C; Onck, PR

    Effective mechanical properties of cellular materials depend strongly on the specimen size to the cell size ratio. Experimental studies performed on aluminium foams show that under uniaxial compression, the stiffness of these materials falls below the corresponding bulk value, when the ratio of the

  12. Fracture mechanics applied to the machining of brittle materials

    Energy Technology Data Exchange (ETDEWEB)

    Hiatt, G.D.; Strenkowski, J.S.

    1988-12-01

    Research has begun on incorporating fracture mechanics into a model of the orthogonal cutting of brittle materials. Residual stresses are calculated for the machined material by a combination of Eulerian and Lagrangian finite element models and then used in the calculation of stress intensity factors by the Green`s Function Method.

  13. Dynamic compressive mechanical response of a soft polymer material

    NARCIS (Netherlands)

    Fan, J.T.; Weerheijm, J.; Sluys, L.J.

    2015-01-01

    The dynamic mechanical behaviour of a soft polymer material (Clear Flex 75) was studied using a split Hopkinson pressure bar (SHPB) apparatus. Mechanical properties have been determined at moderate to high strain rates. Real time deformation and fracture were recorded using a high-speed camera.

  14. Stretchable polyurethane sponge reinforced magnetorheological material with enhanced mechanical properties

    International Nuclear Information System (INIS)

    Ge, Lin; Xuan, Shouhu; Liao, Guojiang; Yin, Tiantian; Gong, Xinglong

    2015-01-01

    A stretchable magnetorheological material (SMRM) consisting of micro-meter carbonyl iron (CI) particles, low cross-linking polyurethane (PU) polymer and porous PU sponge has been developed. Due to the presence of the PU sponge, the high-performance MR material can be reversibly stretched or bent, just as MR elastomers. When the CI content increases to 80 wt%, the magnetic induced modulus of the MR material can reach as high as 7.34 MPa and the corresponding relative MR effect increases to 820%. A possible strengthening mechanism of the SMRM was proposed. The attractive mechanical properties make the SMRM a promising candidate for future high-performance devices. (technical note)

  15. Program in change: shipment of hazardous materials at the INEL

    International Nuclear Information System (INIS)

    Reed, L.L.

    1984-01-01

    Positive measures such as education, control, and auditing ability should be incorporated into each hazardous material shipping program to assure compliance with regulations and the safe movement of hazardous materials. This paper discusses these and other pertinent components of a shipping program. 3 references

  16. Methods for evaluation of mechanical stress condition of materials

    Directory of Open Access Journals (Sweden)

    Mirchev Yordan

    2018-01-01

    Full Text Available Primary attention is given to the following methods: method by drilling cylindrical holes (drill method and integrated ultrasonic method using volume (longitudinal and transverse, surface, and sub-surface waves. Drill method allows determination of residual mechanical stress in small depth of material surfaces, assessing type, size, and orientation of principal stresses. For the first time, parallel studies are carried out of mechanical stress in materials using the electroacoustic effect of volume, surface and sub-surface waves on the one hand, and effective mechanical stresses on the other. The experimental results present electroacoustic coefficients for different types of waves in the material of gas pipeline tube of 243 mm diameter and 14 mm thickness. These are used to evaluate mechanical stresses in pipelines, according to active GOST standards.

  17. Hazardous materials transportation and emergency response programs

    International Nuclear Information System (INIS)

    Joy, D.S.; Fore, C.S.

    1983-01-01

    This presentation consists of the following visual aids; (1) detailed routing capabilities of truck, rail, barge; (2) legislative data base for hazardous materials; and (3) emergency response of accident site Eddyville, Kentucky (airports in vicinity of Eddyville, KY)

  18. Numerical simulation of mechanical behavior of composite materials

    CERN Document Server

    Oller, Sergio

    2014-01-01

    An original mechanical formulation to treat nonlinear orthotropic behavior of composite materials is presented in this book. It also examines different formulations that allow us to evaluate the behavior of composite materials through the composition of its components, obtaining a new composite material. Also two multiple scale homogenization methods are given, one based on the analytical study of the cells (Ad-hoc homogenization), and other one, more general based on the finite element procedure applied on the macro scale (upper-scale) and in the micro scale (sub-scale). A very general formulation to simulate the mechanical behavior for traditional composite structures (plywood, reinforced concrete, masonry, etc.), as well as the new composite materials reinforced with long and short fibers, nanotubes, etc., are also shown in this work. Typical phenomena occurring in composite materials are also described in this work, including fiber-matrix debounding, local buckling of fibers and its coupling with the over...

  19. Mechanical Testing of Carbon Based Woven Thermal Protection Materials

    Science.gov (United States)

    Pham, John; Agrawal, Parul; Arnold, James O.; Peterson, Keith; Venkatapathy, Ethiraj

    2013-01-01

    Three Dimensional Woven thermal protection system (TPS) materials are one of the enabling technologies for mechanically deployable hypersonic decelerator systems. These materials have been shown capable of serving a dual purpose as TPS and as structural load bearing members during entry and descent operations. In order to ensure successful structural performance, it is important to characterize the mechanical properties of these materials prior to and post exposure to entry-like heating conditions. This research focuses on the changes in load bearing capacity of woven TPS materials after being subjected to arcjet simulations of entry heating. Preliminary testing of arcjet tested materials [1] has shown a mechanical degradation. However, their residual strength is significantly more than the requirements for a mission to Venus [2]. A systematic investigation at the macro and microstructural scales is reported here to explore the potential causes of this degradation. The effects of heating on the sizing (an epoxy resin coating used to reduce friction and wear during fiber handling) are discussed as one of the possible causes for the decrease in mechanical properties. This investigation also provides valuable guidelines for margin policies for future mechanically deployable entry systems.

  20. Effect of mechanical properties on erosion resistance of ductile materials

    Science.gov (United States)

    Levin, Boris Feliksovih

    Solid particle erosion (SPE) resistance of ductile Fe, Ni, and Co-based alloys as well as commercially pure Ni and Cu was studied. A model for SPE behavior of ductile materials is presented. The model incorporates the mechanical properties of the materials at the deformation conditions associated with SPE process, as well as the evolution of these properties during the erosion induced deformation. An erosion parameter was formulated based on consideration of the energy loss during erosion, and incorporates the material's hardness and toughness at high strain rates. The erosion model predicts that materials combining high hardness and toughness can exhibit good erosion resistance. To measure mechanical properties of materials, high strain rate compression tests using Hopkinson bar technique were conducted at strain rates similar to those during erosion. From these tests, failure strength and strain during erosion were estimated and used to calculate toughness of the materials. The proposed erosion parameter shows good correlation with experimentally measured erosion rates for all tested materials. To analyze subsurface deformation during erosion, microhardness and nanoindentation tests were performed on the cross-sections of the eroded materials and the size of the plastically deformed zone and the increase in materials hardness due to erosion were determined. A nanoindentation method was developed to estimate the restitution coefficient within plastically deformed regions of the eroded samples which provides a measure of the rebounding ability of a material during particle impact. An increase in hardness near the eroded surface led to an increase in restitution coefficient. Also, the stress rates imposed below the eroded surface were comparable to those measured during high strain-rate compression tests (10sp3-10sp4 ssp{-1}). A new parameter, "area under the microhardness curve" was developed that represents the ability of a material to absorb impact energy. By

  1. Adhesion mechanisms of nanoparticle silver to substrate materials: identification

    International Nuclear Information System (INIS)

    Joo, Sungchul; Baldwin, Daniel F

    2010-01-01

    Nanoparticle silver (NPS) conductors are increasingly being investigated for printed electronics applications. However, the adhesion mechanism of the nanoparticle silver to substrate materials has not been identified yet. In particular, the adhesion of NPS to organic materials such as the widely used polyimide Kapton HN and Kapton FPC dry films is concerned with low adhesion strength because the processed polymer surface is chemically inert. Moreover, its adhesion to substrate materials such as benzocyclobutene (BCB), copper and aluminum was found to be very weak. Therefore, in this paper, the mechanisms of NPS adhesion to organic and inorganic materials are identified as the first step in improving NPS adhesion strength. Improving the adhesion strength of NPS will be the key issue for printed electronics applications. The adhesion of NPS to substrate materials was found to be mainly attributed to van der Waals forces based on particle adhesion mechanisms. This finding provides the initiative of developing an adhesion prediction model of NPS to substrate materials in order to provide guidelines for improving the NPS adhesion strength to the substrate materials used in printed electronics.

  2. Mechanical behaviour of composite materials made by resin film infusion

    Directory of Open Access Journals (Sweden)

    Casavola C.

    2010-06-01

    Full Text Available Innovative composite materials are frequently used in designing aerospace, naval and automotive components. In the typical structure of composites, multiple layers are stacked together with a particular sequence in order to give specific mechanical properties. Layers are organized with different angles, different sequences and different technological process to obtain a new and innovative material. From the standpoint of engineering designer it is useful to consider the single layer of composite as macroscopically homogeneous material. However, composites are non homogeneous bodies. Moreover, layers are not often perfectly bonded together and delamination often occurs. Other violations of lamination theory hypotheses, such as plane stress and thin material, are not unusual and in many cases the transverse shear flexibility and the thickness-normal stiffness should be considered. Therefore the real behaviour of composite materials is quite different from the predictions coming from the traditional lamination theory. Due to the increasing structural performance required to innovative composites, the knowledge of the mechanical properties for different loading cases is a fundamental source of concern. Experimental characterization of materials and structures in different environmental conditions is extremely important to understand the mechanical behaviour of these new materials. The purpose of the present work is to characterize a composite material developed for aerospace applications and produced by means of the resin film infusion process (RFI. Different tests have been carried out: tensile, open-hole and filled-hole tensile, compressive, openhole and filled-hole compressive. The experimental campaign has the aim to define mechanical characteristics of this RFI composite material in different conditions: environmental temperature, Hot/Wet and Cold.

  3. A method for determination of complete mechanical characteristics of heterogeneous-structured materials

    Directory of Open Access Journals (Sweden)

    M. Maj

    2009-07-01

    Full Text Available The article outlines the possibilities to evaluate by a modified low-cycle fatigue test the quality of materials characterised by different structures and the resulting mechanical properties. The method was described by computer program (MLCF, adjusted to the operating parameters of a versatile testing machine.

  4. Aviation Career Awareness Program [and Related Materials].

    Science.gov (United States)

    Petrie, Edwin T.

    The learning packet focuses on general aviation and is to be used in career awareness programs at the elementary level. It includes a document which presents a group of units on general aviation and its related careers. The units include the following: (1) aircraft manufacturing, (2) instruments and controls, (3) how airplanes fly, (4) flight…

  5. Magnetic fusion energy materials technology program annual progress report for period ending June 30, 1977

    International Nuclear Information System (INIS)

    Scott, J.L.

    1977-09-01

    The objectives of the Magnetic Fusion Energy (MFE) Materials Technology Program, which is described in this report, are to continue to solve the materials problems of the Fusion Energy Division of ORNL and to meet needs of the national MFE program, directed by the ERDA Division of Magnetic Fusion Energy (DMFE). This work is a continuation of the program described in previous annual progress reports. The principal areas of work include radiation effects, compatibility studies, materials studies related to the plasma-materials interaction, materials engineering, radiation behavior of superconducting magnet insulation, and mechanical properties of superconducting composites. The level of effort and schedules are consistent with Logic II of the DMFE Program Plan

  6. Continuum mechanical and computational aspects of material behavior

    Energy Technology Data Exchange (ETDEWEB)

    Fried, Eliot; Gurtin, Morton E.

    2000-02-10

    The focus of the work is the application of continuum mechanics to materials science, specifically to the macroscopic characterization of material behavior at small length scales. The long-term goals are a continuum-mechanical framework for the study of materials that provides a basis for general theories and leads to boundary-value problems of physical relevance, and computational methods appropriate to these problems supplemented by physically meaningful regularizations to aid in their solution. Specific studies include the following: the development of a theory of polycrystalline plasticity that incorporates free energy associated with lattice mismatch between grains; the development of a theory of geometrically necessary dislocations within the context of finite-strain plasticity; the development of a gradient theory for single-crystal plasticity with geometrically necessary dislocations; simulations of dynamical fracture using a theory that allows for the kinking and branching of cracks; computation of segregation and compaction in flowing granular materials.

  7. Analysis of transient fuel failure mechanisms: selected ANL programs

    International Nuclear Information System (INIS)

    Deitrich, L.W.

    1975-01-01

    Analytical programs at Argonne National Laboratory related to fuel pin failure mechanisms in fast-reactor accident transients are described. The studies include transient fuel pin mechanics, mechanics of unclad fuel, and mechanical effects concerning potential fuel failure propagation. (U.S.).

  8. Contact mechanics for layered materials with randomly rough surfaces.

    Science.gov (United States)

    Persson, B N J

    2012-03-07

    The contact mechanics model of Persson is applied to layered materials. We calculate the M function, which relates the surface stress to the surface displacement, for a layered material, where the top layer (thickness d) has different elastic properties than the semi-infinite solid below. Numerical results for the contact area as a function of the magnification are presented for several cases. As an application, we calculate the fluid leak rate for laminated rubber seals.

  9. Wave dynamics and composite mechanics for microstructured materials and metamaterials

    CERN Document Server

    2017-01-01

    This volume deals with topical problems concerning technology and design in construction of modern metamaterials. The authors construct the models of mechanical, electromechanical and acoustical behavior of the metamaterials, which are founded upon mechanisms existing on micro-level in interaction of elementary structures of the material. The empiric observations on the phenomenological level are used to test the created models. The book provides solutions, based on fundamental methods and models using the theory of wave propagation, nonlinear theories and composite mechanics for media with micro- and nanostructure. They include the models containing arrays of cracks, defects, with presence of micro- and nanosize piezoelectric elements and coupled physical-mechanical fields of different nature. The investigations show that the analytical, numerical and experimental methods permit evaluation of the qualitative and quantitative properties of the materials of this sort, with diagnosis of their effective characte...

  10. PHYSICAL AND MECHANICAL CHARACTERISTICS OF BUILDING MATERIALS OF HISTORIC BUILDINGS

    Directory of Open Access Journals (Sweden)

    Jiří Witzany

    2017-12-01

    Full Text Available The article presents partial results of laboratory research into physical and mechanical characteristics of materials most commonly used as walling units in masonry structures of historic and heritage buildings. Core boreholes and specimens for the laboratory research of selected characteristics were sampled from accessible places of historic buildings, which had not been restored or reconstructed. The results of the research brought new knowledge about the unreliability (variance of the properties of historical, mainly natural building materials, and, at the same time, pointed out the need for further research and extension of knowledge necessary for the assessment of residual physical and mechanical characteristics of historic masonry structures.

  11. Heavy Vehicle Propulsion Materials Program: Progress and Highlights

    International Nuclear Information System (INIS)

    D. Ray Johnson; Sidney Diamond

    2000-01-01

    The Heavy Vehicle Propulsion Materials Program was begun in 1997 to support the enabling materials needs of the DOE Office of Heavy Vehicle Technologies (OHVT). The technical agenda for the program grew out of the technology roadmap for the OHVT and includes efforts in materials for: fuel systems, exhaust aftertreatment, valve train, air handling, structural components, electrochemical propulsion, natural gas storage, and thermal management. A five-year program plan was written in early 2000, following a stakeholders workshop. The technical issues and planned and ongoing projects are discussed. Brief summaries of several technical highlights are given

  12. Abrasive wear mechanisms and surface layer structure of refractory materials after mechanical working

    International Nuclear Information System (INIS)

    Milman, Y.V.; Lotsko, D.V.

    1989-01-01

    The mechanisms of abrasive wear and surface layer structure formation after different kinds of mechanical working are considered in terms of fracture and plastic deformation mechanisms for various refractory materials. The principles for classification of abrasive wear mechanisms are proposed, the four types of wear mechanisms are distinguished for various combinations of fractures and plastic deformation types. The concept of characteristic deformation temperature t * (knee temperature) is used. Detailed examples are given of investigating the surface layer structures in grinded crystals of sapphire and molybdenum. The amorphisation tendency of the thinnest surface layer while mechanical polishing is discussed separately. 19 refs., 11 figs., 2 tabs. (Author)

  13. Mechanical Properties of Nanostructured Materials Determined Through Molecular Modeling Techniques

    Science.gov (United States)

    Clancy, Thomas C.; Gates, Thomas S.

    2005-01-01

    The potential for gains in material properties over conventional materials has motivated an effort to develop novel nanostructured materials for aerospace applications. These novel materials typically consist of a polymer matrix reinforced with particles on the nanometer length scale. In this study, molecular modeling is used to construct fully atomistic models of a carbon nanotube embedded in an epoxy polymer matrix. Functionalization of the nanotube which consists of the introduction of direct chemical bonding between the polymer matrix and the nanotube, hence providing a load transfer mechanism, is systematically varied. The relative effectiveness of functionalization in a nanostructured material may depend on a variety of factors related to the details of the chemical bonding and the polymer structure at the nanotube-polymer interface. The objective of this modeling is to determine what influence the details of functionalization of the carbon nanotube with the polymer matrix has on the resulting mechanical properties. By considering a range of degree of functionalization, the structure-property relationships of these materials is examined and mechanical properties of these models are calculated using standard techniques.

  14. Basic Mechanisms Leading to Fatigue Failure of Structural Materials

    Czech Academy of Sciences Publication Activity Database

    Polák, Jaroslav; Petráš, Roman; Mazánová, Veronika

    2016-01-01

    Roč. 69, č. 2 (2016), s. 289-294 ISSN 0972-2815. [International Conference on CREEP , FATIGUE and CREEP -FATIGUE INTERACTION /7./. Kalpakkam, 19.01.2016-22.01.2016] R&D Projects: GA ČR(CZ) GA13-23652S Institutional support: RVO:68081723 Keywords : Damage mechanism * Fatigue crack initiation * Austenitic steel * Oxide cracking Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.533, year: 2016

  15. Advanced Industrial Materials (AIM) Program: Annual progress report FY 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    In many ways, the Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven ``Vision Industries`` that use about 80% of industrial energy and generated about 90% of industrial wastes. The mission of AIM has, therefore, changed to ``Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.`` Though AIM remains essentially a National Laboratory Program, it is essential that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains reasonably healthy and productive, thanks to the superb investigators and Laboratory Program Managers. This Annual Report for FY 1995 contains the technical details of some very remarkable work by the best materials scientists and engineers in the world. Areas covered here are: advanced metals and composites; advanced ceramics and composites; polymers and biobased materials; and new materials and processes.

  16. Surface effects on the mechanical properties of nanoporous materials

    International Nuclear Information System (INIS)

    Xia Re; Li Xide; Feng Xiqiao; Qin Qinghua; Liu Jianlin

    2011-01-01

    Using the theory of surface elasticity, we investigate the mechanical properties of nanoporous materials. The classical theory of porous materials is modified to account for surface effects, which become increasingly important as the characteristic sizes of microstructures shrink to nanometers. First, a refined Timoshenko beam model is presented to predict the effective elastic modulus of nanoporous materials. Then the surface effects on the elastic microstructural buckling behavior of nanoporous materials are examined. In particular, nanoporous gold is taken as an example to illustrate the application of the proposed model. The results reveal that both the elastic modulus and the critical buckling behavior of nanoporous materials exhibit a distinct dependence on the characteristic sizes of microstructures, e.g. the average ligament width.

  17. Surface effects on the mechanical properties of nanoporous materials

    Energy Technology Data Exchange (ETDEWEB)

    Xia Re [School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072 (China); Li Xide; Feng Xiqiao [AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China); Qin Qinghua [School of Engineering, Australian National University, Canberra, ACT 0200 (Australia); Liu Jianlin, E-mail: fengxq@tsinghua.edu.cn [Department of Engineering Mechanics, China University of Petroleum, Qingdao 266555 (China)

    2011-07-01

    Using the theory of surface elasticity, we investigate the mechanical properties of nanoporous materials. The classical theory of porous materials is modified to account for surface effects, which become increasingly important as the characteristic sizes of microstructures shrink to nanometers. First, a refined Timoshenko beam model is presented to predict the effective elastic modulus of nanoporous materials. Then the surface effects on the elastic microstructural buckling behavior of nanoporous materials are examined. In particular, nanoporous gold is taken as an example to illustrate the application of the proposed model. The results reveal that both the elastic modulus and the critical buckling behavior of nanoporous materials exhibit a distinct dependence on the characteristic sizes of microstructures, e.g. the average ligament width.

  18. Transition from the mechanics of material points to the mechanics of structured particles

    Science.gov (United States)

    Somsikov, V. M.

    2016-01-01

    In this paper, necessity of creation of mechanics of structured particles is discussed. The way to create this mechanics within the laws of classical mechanics with the use of energy equation is shown. The occurrence of breaking of time symmetry within the mechanics of structured particles is shown, as well as the introduction of concept of entropy in the framework of classical mechanics. The way to create the mechanics of non-equilibrium systems in the thermodynamic approach is shown. It is also shown that the use of hypothesis of holonomic constraints while deriving the canonical Lagrange equation made it impossible to describe irreversible dynamics. The difference between the mechanics of structured particles and the mechanics of material points is discussed. It is also shown that the matter is infinitely divisible according to the laws of classical mechanics.

  19. The US fusion materials program: Status and directions

    International Nuclear Information System (INIS)

    Doran, D.G.

    1987-05-01

    The general long term objective of the Fusion Materials Program of the Office of Fusion Energy is the development of new or improved materials that will enhance the economic and environmental attractiveness of fusion as an energy source. The US Magnetic Fusion Program Plan, as augmented by the Technical Planning Activity (TPA), calls for information to be developed on critical issues such that a decision can be made by about 2005 on whether to pursue fusion as a viable energy source. Viability will be evaluated in at least four areas: technical, economic, environmental, and safety. The Fusion Materials Program addresses directly only the magnetic confinement option, although some of the information gained is applicable to the alternative approach of inertial confinement. The scope of this paper is limited to programs in which a primary concern is bulk neutron radiation effects, as opposed to those in which the primary concern is interaction of the materials with the plasma. 14 refs

  20. Microstructure and mechanical properties of SiC materials

    International Nuclear Information System (INIS)

    Yarahmadi, M.

    1985-01-01

    The effect of the microstructure on the mechanical properties of SiC materials of different chemical composition (SSiC, SiSiC, and RSiC) was investigated. Furthermore, the creep strength was determined on oxidized samples and on non-pretreated samples. (HSCH)

  1. MILLING MECHANICS OF MATERIALS ROLLED IN THICK LAYER

    Directory of Open Access Journals (Sweden)

    E. B. Lojechnikov

    2006-01-01

    Full Text Available Powder rolling conditions are systematized with the purpose of their compacting and milling. The generalized  condition of solid and free-flowing bulk material deformation is proposed in the  paper. The analytical solution of a stressed state of powder being shaped mechanically that ensures milling of its particles has been obtained.

  2. Mechanics of biopolymer materials: Single chains to bulk properties

    NARCIS (Netherlands)

    Amuasi, H.E.; Storm, C.

    2010-01-01

    We outline the first stages in the multiscale modeling of biopolymer materials, starting with the statistical mechanics of single stiff chains. In the first coarse graining step, we demonstrate how to integrate out the single polymer degrees of freedom in supramolecular assemblies of such

  3. Mechanical Characterization of Cotton Fiber/Polyester Composite Material

    Directory of Open Access Journals (Sweden)

    Altaf Hussain Rajper

    2014-04-01

    Full Text Available Development of composite from natural fiber for lower structural application is growing for long-term sustainable perspective. Cotton fiber composite material has the added advantages of high specific strength, corrosion resistance, low cost and low weight compared to glass fiber on the expense of internal components of IC engines. The primary aim of the research study is to examine the effect of the cotton fiber on mechanical properties of lower structural applications when added with the polyester resin. In this paper composite material sample has been prepared by hand Lay-Up process. A mould is locally developed in the laboratory for test sample preparation. Initially samples of polyester resin with appropriate ratio of the hardener were developed and tested. At the second stage yarns of cotton fiber were mixed with the polyester resin and sample specimens were developed and tested. Relative effect of the cotton as reinforcing agent was examined and observed that developed composite specimen possess significant improvement in mechanical properties such as tensile strength was improved as 19.78 % and modulus of elasticity was increased up to 24.81%. Through this research it was also observed that developed composite material was of ductile nature and its density decreases up to 2.6%. Results from this study were compared with relevant available advanced composite materials and found improved mechanical properties of developed composite material

  4. Mechanical characterization of hydroxyapatite, thermoelectric materials and doped ceria

    Science.gov (United States)

    Fan, Xiaofeng

    For a variety of applications of brittle ceramic materials, porosity plays a critical role structurally and/or functionally, such as in engineered bone scaffolds, thermoelectric materials and in solid oxide fuel cells. The presence of porosity will affect the mechanical properties, which are essential to the design and application of porous brittle materials. In this study, the mechanical property versus microstructure relations for bioceramics, thermoelectric (TE) materials and solid oxide fuel cells were investigated. For the bioceramic material hydroxyapatite (HA), the Young's modulus was measured using resonant ultrasound spectroscopy (RUS) as a function of (i) porosity and (ii) microcracking damage state. The fracture strength was measured as a function of porosity using biaxial flexure testing, and the distribution of the fracture strength was studied by Weibull analysis. For the natural mineral tetrahedrite based solid solution thermoelectric material (Cu10Zn2As4S13 - Cu 12Sb4S13), the elastic moduli, hardness and fracture toughness were studied as a function of (i) composition and (ii) ball milling time. For ZiNiSn, a thermoelectric half-Heusler compound, the elastic modulus---porosity and hardness---porosity relations were examined. For the solid oxide fuel cell material, gadolina doped ceria (GDC), the elastic moduli including Young's modulus, shear modulus, bulk modulus and Poisson's ratio were measured by RUS as a function of porosity. The hardness was evaluated by Vickers indentation technique as a function of porosity. The results of the mechanical property versus microstructure relations obtained in this study are of great importance for the design and fabrication of reliable components with service life and a safety factor. The Weibull modulus, which is a measure of the scatter in fracture strength, is the gauge of the mechanical reliability. The elastic moduli and Poisson's ratio are needed in analytical or numerical models of the thermal and

  5. JAERI/KEK target material program overview

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Kogawa, Hiroyuki; Sasa, Toshinobu

    2001-01-01

    Mercury target was designed for megawatt neutron scattering facility in JAERI/KEK spallation neutron source. The incident proton energy and current are 3 GeV and 333 μA, respectively: the total proton energy is 1 MW in short pulses at a frequency of 25 Hz. Under the guide rule the mercury target was designed: the maximum temperature of target window is 170degC and induced stresses for the type 316 stainless steel are within limits of design guide. In order to demonstrate ADS (Accelerator Driven Systems) transmutation critical and engineering facilities have been designed conceptually. In engineering facility lead-bismuth spallation target station is to be planned. Objective to build the facility is to demonstrate material irradiation. According to neutronics calculation irradiation damage of the target vessel window will be 5 dpa per year. (author)

  6. Japanese program of materials research for fusion reactors

    International Nuclear Information System (INIS)

    Hasiguti, R.R.

    1982-01-01

    The Japanese program of materials research for fusion reactors is described based on the report to the Nuclear Fusion Council, the project research program of the Ministry of Education, Science and Culture, and other official documents. The alloy development for the first wall and its radiation damage are the main topics discussed in this paper. Materials viewpoints for the Japanese Tokamak facilities and the problems of irradiation facilities are also discussed. (orig.)

  7. Volume Resistivity and Mechanical Behavior of Epoxy Nanocomposite Materials

    Directory of Open Access Journals (Sweden)

    M. F. Abdelkarim

    2015-04-01

    Full Text Available Electrical and mechanical properties of polymer composite materials are investigated through the determination of resistivity and hardness for composites samples. Epoxy composite samples have been prepared with different concentrations of certain inorganic fillers such as; Titanium dioxide (TiO2 and Silica (SiO2, of various size (micro, nano and hybrid to study the electrical and mechanical behavior. The volume resistivity reaches 3.23×1014 ohm.cm for the micro silica composite. Surface of composite material has been mechanically examined by hardness test. The results show that the resistivity of microcomposites and nanocmposites are increased with the decrease of filler concentration. But the resistivity of hybrid composites is increased with the increase of filler concentration. Maximum hardness value was obtained from hybrid silica composite with 0.1% filler concentration.

  8. A comparative evaluation of mechanical properties of nanofibrous materials

    Science.gov (United States)

    Lyubun, German P.; Bessudnova, Nadezda O.

    2014-01-01

    Restoration or replacement of lost or damaged hard tooth tissues remain a reconstructive clinical dentistry challenge. One of the most promising solutions to this problem is the development of novel concepts and methodologies of tissue engineering for the synthesis of three-dimensional graft constructs that are equivalent to original organs and tissues. This structural and functional compatibility can be reached by producing ultra-thin polymer filament scaffolds. This research aims through a series of studies to examine different methods of polymer filament material special preparation and test mechanical properties of the produced materials subjected to a tensile strain. Nanofibrous material preparation using chemically pure acetone and mixtures of ethanol/water has shown no significant changes in sample surface morphology. The high temperature impact on material morphology has resulted in the modification of fiber structure. In the course of mechanical tests it has been revealed the dependence of the material strength on the spinning solution compositions. The results achieved point to the possibility to develop nanofibrous materials with required parameters changing the methodology of spinning solution production.

  9. Program strategy document for the Nuclear Materials Transportation Technology Center

    International Nuclear Information System (INIS)

    Jefferson, R.M.

    1979-07-01

    A multiyear program plan is presented which describes the program of the Nuclear Materials Transportation Technology Center (TIC) at Sandia Laboratories. The work element plans, along with their corresponding work breakdown structures, are presented for TTC activities in the areas of Technology and Information Center, Systems Development, Technology, and Institutional Issues for the years from 1979 to 1985

  10. FWP executive summaries: Basic energy sciences materials sciences programs

    Energy Technology Data Exchange (ETDEWEB)

    Samara, G.A.

    1996-02-01

    This report provides an Executive Summary of the various elements of the Materials Sciences Program which is funded by the Division of Materials Sciences, Office of Basic Energy Sciences, U.S. Department of Energy at Sandia National Laboratories, New Mexico.

  11. Annotated Bibliography of Materials for Elementary Foreign Language Programs.

    Science.gov (United States)

    Dobb, Fred

    An annotated bibliography contains about 70 citations of instructional materials and materials concerning curriculum development for elementary school foreign language programs. Citations are included for Arabic, classical languages, French, German, Hebrew, Italian, Japanese, and Spanish. Items on exploratory language courses and general works on…

  12. Fossil Energy Advanced Research and Technology Development Materials Program

    Energy Technology Data Exchange (ETDEWEB)

    Cole, N.C.; Judkins, R.R. (comps.)

    1992-12-01

    Objective of this materials program is to conduct R and D on materials for fossil energy applications with focus on longer-term and generic needs of the various fossil fuel technologies. The projects are organized according to materials research areas: (1) ceramics, (2) new alloys: iron aluminides, advanced austenitics and chromium niobium alloys, and (3) technology development and transfer. Separate abstracts have been prepared.

  13. Mechanical properties of LMR structural materials at high temperature

    International Nuclear Information System (INIS)

    Kim, D. W.; Kuk, I. H.; Ryu, W. S. and others

    1999-03-01

    Austenitic stainless is used for the structural material of liquid metal reactor (LMR) because of good mechanical properties at high temperature. Stainless steel having more resistant to temperature by adding minor element has been developing for operating the LMR at higher temperature. Of many elements, nitrogen is a prospective element to modify type 316L(N) stainless steel because nitrogen is the most effective element for solid solution and because nitrogen retards the precipitation of carbide at grain boundary. Ti, Nb, and V are added to improve creep properties by stabilizing the carbides through forming MC carbide. Testing techniques of tensile, fatigue, creep, and creep-fatigue at high temperature are difficult. Moreover, testing times for creep and creep-fatigue tests are very long up to several tens of thousands hours because creep and creep-fatigue phenomena are time-dependent damage mechanism. So, it is hard to acquire the material data for designing LMR systems during a limited time. In addition, the integrity of LMR structural materials at the end of LMR life has to be predicted from the laboratory data tested during the short term because there is no data tested during 40 years. Therefore, the effect of elements on mechanical properties at high temperature was reviewed in this study and many methods to predict the long-term behaviors of structural materials by simulated modelling equation is shown in this report. (author). 32 refs., 9 tabs., 38 figs

  14. Generation IV Reactors Integrated Materials Technology Program Plan: Focus on Very High Temperature Reactor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Corwin, William R [ORNL; Burchell, Timothy D [ORNL; Katoh, Yutai [ORNL; McGreevy, Timothy E [ORNL; Nanstad, Randy K [ORNL; Ren, Weiju [ORNL; Snead, Lance Lewis [ORNL; Wilson, Dane F [ORNL

    2008-08-01

    the structural materials needed to ensure their safe and reliable operation. The focus of this document will be the overall range of DOE's structural materials research activities being conducted to support VHTR development. By far, the largest portion of material's R&D supporting VHTR development is that being performed directly as part of the Next-Generation Nuclear Plant (NGNP) Project. Supplementary VHTR materials R&D being performed in the DOE program, including university and international research programs and that being performed under direct contracts with the American Society for Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, will also be described. Specific areas of high-priority materials research that will be needed to deploy the NGNP and provide a basis for subsequent VHTRs are described, including the following: (1) Graphite: (a) Extensive unirradiated materials characterization and assessment of irradiation effects on properties must be performed to qualify new grades of graphite for nuclear service, including thermo-physical and mechanical properties and their changes, statistical variations from billot-to-billot and lot-to-lot, creep, and especially, irradiation creep. (b) Predictive models, as well as codification of the requirements and design methods for graphite core supports, must be developed to provide a basis for licensing. (2) Ceramics: Both fibrous and load-bearing ceramics must be qualified for environmental and radiation service as insulating materials. (3) Ceramic Composites: Carbon-carbon and SiC-SiC composites must be qualified for specialized usage in selected high-temperature components, such as core stabilizers, control rods, and insulating covers and ducting. This will require development of component-specific designs and fabrication processes, materials characterization, assessment of environmental and irradiation effects, and establishment of codes and standards for materials testing and design

  15. Analysis of Mechanical Properties of Fabrics of Different Raw Material

    Directory of Open Access Journals (Sweden)

    Aušra ADOMAITIENĖ

    2011-07-01

    Full Text Available The study analyzes dependence of mechanical properties (breaking force, elongation at break, static friction force and static friction coefficient on integrated fabric structure factor j and raw material density r, among the fabrics of different raw material (cotton, wool, polypropylene, polyester and polyacrylnitrile and woven in different conditions. The received results demonstrate that sometimes strong dependences exist (wool, polypropylene and polyacrylnitrile, whereas in some cases (cotton and polyester there is no correlation. It was also discovered that the breaking force and elongation at break in the direction of weft increase, when fabric structure becomes more rigid. In the meantime variations of the curves in the direction of warp are insignificant. Regarding static friction force and static friction coefficient (found in two cases, when fabrics were rubbing against leather and materials, it was discovered that consistency of the curves is irregular, i. e. they either increase or decrease, when integrated fabric structure factor j growth. It was also identified that some dependences are not strong and relationship between explored and analyzed factors does not exist. Variation of all these mechanical properties with respect to material density r enables to conclude that increase of material density r results in poor dependences or they are whatsoever non-existent.http://dx.doi.org/10.5755/j01.ms.17.2.487

  16. Fusion reactor materials program plan. Section 2. Damage analysis and fundamental studies

    International Nuclear Information System (INIS)

    1978-07-01

    The scope of this program includes: (1) Development of procedures for characterizing neutron environments of test facilities and fusion reactors, (2) Theoretical and experimental investigations of the influence of irradiation environment on damage production, damage microstructure evolution, and mechanical and physical property changes, (3) Identification and, where appropriate, development of essential nuclear and materials data, and (4) Development of a methodology, based on damage mechanisms, for correlating the mechanical behavior of materials exposed to diverse test environments and projecting this behavior to magnetic fusion reactor (MFR) environments. Some major problem areas are addressed

  17. Measurement of Mechanical Properties of Cantilever Shaped Materials

    Directory of Open Access Journals (Sweden)

    Thomas Thundat

    2008-05-01

    Full Text Available Microcantilevers were first introduced as imaging probes in Atomic Force Microscopy (AFM due to their extremely high sensitivity in measuring surface forces. The versatility of these probes, however, allows the sensing and measurement of a host of mechanical properties of various materials. Sensor parameters such as resonance frequency, quality factor, amplitude of vibration and bending due to a differential stress can all be simultaneously determined for a cantilever. When measuring the mechanical properties of materials, identifying and discerning the most influential parameters responsible for the observed changes in the cantilever response are important. We will, therefore, discuss the effects of various force fields such as those induced by mass loading, residual stress, internal friction of the material, and other changes in the mechanical properties of the microcantilevers. Methods to measure variations in temperature, pressure, or molecular adsorption of water molecules are also discussed. Often these effects occur simultaneously, increasing the number of parameters that need to be concurrently measured to ensure the reliability of the sensors. We therefore systematically investigate the geometric and environmental effects on cantilever measurements including the chemical nature of the underlying interactions. To address the geometric effects we have considered cantilevers with a rectangular or circular cross section. The chemical nature is addressed by using cantilevers fabricated with metals and/or dielectrics. Selective chemical etching, swelling or changes in Young’s modulus of the surface were investigated by means of polymeric and inorganic coatings. Finally to address the effect of the environment in which the cantilever operates, the Knudsen number was determined to characterize the molecule-cantilever collisions. Also bimaterial cantilevers with high thermal sensitivity were used to discern the effect of temperature

  18. Industry-led program recycles used oil materials

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    The Alberta Used Oil Management Association (AUOMA) is running an industry-led program for recycling used oil filters, containers and used oil. The objective of the program is to help develop an infrastructure that will make recycling simple and convenient for consumers of oil materials. It was estimated that millions of litres of used oil are improperly discarded into the Alberta environment. The program is also aimed at increasing public awareness of the importance of recycling used oil materials, particularly to those consumers who change their own motor oil. By the end of 1997 AUOMA expects to open about 50 recycling centres called EcoCentres. An environmental handling charge (EHC) will be paid to AUOMA by wholesale suppliers on the first sale of oil materials in Alberta. The EHC will be the only funds used to support the program

  19. Fusion material development program in the broader approach activities

    Energy Technology Data Exchange (ETDEWEB)

    Nishitani, T. [Directorates of Fusion Energy Research: Naka, Ibaraki, Japan Atomic Energy Agency, Naka, Ibaraki (Japan); Tanigawa, H.; Jitsukawa, S. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Hayashi, K.; Takatsu, H. [Fusion Research and Development Directorate, Japan Momie Energy Agency, Ibaraki-ken (Japan); Yamanishi, T. [Tritium Process Laboratory, Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki-ken (Japan); Tsuchiya, K. [Directorates of Fusion Energy Research, JAEA, Higashi-ibaraki-gun, Ibaraki-ken (Japan); MoIslang, A. [Forschungszentrum Karlsruhe GmbH, FZK, Karlsruhe (Germany); Baluc, N. [EPFL-Ecole Polytechnique Federale de Lausanne, Association Euratom-Confederation Suisse, UHD - CRPP, PPB, Lausanne (Switzerland); Pizzuto, A. [ENEA CR Frascat, Frascati (Italy); Hodgson, E.R. [CIEMAT-Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Association Euratom-CIEMAT, Madrid (Spain); Lasser, R.; Gasparotto, M. [EFDA CSU Garching (Germany)

    2007-07-01

    Full text of publication follows: The world fusion community is now launching construction of ITER, the first nuclear-grade fusion machine in the world. In parallel to the ITER program, Broader Approach (BA) activities are initiated by EU and Japan, mainly at Rokkasho BA site in Japan. The BA activities include the International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities (IFMIF-EVEDA), the International Fusion Energy Research Center (IFERC), and the Satellite Tokamak. IFERC consists of three sub project; a DEMO Design and R and D coordination Center, a Computational Simulation Center, and an ITER Remote Experimentation Center. Technical R and Ds mainly on fusion materials will be implemented as a part of the DEMO Design and R and D coordination Center. Based on the common interest of each party toward DEMO, R and Ds on a) reduced activation ferritic martensitic (RAFM) steels as a DEMO blanket structural material, SiCf/SiC composites, advanced tritium breeders and neutron multiplier for DEMO blankets, and Tritium Technology were selected and assessed by European and Japanese experts. In the R and D on the RAFM steels, the fabrication technology, techniques to incorporate the fracture/rupture properties of the irradiated materials, and methods to predict the deformation and fracture behaviors of structures under irradiation will be investigated. For SiCf/SiC composites, standard methods to evaluate high-temperature and life-time properties will be developed. Not only for SiCf/SiC but also related ceramics, physical and chemical properties such as He and H permeability and absorption will be investigated under irradiation. As the advanced tritium breeder R and D, Japan and EU plan to establish the production technique for advanced breeder pebbles of Li{sub 2}TiO{sub 3} and Li{sub 4}SiO{sub 4}, respectively. Also physical, chemical, and mechanical properties will be investigated for produced breeder pebbles. For the

  20. Mechanical behavior of nanotwinned materials – experimental and computational approaches

    Energy Technology Data Exchange (ETDEWEB)

    Yavas, Hakan [Iowa State Univ., Ames, IA (United States)

    2016-12-17

    Nanotwinned materials exhibit high strength combined with excellent thermal stability, making them potentially attractive for numerous applications. When deposited on cold substrates at high rates, for example, silver films can be prepared with a high-density of growth twins with an average twin boundary spacing of less than 10 nm. These films show a very strong {111} texture, with the twin boundaries being perpendicular to the growth direction. The origins of superior mechanical and thermal properties of nanotwinned materials, however, are not yet fully understood and need further improvements.

  1. Mechanical behaviour of new zirconia-hydroxyapatite ceramic materials

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, J.A.; Morejon, L. [La Habana Univ. (Cuba). Centro de Biomateriales; Martinez, S. [Barcelona Univ. (Spain). Dept. Cristallografia, Mineralogia; Ginebra, M.P.; Carlsson, N.; Fernandez, E.; Planell, J.A. [Universidad Politecnica de Cataluna, Barcelona (Spain). CREB; Clavaguera-Mora, M.T.; Rodriguez-Viejo, J. [Universitat Autonoma de Barcelona (Spain). Dept. de Fisica

    2001-07-01

    In this work a new zirconia-hydroxyapatite ceramic material was obtained by uniaxial pressing and sintering in humid environment. The powder X-ray diffraction (XRD) patterns and infrared spectra (FT-IR) showed that the hydroxyapatite (HA) is the only calcium phosphate phase present. The fracture toughness for HA with 20 wt.% of magnesia partially stabilised zirconia (Mg-PSZ) was around 2.5 times higher than those obtained for HA pure, also the highest value of bending strength (160 MPa) was obtained for material reinforced with Mg-PSZ. For the MgPSZ-HA (20%) the fracture mechanism seems to be less transgranular. (orig.)

  2. Advanced Industrial Materials (AIM) Program. Annual progress report, FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Sorrell, C.A.

    1995-05-01

    The Advanced Industrial Materials Program is a part of the Office of Industrial Technologies (OIT), Energy Efficiency and Renewable Energy in the Department of Energy. The mission of the AIM Program is to conduct applied research, development, and applications engineering work, in partnership with industry, to commercialize new or improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. AIM is responsible for identifying, supporting, and coordinating multidisciplinary projects to solve identified industrial needs and transferring the technology to the industrial sector. Program investigators in the DOE National Laboratories are working closely with approximately 100 companies, including 15 partners in Cooperative Research and Development Agreements. Work is being done in a wide variety of materials technologies, including intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The Program supports other efforts in the Office of Industrial Technologies to assist the energy consuming process industries, including forest products, glass, steel, aluminum, foundries, chemicals, and refineries. To support OITs {open_quotes}Industries of the Future{close_quotes} initiatives and to improve the relevance of materials research, assessments of materials needs and opportunities in the process industries are being made. These assessments are being used for program planning and priority setting; support of work to satisfy those needs is being provided. Many new materials that have come into the marketplace in recent years, or that will be available for commercial use within a few more years, offer substantial benefits to society. This document contains 28 reports on advanced materials research. Individual reports have been processed separately for entry onto the Department of Energy databases.

  3. Glucocorticoids and fetal programming part 2: Mechanisms.

    Science.gov (United States)

    Moisiadis, Vasilis G; Matthews, Stephen G

    2014-07-01

    The lifelong health of an individual is shaped during critical periods of development. The fetus is particularly susceptible to internal and external stimuli, many of which can alter developmental trajectories and subsequent susceptibility to disease. Glucocorticoids are critical in normal development of the fetus, as they are involved in the growth and maturation of many organ systems. The surge in fetal glucocorticoid levels that occurs in most mammalian species over the last few days of pregnancy is an important developmental switch leading to fundamental changes in gene regulation in many organs, including the brain. These changes are important for the transition to postnatal life. Exposure of the fetus to increased levels of glucocorticoids, resulting from maternal stress or treatment with synthetic glucocorticoids, can lead to long-term 'programming' of hypothalamic-pituitary-adrenal function and behaviours. Glucocorticoids act at multiple levels within the fetal brain. Growing evidence indicates that they can exert powerful effects on the epigenome, including on DNA methylation, histone acetylation and microRNA, to influence gene expression. Such influences probably represent a critical component of the 'programming' process, and might be partly responsible for the transgenerational effects of antenatal glucocorticoid exposure on neurologic, cardiovascular and metabolic function.

  4. Processing and nanostructure influences on mechanical properties of thermoelectric materials

    Science.gov (United States)

    Schmidt, Robert David

    Thermoelectric (TE) materials are materials that can generate an electric current from a thermal gradient, with possible service in recovery of waste heat such as engine exhaust. Significant progress has been made in improving TE conversion efficiency, typically reported according to the figure of merit, ZT, with several recent papers publishing ZT values above 2. Furthermore, cost reductions may be made by the use of lower cost elements such as Mg, Si, Sn, Pb, Se and S in TE materials, while achieving ZT values between 1.3 and 1.8. To be used in a device, the thermoelectric material must be able to withstand the applied thermal and mechanical forces without failure. However, these materials are brittle, with low fracture toughness typically less than 1.5 MPa-m1/2, and often less than 0.5 MPa-m1/2. For comparison, window glass is approximately 0.75 MPa-m1/2. They have been optimized with nanoprecipitates, nanoparticles, doping, alterations in stoichiometry, powder processing and other techniques, all of which may alter the mechanical properties. In this study, the effect of SiC nanoparticle additions in Mg2Si, SnTe and Ag nanoparticle additions in the skutterudite Ba0.3Co 4Sb12 on the elastic moduli, hardness and fracture toughness are measured. Large changes (˜20%) in the elastic moduli in SnTe 1+x as a function of x at 0 and 0.016 are shown. The effect on mechanical properties of doping and precipitates of CdS or ZnS in a PbS or PbSe matrix have been reported. Changes in sintering behavior of the skutterudite with the Ag nanoparticle additions were explored. Possible liquid phase sintering, with associated benefits in lower processing temperature, faster densification and lower cost, has been shown. A technique has been proposed for determining additional liquid phase sintering aids in other TE materials. The effects of porosity, grain size, powder processing method, and sintering method were explored with YbAl3 and Ba0.3Co4Sb 12, with the porosity dependence of

  5. Mechanical characterization of composite materials by optical techniques: A review

    Science.gov (United States)

    Bruno, Luigi

    2018-05-01

    The present review provides an overview of work published in recent years dealing with the mechanical characterization of composite materials performed by optical techniques. The paper emphasizes the strengths derived from the employment of full-field methods when the strain field of an anisotropic material must be evaluated. This is framed in contrast to the use of conventional measurement techniques, which provide single values of the measured quantities unable to offer thorough descriptions of deformation distribution. The review outlines the intensity and articulation of work in this research field to date and its ongoing importance not only in the academy, but also in industrial sectors where composite materials represent a strategic resource for development.

  6. Thermodynamical aspects of modeling the mechanical response of granular materials

    International Nuclear Information System (INIS)

    Elata, D.

    1995-01-01

    In many applications in rock physics, the material is treated as a continuum. By supplementing the related conservation laws with constitutive equations such as stress-strain relations, a well-posed problem can be formulated and solved. The stress-strain relations may be based on a combination of experimental data and a phenomenological or micromechanical model. If the model is physically sound and its parameters have a physical meaning, it can serve to predict the stress response of the material to unmeasured deformations, predict the stress response of other materials, and perhaps predict other categories of the mechanical response such as failure, permeability, and conductivity. However, it is essential that the model be consistent with all conservation laws and consistent with the second law of thermodynamics. Specifically, some models of the mechanical response of granular materials proposed in literature, are based on intergranular contact force-displacement laws that violate the second law of thermodynamics by permitting energy generation at no cost. This diminishes the usefulness of these models as it invalidates their predictive capabilities. [This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48.

  7. Mechanical and Fatigue Properties of Additively Manufactured Metallic Materials

    Science.gov (United States)

    Yadollahi, Aref

    This study aims to investigate the mechanical and fatigue behavior of additively manufactured metallic materials. Several challenges associated with different metal additive manufacturing (AM) techniques (i.e. laser-powder bed fusion and direct laser deposition) have been addressed experimentally and numerically. Experiments have been carried out to study the effects of process inter-layer time interval--i.e. either building the samples one-at-a-time or multi-at-a-time (in-parallel)--on the microstructural features and mechanical properties of 316L stainless steel samples, fabricated via a direct laser deposition (DLD). Next, the effect of building orientation--i.e. the orientation in which AM parts are built--on microstructure, tensile, and fatigue behaviors of 17-4 PH stainless steel, fabricated via a laser-powder bed fusion (L-PBF) method was investigated. Afterwards, the effect of surface finishing--here, as-built versus machined--on uniaxial fatigue behavior and failure mechanisms of Inconel 718 fabricated via a laser-powder bed fusion technique was sought. The numerical studies, as part of this dissertation, aimed to model the mechanical behavior of AM materials, under monotonic and cyclic loading, based on the observations and findings from the experiments. Despite significant research efforts for optimizing process parameters, achieving a homogenous, defect-free AM product--immediately after fabrication--has not yet been fully demonstrated. Thus, one solution for ensuring the adoption of AM materials for application should center on predicting the variations in mechanical behavior of AM parts based on their resultant microstructure. In this regard, an internal state variable (ISV) plasticity-damage model was employed to quantify the damage evolution in DLD 316L SS, under tensile loading, using the microstructural features associated with the manufacturing process. Finally, fatigue behavior of AM parts has been modeled based on the crack-growth concept

  8. Microstructural and mechanical characterization of laser deposited advanced materials

    Science.gov (United States)

    Sistla, Harihar Rakshit

    Additive manufacturing in the form of laser deposition is a unique way to manufacture near net shape metallic components from advanced materials. Rapid solidification facilitates the extension of solid solubility, compositional flexibility and decrease in micro-segregation in the melt among other advantages. The current work investigates the employment of laser deposition to fabricate the following: 1. Functionally gradient materials: This allows grading dissimilar materials compositionally to tailor specific properties of both these materials into a single component. Specific compositions of the candidate materials (SS 316, Inconel 625 and Ti64) were blended and deposited to study the brittle intermetallics reported in these systems. 2. High entropy alloys: These are multi- component alloys with equiatomic compositions of 5 or more elements. The ratio of Al to Ni was decreased to observe the transition of solid solution from a BCC to an FCC crystal structure in the AlFeCoCrNi system. 3. Structurally amorphous alloys: Zr-based metallic glasses have been reported to have high glass forming ability. These alloys have been laser deposited so as to rapidly cool them from the melt into an amorphous state. Microstructural analysis and X-ray diffraction were used to study the phase formation, and hardness was measured to estimate the mechanical properties.

  9. Damage mechanisms and metallic materials development in multiphase flow

    International Nuclear Information System (INIS)

    Zheng, Yugui; Liu, Wei; Yao, Zhiming; Ke, Wei

    2002-01-01

    The investigation on the synergistic effects among corrosion, slurry erosion and cavitation erosion has special significance for hydraulic turbines operated in Yangtze River and Yellow River where the high concentration solid particles exist in water. Two typical metallic materials i.e. Cr-Mn-N stainless steel and Ni-Ti shapememory-alloy, and two typical materials used for hydraulic turbines 20SiMn and 0Cr13Ni5Mo as compared materials were selected in order to investigate the roles of work-hardening ability and martensitic transformation as well as pseudoelastics in damage mechanism in multiphase flow. Both modified rotating disk rig and ultrasonic vibration facility were used to simulate the possible damage mechanism of materials in multiphase flow. The effects of corrosion on cavitation erosion were investigated through adding 3wt% NaCl. The degradation mechanism was analyzed by electrochemical test, SEM observation, hardness and roughness measurement. The results showed that there was a strong synergistic interaction among electrochemical corrosion, slurry erosion and cavitation erosion for 20SiMn in liquid-solid two-phase medium. In contrast, corrosion played little role for 0Cr13Ni5Mo. Cr-Mn-N stainless steel with high Mn content showed better resistance to cavitation erosion and slurry erosion than 0Cr13Ni5Mo, which was mainly due to its good work-hardening ability as well as strain-induced martensite transformation. The cavitation micro-cracks for Cr-Mn-N stainless steel were parallel to the specimen surface in contrast with 0Cr13Ni5Mo whose micro-cracks were perpendicular to the surface. Ni-Ti alloy with pseudoelasticity showed excellent resistance to combined interaction of cavitation erosion and slurry erosion

  10. Nuclear materials control and accountability internal audit program

    International Nuclear Information System (INIS)

    Barham, M.A.; Abbott, R.R.

    1991-01-01

    This paper reports that the Department of Energy Order (DOE) 5633.3, Control and Accountability for Nuclear Materials, includes several requirements for development and implementation of an internal audit program. Martin Marietta Energy System, Inc., manages five sites in Tennessee, Kentucky, and Ohio for the DOE Field Office, Oak Ridge and has a Central Nuclear Materials Control and Accountability (NMC and A) Manager with matrixed responsibility for the NMC and A program at the five sites. The Energy Systems Central NMC and A Manager has developed an NMC and A Internal Audit Handbook which defines the functional responsibilities, performance criteria, and reporting and documentation requirements for the Energy Systems NMC and A Internal Audit Program. The initial work to develop and implement these standards was tested at the K-25 Site when the site hired an internal auditor to meet the DOE requirements for an NMC and A Internal Audit program

  11. Thermal-mechanical fatigue of high temperature structural materials

    Science.gov (United States)

    Renauld, Mark Leo

    Experimental and analytical methods were developed to address the effect of thermal-mechanical strain cycling on high temperature structural materials under uniaxial and biaxial stress states. Two materials were used in the investigation, a nickel-base superalloy of low ductility, IN-738LC and a high ductility material, 316 stainless steel. A uniaxial life prediction model for the IN-738LC material was based on tensile hysteresis energy measured in stabilized, mid-life hysteresis loops. Hold-time effects and temperature cycling were incorporated in the hysteresis energy approach. Crack growth analysis was also included in the model to predict the number of TMF cycles to initiate and grow a fatigue crack through the coating. The nickel-base superalloy, IN-738LC, was primarily tested in out-of-phase (OP) TMF with a temperature range from 482-871sp°C (900-1600sp°F) under continuous and compressive hold-time cycling. IN-738LC fatigue specimens were coated either with an aluminide, NiCoCrAlHfSi overlay or CoNiCrAlY overlay coating on the outer surface of the specimen. Metallurgical failure analysis via optical and scanning electron microscopy, was used to characterize failure behavior of both substrate and coating materials. Type 316 SS was subjected to continuous biaxial strain cycling with an in-phase (IP) TMF loading and a temperature range from 399-621sp°C (750-1150sp°F). As a result, a biaxial TMF life prediction model was proposed on the basis of an extended isothermal fatigue model. The model incorporates a frequency effect and phase factors to assess the different damage mechanisms observed during TMF loading. The model was also applied to biaxial TMF data generated on uncoated IN-738LC.

  12. Materials and corrosion programs sponsored by the Gas Research Institute

    International Nuclear Information System (INIS)

    Flowers, A.

    1980-01-01

    The paper deals briefly with the Gas Research Institute and its research in materials and corrosion. As a not-for-profit organization, the Gas Research Institute plans, finances, and manages applied and basic research and technological development programs associated with gaseous fuels. These programs are in the general areas of production, transportation, storage, utilization and conservation of natural and manufactured gases and related products. Research results, whether experimental or analytical, are evaluated and publicly disseminated. Materials and corrosion research is concentrated in the SNG from Coal and Non-fossil Hydrogen subprograms

  13. Parts, Materials, and Processes Control Program for Expendable Launch Vehicles

    Science.gov (United States)

    2015-05-21

    cycle cost ; and 4. Improve procurement and test of small quantities of parts and materials that meet system requirements. This document supersedes...the reliability of program PMP to reduce PMP failures at all levels of assembly and test 3. Reduce program lifecycle cost 4. Improve procurement and...part shall be procured in single lots directly from the manufacturer or its authorized franchised distributor. The contractor shall be able to

  14. Nuclear Materials Stewardship Within the DOE Environmental Management Program

    International Nuclear Information System (INIS)

    Bilyeu, J. D.; Kiess, T. E.; Gates, M. L.

    2002-01-01

    The Department of Energy (DOE) Environmental Management (EM) Program has made significant progress in planning disposition of its excess nuclear materials and has recently completed several noteworthy studies. Since establishment in 1997, the EM Nuclear Material Stewardship Program has developed disposition plans for excess nuclear materials to support facility deactivation. All nuclear materials have been removed from the Miamisburg Environmental Management Project (Mound), and disposition planning is nearing completion for the Fernald Environmental Management Project and the Rocky Flats Environmental Technology Site. Only a few issues remain for materials at the Hanford and Idaho sites. Recent trade studies include the Savannah River Site Canyons Nuclear Materials Identification Study, a Cesium/Strontium Management Alternatives Trade Study, a Liquid Technical Standards Trade Study, an Irradiated Beryllium Reflectors with Tritium study, a Special Performance Assessment Required Trade Study, a Neutron Source Trade Study, and development of discard criteria for uranium. A Small Sites Workshop was also held. Potential and planned future activities include updating the Plutonium-239 storage study, developing additional packaging standards, developing a Nuclear Material Disposition Handbook, determining how to recover or dispose of Pu-244 and U-233, and working with additional sites to define disposition plans for their nuclear materials

  15. Plutonium-bearing materials feed report for the DOE Fissile Materials Disposition Program alternatives

    International Nuclear Information System (INIS)

    Brough, W.G.; Boerigter, S.T.

    1995-01-01

    This report has identified all plutonium currently excess to DOE Defense Programs under current planning assumptions. A number of material categories win clearly fan within the scope of the MD (Materials Disposition) program, but the fate of the other categories are unknown at the present time. MD planning requires that estimates be made of those materials likely to be considered for disposition actions so that bounding cases for the PEIS (Programmatic Environmental Impact Statement) can be determined and so that processing which may be required can be identified in considering the various alternatives. A systematic analysis of the various alternatives in reachmg the preferred alternative requires an understanding of the possible range of values which may be taken by the various categories of feed materials. One table identifies the current total inventories excess to Defense Program planning needs and represents the bounding total of Pu which may become part of the MD disposition effort for all materials, except site return weapons. The other categories, principally irradiated fuel, rich scrap, and lean scrap, are discussed. Another table summarizes the ranges and expected quantities of Pu which could become the responsibility of the MD program. These values are to be used for assessing the impact of the various alternatives and for scaling operations to assess PEIS impact. Determination of the actual materials to be included in the disposition program will be done later

  16. OCRWM Science and Technology Program Cementitious Materials Technologies

    International Nuclear Information System (INIS)

    DOE

    2004-01-01

    This potential project will develop and test cost effective cementitious materials for construction of Yucca Mountain (YM) inverts, drift liners, and bulkheads. These high silica cementitious materials will be designed to buffer the pH and Eh of the groundwater, to slow corrosion of waste packages (WP), and to retard radionuclide migration. While being compatible with YM repository systems, these materials are expected to be less expensive to produce, and as strong, and more durable than ordinary Portland Cement (OPC). Therefore, building out the repository with these cementitious materials may significantly reduce these costs and reduce uncertainty in short-( 10,000 yr) repository performance. Both laboratory development and natural analog studies are anticipated using a unique combination of expertise at ORNL, UT, UC Berkeley, and Minatom to develop and test high-silica hydraulic, cementitious binders for use at YM. The major tasks of this project are to (1) formulate and make candidate cementitious materials using high-silica hydraulic hinders, (2) measure the physical and chemical properties of these materials, (3) expose combinations of these materials and WP materials to static and flowing YM groundwater at temperatures consistent with the expected repository conditions, (4) examine specimens of both the cementitious materials and WP materials periodically for chemical and mineralogical changes to determine reaction mechanisms and kinetics, and (5) predict the long-term performance of the material by thermodynamic and transport modeling and by comparisons with natural analogs

  17. An Interdisciplinary Program in Materials Science at James Madison University.

    Science.gov (United States)

    Hughes, Chris

    2008-03-01

    Over the past decade a core group of faculty at James Madison University has created an interdisciplinary program in materials science that provides our students with unique courses and research experiences that augment the existing, high-quality majors in physics and astronomy, chemistry and biochemistry, geology and environmental science, mathematics and statistics, and integrated science and technology. The university started this program by creating a Center for Materials Science whose budget is directly allocated by the provost. This source of funds acts as seed money for research, support for students, and a motivating factor for each of the academic units to support the participation of their faculty in the program. Courses were created at the introductory and intermediate level that are cross-listed by the departments to encourage students to enroll in them as electives toward their majors. Furthermore, the students are encouraged to participate in undergraduate research in materials since this is the most fundamental unifying theme across the disciplines. This talk will cover some of the curricular innovations that went into the design of the program to make it successful, examples of faculty and student research and how that feeds back into the classroom, and success stories of the interactions that have developed between departments because of this program. Student outcomes and future plans to improve the program will also be discussed.

  18. Surface effects on the mechanical properties of nanoporous materials

    International Nuclear Information System (INIS)

    Lu Zixing; Zhang Cungang; Liu Qiang; Yang Zhenyu

    2011-01-01

    In this paper, surface effects on the mechanical behaviour of nanoporous materials are investigated using the theory of surface elasticity and Timoshenko beam theory based on the tetrakaidecahedron (or Kelvin) open-cell foam model. Meanwhile, the influence of surface elasticity and residual surface stress on the mechanical properties of nanoporous materials is discussed. In addition, the results derived from the theory of Euler-Bernoulli beam model are also provided for comparison. Theoretical results show that the effective Young's modulus of the nanoporous materials increases as the diameter of the strut decreases, but in contrast Poisson's ratio and the brittle collapse strength decrease with the diameter of the strut. The contribution of shear deformation to surface effects on elastic properties is more significant, while the surface effects on brittle collapse strength are not sensitive to shear deformation, and it can even be neglected. As the strut size increases, the present results can be reduced to the cases without considering surface effects, which verifies the efficiency of the present model to a certain extent.

  19. A Study of Crystalline Mechanism of Penetration Sealer Materials.

    Science.gov (United States)

    Teng, Li-Wei; Huang, Ran; Chen, Jie; Cheng, An; Hsu, Hui-Mi

    2014-01-14

    It is quite common to dispense a topping material like crystalline penetration sealer materials (CPSM) onto the surface of a plastic substance such as concrete to extend its service life span by surface protections from outside breakthrough. The CPSM can penetrate into the existing pores or possible cracks in such a way that it may form crystals to block the potential paths which provide breakthrough for any unknown materials. This study investigated the crystalline mechanism formed in the part of concrete penetrated by the CPSM. We analyzed the chemical composites, in order to identify the mechanism of CPSM and to evaluate the penetrated depth. As shown in the results, SEM observes the acicular-structured crystals filling capillary pores for mortar substrate of the internal microstructure beneath the concrete surface; meanwhile, XRD and FT-IR showed the main hydration products of CPSM to be C-S-H gel and CaCO₃. Besides, MIP also shows CPSM with the ability to clog capillary pores of mortar substrate; thus, it reduces porosity, and appears to benefit in sealing pores or cracks. The depth of CPSM penetration capability indicated by TGA shows 0-10 mm of sealer layer beneath the concrete surface.

  20. A Study of Crystalline Mechanism of Penetration Sealer Materials

    Directory of Open Access Journals (Sweden)

    Li-Wei Teng

    2014-01-01

    Full Text Available It is quite common to dispense a topping material like crystalline penetration sealer materials (CPSM onto the surface of a plastic substance such as concrete to extend its service life span by surface protections from outside breakthrough. The CPSM can penetrate into the existing pores or possible cracks in such a way that it may form crystals to block the potential paths which provide breakthrough for any unknown materials. This study investigated the crystalline mechanism formed in the part of concrete penetrated by the CPSM. We analyzed the chemical composites, in order to identify the mechanism of CPSM and to evaluate the penetrated depth. As shown in the results, SEM observes the acicular-structured crystals filling capillary pores for mortar substrate of the internal microstructure beneath the concrete surface; meanwhile, XRD and FT-IR showed the main hydration products of CPSM to be C-S-H gel and CaCO3. Besides, MIP also shows CPSM with the ability to clog capillary pores of mortar substrate; thus, it reduces porosity, and appears to benefit in sealing pores or cracks. The depth of CPSM penetration capability indicated by TGA shows 0–10 mm of sealer layer beneath the concrete surface.

  1. Modeling the Mechanical Behavior of Ceramic Matrix Composite Materials

    Science.gov (United States)

    Jordan, William

    1998-01-01

    Ceramic matrix composites are ceramic materials, such as SiC, that have been reinforced by high strength fibers, such as carbon. Designers are interested in using ceramic matrix composites because they have the capability of withstanding significant loads while at relatively high temperatures (in excess of 1,000 C). Ceramic matrix composites retain the ceramic materials ability to withstand high temperatures, but also possess a much greater ductility and toughness. Their high strength and medium toughness is what makes them of so much interest to the aerospace community. This work concentrated on two different tasks. The first task was to do an extensive literature search into the mechanical behavior of ceramic matrix composite materials. This report contains the results of this task. The second task was to use this understanding to help interpret the ceramic matrix composite mechanical test results that had already been obtained by NASA. Since the specific details of these test results are subject to the International Traffic in Arms Regulations (ITAR), they are reported in a separate document (Jordan, 1997).

  2. Mechanical properties of materials with nanometer scale dimensions and microstructures

    Energy Technology Data Exchange (ETDEWEB)

    Nix, William D. [Stanford Univ., CA (United States)

    2015-08-05

    The three-year grant for which this final report is required extends from 2011 to 2015, including a one-year, no-cost extension. But this is just the latest in a long series of grants from the Division of Materials Sciences of DOE and its predecessor offices and agencies. These include contracts or grants from: the Metallurgy Branch of the U.S. Atomic Energy Commission (from the late 1960s to the mid-1970s), the Materials Science Program of the U.S. Energy Research and Development Administration (from the mid- to late- 1970s), and the Division of Materials Science of the Office of Basic Energy Sciences of the U.S. Department of Energy (from the early 1980s to the present time). Taken all together, these offices have provided nearly continuous support for our research for nearly 50 years. As we have said on many occasions, this research support has been the best we have ever had, by far. As we look back on the nearly five decades of support from the Division of Materials Sciences and the predecessor offices, we find that the continuity of support that we have enjoyed has allowed us to be most productive and terms of papers published, doctoral students graduated and influence on the field of materials science. This report will, of course, cover the three-year period of the present grant, in summary form, but will also make reference to the output that resulted from support of previous grants from the Division of Materials Sciences and its predecessor offices.

  3. The Mechanical Behaviors of Various Dental Implant Materials under Fatigue

    Directory of Open Access Journals (Sweden)

    Fatma Bayata

    2018-01-01

    Full Text Available The selection of materials has a considerable role on long-term stability of implants. The materials having high resistance to fatigue are required for dental implant applications since these implants are subjected to cyclic loads during chewing. This study evaluates the performance of different types of materials (AISI 316L stainless steel, alumina and its porous state, CoCr alloys, yttrium-stabilized zirconia (YSZ, zirconia-toughened alumina (ZTA, and cp Ti with the nanotubular TiO2 surface by finite element analysis (FEA under real cyclic biting loads and researches the optimum material for implant applications. For the analysis, the implant design generated by our group was utilized. The mechanical behavior and the life of the implant under biting loads were estimated based on the material and surface properties. According to the condition based on ISO 14801, the FEA results showed that the equivalent von Mises stress values were in the range of 226.95 MPa and 239.05 MPa. The penetration analysis was also performed, and the calculated penetration of the models onto the bone structure ranged between 0.0037389 mm and 0.013626 mm. L-605 CoCr alloy-assigned implant model showed the least penetration, while cp Ti with the nanotubular TiO2 surface led to the most one. However, the difference was about 0.01 mm, and it may not be evaluated as a distinct difference. As the final numerical evaluation item, the fatigue life was executed, and the results were achieved in the range of 4 × 105 and 1 × 109 cycles. These results indicated that different materials showed good performance for each evaluation component, but considering the overall mechanical performance and the treatment process (implant adsorption by means of surface properties, cp Ti with the nanotubular TiO2 surface material was evaluated as the suitable one, and it may also be implied that it displayed enough performance in the designed dental implant model.

  4. Overview of the U.S. Fusion Materials Sciences Program

    International Nuclear Information System (INIS)

    Zinkle, Steven J.

    2005-01-01

    Highlights of recent U.S. fusion materials research activities are summarized, including multiscale materials modeling and experimental results. Recent first principles atomistic calculations on vanadium and iron-helium have found that previous interatomic potentials incorrectly predict several important point defect properties. Molecular dynamics simulations of displacement cascades are now approaching energies equivalent to 14 MeV fusion neutrons. Considerable effort is being devoted to understanding the fundamental mechanisms of low temperature radiation hardening and embrittlement. Work is also in progress to determine the allowable temperature and dose operating regimes for candidate reduced activation structural materials (including transmutant helium effects). New compositions of reduced activation steels and vanadium alloys with potential for significantly improved properties are being investigated. Due to recent improvements in SiC/SiC ceramic composites, engineering-relevant mechanical property tests are being introduced to replace historical qualitative screening tests. Materials research in support of the ITER burning plasma physics machine is briefly described

  5. Development and mechanical properties of structural materials from lunar simulants

    Science.gov (United States)

    Desai, Chandra S.; Girdner, K.; Saadatmanesh, H.; Allen, T.

    1991-01-01

    Development of the technologies for manufacture of structural and construction materials on the Moon, utilizing local lunar soil (regolith), without the use of water, is an important element for habitats and explorations in space. Here, it is vital that the mechanical behavior such as strength and flexural properties, fracture toughness, ductility and deformation characteristics be defined toward establishment of the ranges of engineering applications of the materials developed. The objective is to describe the research results in two areas for the above goal: (1) liquefaction of lunar simulant (at about 100 C) with different additives (fibers, powders, etc.); and (2) development and use of a new triaxial test device in which lunar simulants are first compressed under cycles of loading, and then tested with different vacuums and initial confining or in situ stress.

  6. Enclosed mechanical seal face design for brittle materials copyright

    International Nuclear Information System (INIS)

    Marsi, J.A.

    1994-01-01

    Metal carbides are widely used as seal face material due to their hardness and wear resistance. Silicon carbide (SiC) has excellent performance as a seal face material, but it is relatively brittle and may break due to accidental overloads outside the boundary of normal operating conditions. In mechanical seals for nuclear primary coolant pumps, the shattered SiC pieces can get into the reactor system and cause serious damage. The conventional method of containing an SiC seal face is to shrink-fit it in a holder, which may lead the seal designer to contend with unwanted seal face deflections. This paper presents a successful, tested design which does not rely on shrink-fits. 5 refs., 9 figs., 4 tabs

  7. Mechanical Resonators for Material Characterization: Sensor Development and Applications

    DEFF Research Database (Denmark)

    Casci Ceccacci, Andrea; Bosco, Filippo Giacomo

    The goals of this PhD project were to provide new approaches and developing new systems for material characterization, based on micro and nanomechanical sensors. Common issues that have shown to hinder large-scale integration of sensing techniques based on a micromechanical sensor are the readout......-co-Glycolic Acid (PLGA), which is of high relevance in the biomedical research field. A second version of the system is currently under development, and it aims to increase the throughput of the system allowing to read out multiple microbridge arrays. For material characterization, spectroscopy analysis is often...... considered a benchmark technology. Conventional infrared spectroscopy approaches commonly require milligram amount of sample. Considering the frame of reference given by the overall aim of the project, mechanical sensors can be exploited to provide a unique tool for performing spectroscopy on a limited...

  8. Development and mechanical properties of structural materials from lunar simulant

    Science.gov (United States)

    Desai, Chandra S.

    1991-01-01

    Development of versatile engineering materials from locally available materials in space is an important step toward establishment of outposts such as on the moon and Mars. Here development of the technologies for manufacture of structural and construction materials on the moon, utilizing local lunar soil (regolith), without the use of water, is an important element for habitats and explorations in space. It is also vital that the mechanical behavior such as strength and flexural properties, fracture toughness, ductility, and deformation characteristics are defined toward establishment of the ranges of engineering applications of the materials developed. The objectives include two areas: (1) thermal liquefaction of lunar simulant (at about 1100 C) with different additives (fibers, powders, etc.); and (2) development and use of a traxial test device in which lunar simulants are first compacted under cycles of loading, and then tested with different vacuums and initial confining or insitu stress. The second area was described in previous progress reports and publications; since the presently available device allows vacuum levels up to only 10(exp -4) torr, it is recommended that a vacuum pump that can allow higher levels of vacuum is acquired.

  9. Development and mechanical properties of construction materials from lunar simulant

    Science.gov (United States)

    Desai, Chandra S.

    1992-01-01

    Development of versatile engineering materials from locally available materials in space is an important step toward the establishment of outposts on the Moon and Mars. Development of the technologies for manufacture of structural and construction materials on the Moon, utilizing local lunar soil (regolith), without the use of water, is an important element for habitats and explorations in space. It is also vital that the mechanical behavior such as strength and tensile, flexural properties, fracture toughness, ductility, and deformation characteristics are defined toward establishment of the ranges of engineering applications of the materials developed. The objectives include two areas: (1) thermal 'liquefaction' of lunar simulant (at about 1100 C) with different additives (fibers, powders, etc.), and (2) development and use of a new triaxial test device in which lunar simulants are first compacted under cycles of loading, and then tested with different vacuums and initial confining or in situ stress. Details of the development of intermediate ceramic composites (ICC) and testing for their flexural and compression characteristics were described in various reports and papers. The subject of behavior of compacted simulant under vacuum was described in previous progress reports and publications; since the presently available device allows vacuum levels up to only 10(exp -4) torr, it is recommended that a vacuum pump that can allow higher levels of vacuum be utilized for further investigation.

  10. The interface between metallurgy and mechanics in material performance

    Directory of Open Access Journals (Sweden)

    M. Newby

    2010-10-01

    Full Text Available This paper considers an important topic, and one that is often poorly understood or misinterpreted, but which is a determining factor in many aspects of the service performance of metals (and other materials. Engineering components and structures must, of necessity, provide a bridge between the macroscopic, homogeneous and generally continuum aspects of applied load and displacement, and the microscopic, heterogeneous and often non-continuum reality of material structure and behaviour. This bridge can take the form of a genuine interface between material and environment, e.g. at a surface, or can be a virtual one where the differing philosophies of design have to be merged. The interface has particular importance in circumstances where environmental influences have a key role in determining performance characteristics (e.g. creep, environmentally-assisted cracking, or corrosion, where performance is dominated by fatigue or fracture, where welding is used to join components, or where tribology plays a role. The paper focuses on the problems associated with cracking and uses case study examples drawn from engineering practice to illustrate the role of metallurgical factors in mechanical performance of materials.

  11. Mechanically Strong Lightweight Materials for Aerospace Applications (x-aerogels)

    Science.gov (United States)

    Leventis, Nicholas

    2005-01-01

    The X-Aerogel is a new NASA-developed strong lightweight material made by reacting the mesoporous surfaces of 3-D networks of inorganic nanoparticles with polymeric crosslinkers. Since the relative amount of the crosslinker and the backbone are comparable, X-Aerogels can be viewed either as aerogels modified by templated accumulation of polymer on the skeletal nanoparticles, or as nanoporous polymers made by templated casting of polymeric precursors on a nanostructured framework. The most striking feature of X-Aerogels is that for a nominal 3-fold increase in density (still a ultralightweight material), the mechanical strength can be up to 300 times higher than the strength of the underlying native aerogel. Thus, X-Aerogels combine a multiple of the specific compressive strength of steel, with the thermal conductivity of styrofoam. XAerogels have been demonstrated with several polymers such as polyurethanes/polyureas, epoxies and polyolefins, while crosslinking of approximately 35 different oxide aerogels yields a wide variety of dimensionally stable, porous lightweight materials with interesting structural, magnetic and optical properties. X-Aerogels are evaluated for cryogenic rocket fuel storage tanks and for Advanced EVA suits, where they will play the dual role of the thermal insulator/structural material. Along the same lines, major impact is also expected by the use of X-Aerogels in structural components/thermal protection for small satellites, spacecrafts, planetary vehicles and habitats.

  12. Martian gullies: possible formation mechanism by dry granular material..

    Science.gov (United States)

    Cedillo-Flores, Y.; Durand-Manterola, H. J.

    section Some of the geomorphological features in Mars are the gullies Some theories developed tried explain its origin either by liquid water liquid carbon dioxide or flows of dry granular material We made a comparative analysis of the Martian gullies with the terrestrial ones We propose that the mechanism of formation of the gullies is as follows In winter CO 2 snow mixed with sand falls in the terrain In spring the CO 2 snow sublimate and gaseous CO 2 make fluid the sand which flows like liquid eroding the terrain and forming the gullies By experimental work with dry granular material we simulated the development of the Martian gullies injecting air in the granular material section We present the characteristics of some terrestrial gullies forms at cold environment sited at Nevado de Toluca Volcano near Toluca City M e xico We compare them with Martian gullies choose from four different areas to target goal recognize or to distinguish to identify possible processes evolved in its formation Also we measured the lengths of those Martian gullies and the range was from 24 m to 1775 meters Finally we present results of our experimental work at laboratory with dry granular material

  13. The history of theoretical, material and computational mechanics mathematics meets mechanics and engineering

    CERN Document Server

    2014-01-01

    This collection of 23 articles is the output of lectures in special sessions on “The History of Theoretical, Material and Computational Mechanics” within the yearly conferences of the GAMM in the years 2010 in Karlsruhe, Germany, 2011 in Graz, Austria, and in 2012 in Darmstadt, Germany; GAMM is the “Association for Applied Mathematics and Mechanics”, founded in 1922 by Ludwig Prandtl and Richard von Mises. The contributions in this volume discuss different aspects of mechanics. They are related to solid and fluid mechanics in general and to specific problems in these areas including the development of numerical solution techniques. In the first part the origins and developments of conservation principles in mechanics and related variational methods are treated together with challenging applications from the 17th to the 20th century. Part II treats general and more specific aspects of material theories of deforming solid continua and porous soils. and Part III presents important theoretical and enginee...

  14. Execution of Educational Mechanical Production Programs for School Children

    Science.gov (United States)

    Itoh, Nobuhide; Itoh, Goroh; Shibata, Takayuki

    The authors are conducting experience-based engineering educational programs for elementary and junior high school students with the aim to provide a chance for them to experience mechanical production. As part of this endeavor, we planned and conducted a program called “Fabrication of Original Magnet Plates by Casting” for elementary school students. This program included a course for leading nature laws and logical thinking method. Prior to the program, a preliminary program was applied to school teachers to get comments and to modify for the program accordingly. The children responded excellently to the production process which realizes their ideas, but it was found that the course on natural laws and logical methods need to be improved to draw their interest and attention. We will continue to plan more effective programs, deepening ties with the local community.

  15. European Fusion Materials Research Program - Recent Results and Future Strategy

    International Nuclear Information System (INIS)

    Diegele, E.; Andreani, R.; Laesser, R.; Schaaf, B. van der

    2005-01-01

    The paper reviews the objectives and the status of the current EU long-term materials program. It highlights recent results, discusses some of the key issues and major existing problems to be resolved and presents an outlook on the R and D planned for the next few years. The main objectives of the Materials Development program are the development and qualification of reduced activation structural materials for the Test Blanket Modules (TBMs) in ITER and of low activation structural materials resistant to high fluence neutron irradiation for in-vessel components such as breeding blanket, divertor and first wall in DEMO. The EU strategy assumes: (i) ITER operation starting in 2015 with DEMO relevant Test Blanket Modules to be installed from day one of operation, (ii) IFMIF operation in 2017 and (iii) DEMO final design activities in 2022 to 2025. The EU candidate structural material EUROFER for TBMs has to be fully code qualified for licensing well before 2015. In parallel, research on materials for operation at higher temperatures is conducted following a logical sequence, by supplementing EUROFER with the oxide dispersion strengthened ferritic steels and, thereafter, with fibre-reinforced Silicon Carbide (SiC f /SiC). Complementary, tungsten alloys are developed as structural material for high temperature applications such as gas-cooled divertors

  16. Salt repository sealing materials development program: 5-year work plan

    International Nuclear Information System (INIS)

    Myers, L.B.

    1986-06-01

    This plan covers 5 years (fiscal years 1986 through 1990) of work in the repository sealing materials program to support design decisions and licensing activities for a salt repository. The plan covers a development activity, not a research activity. There are firm deliverables as the end points of each part of the work. The major deliverables are: development plans for code development and materials testing; seal system components models; seal system performance specifications; seal materials specifications; and seal materials properties ''handbook.'' The work described in this plan is divided into three general tasks as follows: mathematical modeling; materials studies (salt, cementitious materials, and earthen materials); and large-scale testing. Each of the sections presents an overview, status, planned activities, and summary of program milestones. This plan will be the starting point for preparing the development plans described above, but is subject to change if preparation of the work plan indicates that a different approach or sequence is preferable to achieve the ultimate goal, i.e., support of design and licensing

  17. Mechanism for subgap optical conductivity in honeycomb Kitaev materials

    Science.gov (United States)

    Bolens, Adrien; Katsura, Hosho; Ogata, Masao; Miyashita, Seiji

    2018-04-01

    Motivated by recent terahertz absorption measurements in α -RuCl3 , we develop a theory for the electromagnetic absorption of materials described by the Kitaev model on the honeycomb lattice. We derive a mechanism for the polarization operator at second order in the nearest-neighbor hopping Hamiltonian. Using the exact results of the Kitaev honeycomb model, we then calculate the polarization dynamical correlation function corresponding to electric dipole transitions in addition to the spin dynamical correlation function corresponding to magnetic dipole transitions.

  18. Mississippi Curriculum Framework for Automotive Mechanics (Program CIP: 47.0604--Auto/Automotive Mechanic/Tech). Secondary Programs.

    Science.gov (United States)

    Mississippi Research and Curriculum Unit for Vocational and Technical Education, State College.

    This document, which reflects Mississippi's statutory requirement that instructional programs be based on core curricula and performance-based assessment, contains outlines of the instructional units required in local instructional management plans and daily lesson plans for automotive mechanics I and II. Presented first are a program description…

  19. Quality assurance program description for shipping packages of radioactive material

    International Nuclear Information System (INIS)

    1978-01-01

    This quality assurance plan describes the quality assurance program at the Pacific Northwest Laboratory (PNL), for shipping packages of radioactive material. The purpose of this report is to describe how PNL will comply with the Code of Federal Regulations, Title 10, Part 71, Appendix E. In compliance with the instructions from the Nuclear Regulatory Commission (NRC), the 18 criteria from Appendix E are covered

  20. DOE materials program supporting immobilization of radioactive wastes

    International Nuclear Information System (INIS)

    Oertel, G.K.; Scheib, W.S. Jr.

    1979-01-01

    A summary is presented of the DOE program for developing waste-form criteria, immobilization processes, and generation and evaluation of performance characterization data. Interrelationships are discussed among repository design, materials requirements, immobilization process definition, quality assurance, and risk analysis as part of the National Environmental Policy Act and regulatory processes

  1. 3D Printing of Materials with Tunable Failure via Bioinspired Mechanical Gradients.

    Science.gov (United States)

    Kokkinis, Dimitri; Bouville, Florian; Studart, André R

    2018-05-01

    Mechanical gradients are useful to reduce strain mismatches in heterogeneous materials and thus prevent premature failure of devices in a wide range of applications. While complex graded designs are a hallmark of biological materials, gradients in manmade materials are often limited to 1D profiles due to the lack of adequate fabrication tools. Here, a multimaterial 3D-printing platform is developed to fabricate elastomer gradients spanning three orders of magnitude in elastic modulus and used to investigate the role of various bioinspired gradient designs on the local and global mechanical behavior of synthetic materials. The digital image correlation data and finite element modeling indicate that gradients can be effectively used to manipulate the stress state and thus circumvent the weakening effect of defect-rich interfaces or program the failure behavior of heterogeneous materials. Implementing this concept in materials with bioinspired designs can potentially lead to defect-tolerant structures and to materials whose tunable failure facilitates repair of biomedical implants, stretchable electronics, or soft robotics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Next Generation Nuclear Plant Materials Research and Development Program Plan

    International Nuclear Information System (INIS)

    G.O. Hayner; R.L. Bratton; R.N. Wright

    2005-01-01

    The U.S Department of Energy (DOE) has selected the Very High Temperature Reactor (VHTR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production without greenhouse gas emissions. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed, thermal neutron spectrum reactor that will produce electricity and hydrogen in a state-of-the-art thermodynamically efficient manner. The NGNP will use very high burn-up, low-enriched uranium, TRISO-coated fuel and have a projected plant design service life of 60 years. The VHTR concept is considered to be the nearest-term reactor design that has the capability to efficiently produce hydrogen. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Project is envisioned to demonstrate the following: (1) A full-scale prototype VHTR by about 2021; (2) High-temperature Brayton Cycle electric power production at full scale with a focus on economic performance; (3) Nuclear-assisted production of hydrogen (with about 10% of the heat) with a focus on economic performance; and (4) By test, the exceptional safety capabilities of the advanced gas-cooled reactors. Further, the NGNP program will: (1) Obtain a Nuclear Regulatory Commission (NRC) License to construct and operate the NGNP, this process will provide a basis for future performance based, risk-informed licensing; and (2) Support the development, testing, and prototyping of hydrogen infrastructures. The NGNP Materials Research and Development (R and D) Program is responsible for performing R and D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. The NGNP Materials R and D Program includes the following elements: (1) Developing a specific approach, program plan and other project management

  3. Enhancing materials management programs in nuclear power plants

    International Nuclear Information System (INIS)

    Hassaballa, M.M.; Malak, S.M.

    1992-01-01

    Materials management programs for the nuclear utilities in the United States are continually being affected, concurrent with the gradual disappearance of qualified component and replacement parts vendors by regulatory concerns about procurement and materials management. In addition, current economic and competitive pressures are forcing utilities to seek avenues for reducing procurement costs for safety-related items. In response to these concerns, initiatives have been undertaken and engineering guidelines have been developed by the nuclear power industry-sponsored organizations, such as the Electric Power Research Institute and the Nuclear Management Resources Council. It is our experience that successful materials management programs require a multitude of engineering disciplines and experience and are composed of three major elements: strategic procurement plan, parts classification and procurement data base, and enhancement tools. This paper provides a brief description of each of the three elements

  4. Next Generation Nuclear Plant Materials Research and Development Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    G.O. Hayner; R.L. Bratton; R.N. Wright

    2005-09-01

    The U.S Department of Energy (DOE) has selected the Very High Temperature Reactor (VHTR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production without greenhouse gas emissions. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed, thermal neutron spectrum reactor that will produce electricity and hydrogen in a state-of-the-art thermodynamically efficient manner. The NGNP will use very high burn-up, low-enriched uranium, TRISO-coated fuel and have a projected plant design service life of 60 years. The VHTR concept is considered to be the nearest-term reactor design that has the capability to efficiently produce hydrogen. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Project is envisioned to demonstrate the following: (1) A full-scale prototype VHTR by about 2021; (2) High-temperature Brayton Cycle electric power production at full scale with a focus on economic performance; (3) Nuclear-assisted production of hydrogen (with about 10% of the heat) with a focus on economic performance; and (4) By test, the exceptional safety capabilities of the advanced gas-cooled reactors. Further, the NGNP program will: (1) Obtain a Nuclear Regulatory Commission (NRC) License to construct and operate the NGNP, this process will provide a basis for future performance based, risk-informed licensing; and (2) Support the development, testing, and prototyping of hydrogen infrastructures. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. The NGNP Materials R&D Program includes the following elements: (1) Developing a specific approach, program plan and other project management tools for

  5. Segmented fuel irradiation program: investigation on advanced materials

    International Nuclear Information System (INIS)

    Uchida, H.; Goto, K.; Sabate, R.; Abeta, S.; Baba, T.; Matias, E. de; Alonso, J.

    1999-01-01

    The Segmented Fuel Irradiation Program, started in 1991, is a collaboration between the Japanese organisations Nuclear Power Engineering Corporation (NUPEC), the Kansai Electric Power Co., Inc. (KEPCO) representing other Japanese utilities, and Mitsubishi Heavy Industries, Ltd. (MHI); and the Spanish Organisations Empresa Nacional de Electricidad, S.A. (ENDESA) representing A.N. Vandellos 2, and Empresa Nacional Uranio, S.A. (ENUSA); with the collaboration of Westinghouse. The objective of the Program is to make substantial contribution to the development of advanced cladding and fuel materials for better performance at high burn-up and under operational power transients. For this Program, segmented fuel rods were selected as the most appropriate vehicle to accomplish the aforementioned objective. Thus, a large number of fuel and cladding combinations are provided while minimising the total amount of new material, at the same time, facilitating an eventual irradiation extension in a test reactor. The Program consists of three major phases: phase I: design, licensing, fabrication and characterisation of the assemblies carrying the segmented rods (1991 - 1994); phase II: base irradiation of the assemblies at Vandellos 2 NPP, and on-site examination at the end of four cycles (1994-1999). Phase III: ramp testing at the Studsvik facilities and hot cell PIE (1996-2001). The main fuel design features whose effects on fuel behaviour are being analysed are: alloy composition (MDA and ZIRLO vs. Zircaloy-4); tubing texture; pellet grain size. The Program is progressing satisfactorily as planned. The base irradiation is completed in the first quarter of 1999, and so far, tests and inspections already carried out are providing useful information on the behaviour of the new materials. Also, the Program is delivering a well characterized fuel material, irradiated in a commercial reactor, which can be further used in other fuel behaviour experiments. The paper presents the main

  6. Advanced Industrial Materials (AIM) program. Annual progress report. FY 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    The Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven `Vision Industries` that use about 80% of industrial energy and generated about 90% of industrial wastes. These are: aluminium; chemical; forest products; glass; metal casting; refineries; and steel. OIT is working with these industries, through appropriate organizations, to develop Visions of the desired condition of each industry some 20 or 25 years in the future and then to prepare Road Maps and Implementation Plans to enable them to reach their goals. The mission of AIM has, therefore, changed to `Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.` Though AIM remains essentially a National Laboratory Program, it is necessary that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains healthy and productive, thanks to the superb investigators and Laboratory Program Managers. Separate abstracts have been indexed into the energy database for articles from this report.

  7. Multiyear Program Plan for the High Temperature Materials Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Arvid E. Pasto

    2000-03-17

    Recently, the U.S. Department of Energy's (DOE) Office of Heavy Vehicle Technologies (OHVT) prepared a Technology Roadmap describing the challenges facing development of higher fuel efficiency, less polluting sport utility vehicles, vans, and commercial trucks. Based on this roadmap, a multiyear program plan (MYPP) was also developed, in which approaches to solving the numerous challenges are enumerated. Additional planning has been performed by DOE and national laboratory staff, on approaches to solving the numerous challenges faced by heavy vehicle system improvements. Workshops and planning documents have been developed concerning advanced aerodynamics, frictional and other parasitic losses, and thermal management. Similarly, the Heavy Vehicle Propulsion Materials Program has developed its own multiyear program plan. The High Temperature Materials Laboratory, a major user facility sponsored by OHVT, has now developed its program plan, described herein. Information was gathered via participation in the development of OHVT's overall Technology Roadmap and MYPP, through personal contacts within the materials-user community, and from attendance at conferences and expositions. Major materials issues for the heavy vehicle industry currently center on trying to increase efficiency of (diesel) engines while at the same time reducing emissions (particularly NO{sub x} and particulates). These requirements dictate the use of increasingly stronger, higher-temperature capable and more corrosion-resistant materials of construction, as well as advanced catalysts, particulate traps, and other pollution-control devices. Exhaust gas recirculation (EGR) is a technique which will certainly be applied to diesel engines in the near future, and its use represents a formidable challenge, as will be described later. Energy-efficient, low cost materials processing methods and surface treatments to improve wear, fracture, and corrosion resistance are also required.

  8. Multiyear Program Plan for the High Temperature Materials Laboratory; FINAL

    International Nuclear Information System (INIS)

    Arvid E. Pasto

    2000-01-01

    Recently, the U.S. Department of Energy's (DOE) Office of Heavy Vehicle Technologies (OHVT) prepared a Technology Roadmap describing the challenges facing development of higher fuel efficiency, less polluting sport utility vehicles, vans, and commercial trucks. Based on this roadmap, a multiyear program plan (MYPP) was also developed, in which approaches to solving the numerous challenges are enumerated. Additional planning has been performed by DOE and national laboratory staff, on approaches to solving the numerous challenges faced by heavy vehicle system improvements. Workshops and planning documents have been developed concerning advanced aerodynamics, frictional and other parasitic losses, and thermal management. Similarly, the Heavy Vehicle Propulsion Materials Program has developed its own multiyear program plan. The High Temperature Materials Laboratory, a major user facility sponsored by OHVT, has now developed its program plan, described herein. Information was gathered via participation in the development of OHVT's overall Technology Roadmap and MYPP, through personal contacts within the materials-user community, and from attendance at conferences and expositions. Major materials issues for the heavy vehicle industry currently center on trying to increase efficiency of (diesel) engines while at the same time reducing emissions (particularly NO(sub x) and particulates). These requirements dictate the use of increasingly stronger, higher-temperature capable and more corrosion-resistant materials of construction, as well as advanced catalysts, particulate traps, and other pollution-control devices. Exhaust gas recirculation (EGR) is a technique which will certainly be applied to diesel engines in the near future, and its use represents a formidable challenge, as will be described later. Energy-efficient, low cost materials processing methods and surface treatments to improve wear, fracture, and corrosion resistance are also required

  9. MAPLIB, Thermodynamics Materials Property Generator for FORTRAN Program

    International Nuclear Information System (INIS)

    Schumann, U.; Zimmerer, W. and others

    1978-01-01

    1 - Nature of physical problem solved: MAPLIB is a program system which is able to incorporate the values of the properties of any material in a form suitable for use in other computer programs. The data are implemented in FORTRAN functions. A utility program is provided to assist in library management. 2 - Method of solution: MAPLIB consists of the following parts: 1) Conventions for the data format. 2) Some integrated data. 3) A data access system (FORTRAN subroutine). 4) An utility program for updating and documentation of the actual library content. The central part is a set of FORTRAN functions, e.g. WL H2O v(t,p) (heat conduction of water vapor as a function of temperature and pressure), which compute the required data and which can be called by the user program. The data content of MAPLIB has been delivered by many persons. There was no systematic evaluation of the material. It is the responsibility of every user to check the data for physical accuracy. MAPLIB only serves as a library system for manipulation and storing of such data. 3 - Restrictions on the complexity of the problem: a) See responsibility as explained above. b) Up to 1000 data functions could be implemented. c) If too many data functions are included in MAPLIB, the storage requirements become excessive for application in users programs

  10. Versatile equipment for mechanical testing of active materials

    International Nuclear Information System (INIS)

    Bertsch, Johannes; Heimgartner, Peter

    2005-01-01

    At the Paul Scherrer Institute (PSI) 3 different project groups presently perform aging research on active materials. The research fields are fusion, high neutron flux targets and LWR relevant components. Up to now mechanical testing has been performed with small, low dose rate samples behind local shielding, not appropriate for highly activated material. To overcome this situation, a cell concept for active mechanical testing was elaborated and has been erected in PSI's Hotlab. It consists of 4 shielded cells. 3 connected cells are versatile and independently operable for highly beta/gamma active samples. One cell is an alpha/beta/gamma-box which will be realized in a second phase. This paper presents the versatility especially of the beta/gamma-cells: The different user groups perform experiments in these cells, whereas different machines can be placed into the cells. As consequence of the need of heavily shielded cell doors, a special strengthening and levelling of the floor has been required. In all cells the relevant media are installed. Besides the performance of the cells, the project progress as the difficulties and their solutions are described. (Author)

  11. Development and demonstration program for dynamic nuclear materials control

    International Nuclear Information System (INIS)

    Augustson, R.H.; Baron, N.; Ford, R.F.; Ford, W.; Hagen, J.; Li, T.K.; Marshall, R.S.; Reams, V.S.; Severe, W.R.; Shirk, D.G.

    1978-01-01

    A significant portion of the Los Alamos Scientific Laboratory Safeguards Program is directed toward the development and demonstration of dynamic nuclear materials control. The building chosen for the demonstration system is the new Plutonium Processing Facility in Los Alamos, which houses such operations as metal-to-oxide conversion, fuel pellet fabrication, and scrap recovery. A DYnamic MAterials Control (DYMAC) system is currently being installed in the facility as an integral part of the processing operation. DYMAC is structured around interlocking unit-process accounting areas. It relies heavily on nondestructive assay measurements made in the process line to draw dynamic material balances in near real time. In conjunction with the nondestructive assay instrumentation, process operators use interactive terminals to transmit additional accounting and process information to a dedicated computer. The computer verifies and organizes the incoming data, immediately updates the inventory records, monitors material in transit using elapsed time, and alerts the Nuclear Materials Officer in the event that material balances exceed the predetermined action limits. DYMAC is part of the United States safeguards system under control of the facility operator. Because of its advanced features, the system will present a new set of inspection conditions to the IAEA, whose response is the subject of a study being sponsored by the US-IAEA Technical Assistance Program. The central issue is how the IAEA can use the increased capabilities of such a system and still maintain independent verification

  12. Radiation damage calculations for the APT materials test program

    International Nuclear Information System (INIS)

    Corzine, R.K.; Wechsler, M.S.; Dudziak, D.J.; Ferguson, P.D.; James, M.R.

    1999-01-01

    A materials irradiation was performed at the Los Alamos Neutron Science Center (LANSCE) in the fall of 1996 and spring of 1997 in support of the Accelerator Production of Tritium (APT) program. Testing of the irradiated materials is underway. In the proposed APT design, materials in the target and blanket are to be exposed to protons and neutrons over a wide range of energies. The irradiation and testing program was undertaken to enlarge the very limited direct knowledge presently available of the effects of medium-energy protons (∼1 GeV) on the properties of engineering materials. APT candidate materials were placed in or near the LANSCE accelerator 800-MeV, 1-mA proton beam and received roughly the same proton current density in the center of the beam as would be the case for the APT facility. As a result, the proton fluences achieved in the irradiation were expected to approach the APT prototypic full-power-year values. To predict accurately the performance of materials in APT, radiation damage parameters for the materials experiment must be determined. By modeling the experiment, calculations for atomic displacement, helium and hydrogen cross sections and for proton and neutron fluences were done for representative samples in the 17A, 18A, and 18C areas. The LAHET code system (LCS) was used to model the irradiation program, LAHET 2.82 within LCS transports protons > 1 MeV, and neutrons >20 MeV. A modified version of MCNP for use in LCS, HMCNP 4A, was employed to tally neutrons of energies <20 MeV

  13. Fundamental radiation effects studies in the fusion materials program

    International Nuclear Information System (INIS)

    Doran, D.G.

    1982-01-01

    Fundamental radiation effects studies in the US Fusion Materials Program generally fall under the aegis of the Damage Analysis and Fundamental Studies (DAFS) Program. In a narrow sense, the problem addressed by the DAFS program is the prediction of radiation effects in fusion devices using data obtained in non-representative environments. From the onset, the program has had near-term and long-term components. The premise for the latter is that there will be large economic penalties for uncertainties in predictive capability. Fusion devices are expected to be large and complex and unanticipated maintenance will be costly. It is important that predictions are based on a maximum of understanding and a minimum of empiricism. Gaining this understanding is the thrust of the long-term component. (orig.)

  14. Physical and mechanical properties of degraded waste surrogate material

    International Nuclear Information System (INIS)

    Hansen, F.D.; Mellegard, K.D.

    1998-03-01

    This paper discusses rock mechanics testing of surrogate materials to provide failure criteria for compacted, degraded nuclear waste. This daunting proposition was approached by first assembling all known parameters such as the initial waste inventory and rock mechanics response of the underground setting after the waste is stored. Conservative assumptions allowing for extensive degradation processes helped quantify the lowest possible strength conditions of the future state of the waste. In the larger conceptual setting, computations involve degraded waste behavior in transient pressure gradients as gas exits the waste horizon into a wellbore. Therefore, a defensible evaluation of tensile strength is paramount for successful analyses and intentionally provided maximal failed volumes. The very conservative approach assumes rampant degradation to define waste surrogate composition. Specimens prepared from derivative degradation product were consolidated into simple geometries for rock mechanics testing. Tensile strength thus derived helped convince a skeptical peer review panel that drilling into the Waste Isolation Pilot Plant (WIPP) would not likely expel appreciable solids via the drill string

  15. Materials balance area Custodian Performance Evaluation Program at PNL

    International Nuclear Information System (INIS)

    Dickman, D.A.

    1991-07-01

    The material balance area (MBA) custodian has primary responsibility for control and accountability of nuclear material within an MBA. In this role, the custodian operates as an extension of the facility material control and accountability (MC ampersand A) organization. To effectively meet administrative requirements and protection needs, the custodian must be fully trained in all aspects of MC ampersand A related to the MBA, and custodian performance must be periodically evaluated. DOE Policy requires that each facility provide for a program which assures that each facility provide for a program which assures that personnel performing MC ampersand A functions are (1) trained and/or qualified to perform their duties and responsibilities and (2) knowledgeable of requirements and procedures related to their functions. The MBA Custodian Performance Evaluation Program at PNL uses a variety of assessment techniques to meet this goal, including internal and independent MBA audits, periodic custodian testing, conduct of limited scope performance tests, daily monitoring of MC ampersand A documentation, and reviewing custodian performance during physical inventories. The data collected from these sources is analyzed and incorporated into an annual custodian performance evaluation document, given to each custodian and line management. Development of this program has resulted in significantly improved custodian performance and a marked decrease in finding and observations identified during MBA audits

  16. Advanced Industrial Materials (AIM) Program annual progress report, FY 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    The Advanced Industrial Materials (AIM) Program is a part of the Office of Industrial Technologies (OIT), Energy Efficiency and Renewable Energy, US Department of Energy (DOE). The mission of AIM is to support development and commercialization of new or improved materials to improve energy efficiency, productivity, product quality, and reduced waste in the major process industries. OIT has embarked on a fundamentally new way of working with industries--the Industries of the Future (IOF) strategy--concentrating on the major process industries that consume about 90% of the energy and generate about 90% of the waste in the industrial sector. These are the aluminum, chemical, forest products, glass, metalcasting, and steel industries. OIT has encouraged and assisted these industries in developing visions of what they will be like 20 or 30 years into the future, defining the drivers, technology needs, and barriers to realization of their visions. These visions provide a framework for development of technology roadmaps and implementation plans, some of which have been completed. The AIM Program supports IOF by conducting research and development on materials to solve problems identified in the roadmaps. This is done by National Laboratory/industry/university teams with the facilities and expertise needed to develop new and improved materials. Each project in the AIM Program has active industrial participation and support.

  17. Next Generation Nuclear Plant Materials Research and Development Program Plan, Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    G.O. Hayner; R.L. Bratton; R.E. Mizia; W.E. Windes; W.R. Corwin; T.D. Burchell; C.E. Duty; Y. Katoh; J.W. Klett; T.E. McGreevy; R.K. Nanstad; W. Ren; P.L. Rittenhouse; L.L. Snead; R.W. Swindeman; D.F. Wlson

    2007-09-01

    DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 950°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, TRISO-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Some of the general and administrative aspects of the R&D Plan include: • Expand American Society of Mechanical Engineers (ASME) Codes and American Society for Testing and Materials (ASTM) Standards in support of the NGNP Materials R&D Program. • Define and develop inspection needs and the procedures for those inspections. • Support selected university materials related R&D activities that would be of direct benefit to the NGNP Project. • Support international materials related collaboration activities through the DOE sponsored Generation IV International Forum (GIF) Materials and Components (M&C) Project Management Board (PMB). • Support document review activities through the Materials Review Committee (MRC) or other suitable forum.

  18. GCRA review and appraisal of fuel material development programs

    International Nuclear Information System (INIS)

    1980-09-01

    The Fuel material Development Program has as its principal objective and responsibility the development of a fuel that is both economical and licensable and that, at the same time, will fulfill the required performance criteria. To accomplish this, the program is broken down into the following major fuel development task areas: development of the experimental and analytical data base for selecting, qualifying, and verifying the reference fuel design; providing the data base and developing models for evaluating fuel performance under upset and accident conditions; and developing and justifying fuel fabrication specifications which are consistent with the overall fuel performance criteria and with the fuel fabrication process capabilities

  19. Health and safety information program for hazardous materials

    International Nuclear Information System (INIS)

    O'Brien, M.P.; Fallon, N.J.; Kuehner, A.V.

    1979-01-01

    The system is used as a management tool in several safety and health programs. It is used to: trace the use of hazardous materials and to determine monitoring needs; inform the occupational physician of the potential health problems associated with materials ordered by a given individual; inform the fire and rescue group of hazardous materials in a given building; provide waste disposal recommendations to the hazardous waste management group; assist the hazardous materials shipping coordinator in identifying materials which are regulated by the Department of Transportation; and guide management decisions in the area of recognizing and rectifying unsafe conditions. The information system has been expanded from a manual effort to provide a brief description of health hazards of chemicals used at the lab to a computerized health and safety information system which serves the needs of all personnel who may encounter the material in the course of their work. The system has been designed to provide information needed to control the potential problems associated with a hazardous material up to the time that it is consumed in a given operation or is sent to the waste disposal facility

  20. The waste minimization program at the Feed Materials Production Center

    International Nuclear Information System (INIS)

    Blasdel, J.E.; Crotzer, M.E.; Gardner, R.L.; Kato, T.R.; Spradlin, C.N.

    1987-01-01

    A waste minimization program is being implemented at the Feed Materials Production Center to reduce the generation of uranium-contaminated wastes and to comply with existing and forthcoming regulations. Procedures and plans are described which deal with process and non-process trash, contaminated wood and metals, used metal drums, and major process wastes such as contaminated magnesium fluoride and neutralized raffinate. Waste minimization techniques used include segregation, source reduction, volume reduction, material substitution and waste/product recycle. The importance of training, communication, and incentives is also covered. 5 refs., 11 figs

  1. Fracture mechanics based design for radioactive material transport packagings -- Historical review

    International Nuclear Information System (INIS)

    Smith, J.A.; Salzbrenner, D.; Sorenson, K.; McConnell, P.

    1998-04-01

    The use of a fracture mechanics based design for the radioactive material transport (RAM) packagings has been the subject of extensive research for more than a decade. Sandia National Laboratories (SNL) has played an important role in the research and development of the application of this technology. Ductile iron has been internationally accepted as an exemplary material for the demonstration of a fracture mechanics based method of RAM packaging design and therefore is the subject of a large portion of the research discussed in this report. SNL's extensive research and development program, funded primarily by the U. S. Department of Energy's Office of Transportation, Energy Management and Analytical Services (EM-76) and in an auxiliary capacity, the office of Civilian Radioactive Waste Management, is summarized in this document along with a summary of the research conducted at other institutions throughout the world. In addition to the research and development work, code and standards development and regulatory positions are also discussed

  2. Basic mechanisms of radiation effects on electronic materials and devices

    International Nuclear Information System (INIS)

    Winokur, P.S.

    1989-01-01

    Many defense and nuclear reactor systems require complementary metal-oxide semiconductor integrated circuits that are tolerant to high levels of radiation. This radiation can result from space, hostile environments or nuclear reactor and accelerator beam environments. In addition, many techniques used to fabricate today's complex very-large-scale integration circuits expose the circuits to ionizing radiation during the process sequence. Whatever its origin, radiation can cause significant damage to integrated-circuit materials. This damage can lead to circuit performance degradation, logic upset, and even catastrophic circuit failure. This paper provides a brief overview of the basic mechanisms for radiation damage to silicon-based integrated circuits. Primary emphasis is on the effects of total-dose ionizing radiation on metal-oxide-semiconductor (MOS) structures

  3. Advanced Researech and Technology Development fossil energy materials program: Semiannual progress report for the period ending September 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The objective of the ARandTD Fossil Energy Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. The ORNL Fossil Energy Materials Program Office compiles and issues this combined semiannual progress report from camera-ready copies submitted by each of the participating subcontractor organizations. This report of activities on the program is organized in accordance with a work breakdown structure in which projects are organized according to materials research thrust areas. These areas are (1) Structural Ceramics, (2) Alloy Development and Mechanical Properties, (3) Corrosion and Erosion of Alloys, and (4) Assessments and Technology Transfer. Individual projects are processed separately for the data bases.

  4. Fe-based composite materials with improved mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Werniewicz, Katarzyna [IFW Dresden, P.O. Box 270116, D-01171 Dresden (Germany); Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw (Poland); Kuehn, Uta; Mattern, Norbert; Eckert, Juergen; Schultz, Ludwig [IFW Dresden, P.O. Box 270116, D-01171 Dresden (Germany); Kulik, Tadeusz [Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw (Poland)

    2008-07-01

    Following a previous study by the authors two new compositions (Fe{sub 89.0}Cr{sub 5.5}Mo{sub 5.5}){sub 91}C{sub 9} and (Fe{sub 89.0}Cr{sub 5.5}Mo{sub 5.5}){sub 83}C{sub 17} have been developed with the aim of improving the ductility of Fe{sub 65.5}Cr{sub 4}Mo{sub 4}Ga{sub 4}P{sub 12}C{sub 5}B{sub 5.5} bulk metallic glass (BMG). In contrast to the alloys in that study, the recently prepared Fe-based materials are Ga-free. It was expected that the variations in the composition will lead to the changes in the phase formation and, hence, in the mechanical response of the investigated alloys. It was recognized that in-situ formed Fe-based composites show superior plasticity ({epsilon}{sub pl}{approx}37%) for the alloy with lower C content and ({epsilon}{sub pl}{approx}4%) for the alloy with higher C content compared to monolithic glass ({epsilon}{sub pl}{approx}0.2%). Furthermore, on the basis of present as well as previous investigations it has been shown that the Ga addition is beneficial for the plasticity of these Fe-based alloys. It was observed that the (Fe{sub 89.0}Cr{sub 5.5}Mo{sub 5.5}){sub 83}C{sub 17} alloy exhibits a significantly smaller fracture strain ({epsilon}{sub f}{approx}5%) compared to its Ga-containing counterpart ({epsilon}{sub f}{approx}16%). Therefore, it can be concluded that appropriate alloying additions are crucial in enhancing the mechanical properties of the complex Fe-based materials developed here.

  5. Optimal selection for shielding materials by fuzzy linear programming

    International Nuclear Information System (INIS)

    Kanai, Y.; Miura, N.; Sugasawa, S.

    1996-01-01

    An application of fuzzy linear programming methods to optimization of a radiation shield is presented. The main purpose of the present study is the choice of materials and the search of the ratio of mixture-component as the first stage of the methodology on optimum shielding design according to individual requirements of nuclear reactor, reprocessing facility, shipping cask installing spent fuel, ect. The characteristic values for the shield optimization may be considered their cost, spatial space, weight and some shielding qualities such as activation rate and total dose rate for neutron and gamma ray (includes secondary gamma ray). This new approach can reduce huge combination calculations for conventional two-valued logic approaches to representative single shielding calculation by group-wised optimization parameters determined in advance. Using the fuzzy linear programming method, possibilities for reducing radiation effects attainable in optimal compositions hydrated, lead- and boron-contained materials are investigated

  6. 78 FR 39271 - Applications for New Awards; Educational Technology, Media, and Materials Program for Individuals...

    Science.gov (United States)

    2013-07-01

    ... DEPARTMENT OF EDUCATION Applications for New Awards; Educational Technology, Media, and Materials...: Educational Technology, Media, and Materials Program for Individuals with Disabilities--Center on Technology... Description Purpose of Program: The purpose of the Educational Technology, Media, and Materials for...

  7. Mechanisms of Pyroelectricity in Three- and Two-Dimensional Materials

    Science.gov (United States)

    Liu, Jian; Pantelides, Sokrates T.

    2018-05-01

    Pyroelectricity is a very promising phenomenon in three- and two-dimensional materials, but first-principles calculations have not so far been used to elucidate the underlying mechanisms. Here we report density-functional theory (DFT) calculations based on the Born-Szigeti theory of pyroelectricity, by combining fundamental thermodynamics and the modern theory of polarization. We find satisfactory agreement with experimental data in the case of bulk benchmark materials, showing that the so-called electron-phonon renormalization, whose contribution has been traditionally viewed as negligible, is important. We predict out-of-plane pyroelectricity in the recently synthesized Janus MoSSe monolayer and in-plane pyroelectricity in the group-IV monochalcogenide GeS monolayer. It is notable that the so-called secondary pyroelectricity is found to be dominant in GeS monolayer. The present work opens a theoretical route to study the pyroelectric effect using DFT and provides a valuable tool in the search for new candidates for pyroelectric applications.

  8. Mechanical design of mussel byssus: material yield enhances attachment strength

    Science.gov (United States)

    Bell; Gosline

    1996-01-01

    The competitive dominance of mussels in the wave-swept rocky intertidal zone is in part due to their ability to maintain a secure attachment. Mussels are tethered to the substratum by a byssus composed of numerous extracellular, collagenous threads secreted by the foot. Each byssal thread has three serially arranged parts: a corrugated proximal region, a smooth distal region and an adhesive plaque. This study examines the material and structural properties of the byssal threads of three mussel species: Mytilus californianus, M. trossulus, and M. galloprovincialis. Tensile tests in general reveal similar material properties among species: the proximal region has a lower initial modulus, a lower ultimate stress and a higher ultimate strain than the distal region. The distal region also yields at a stress well below its ultimate value. In whole thread tests, the proximal region and adhesive plaque are common sites of structural failure and are closely matched in strength, while the distal region appears to be excessively strong. We propose that the high strength of the distal region is the byproduct of a material designed to yield and extend before structural failure occurs. Experimental and theoretical evidence is presented suggesting that thread yield and extensibility provide two important mechanisms for increasing the overall attachment strength of the mussel: (1) the reorientation of threads towards the direction of applied load, and (2) the 'recruitment' of more threads into tension and the consequent distribution of applied load over a larger cross-sectional area, thereby reducing the stress on each thread. This distal region yield behavior is most striking for M. californianus and may be a key to its success in extreme wave-swept environments.

  9. Mechanisms of hydrogen induced delayed cracking in hydride forming materials

    International Nuclear Information System (INIS)

    Dutton, R.; Nuttall, K.; Puls, M.P.; Simpson, L.A.

    1977-01-01

    Mechanisms which have been formulated to describe delayed hydrogen cracking in hydride-forming metals are reviewed and discussed. Particular emphasis is placed on the commercial alloy Zr--2.5% Nb (Cb) which is extensively used in nuclear reactor core components. A quantitative model for hydrogen cracking in this material is presented and compared with available experimental data. The kinetics of crack propagation are controlled by the growth of hydrides at the stressed crack tip by the diffusive ingress of hydrogen into this region. The driving force for the diffusion flux is provided by the local stress gradient which interacts with both hydrogen atoms in solution and hydrogen atoms being dissolved and reprecipitated at the crack tip. The model is developed using concepts of elastoplastic fracture mechanics. Stage I crack growth is controlled by hydrides growing in the elastic stress gradient, while Stage II is controlled by hydride growth in the plastic zone at the crack tip. Recent experimental observations are presented which indicate that the process occurs in an intermittent fashion; hydride clusters accumulate at the crack tip followed by unstable crack advance and subsequent crack arrest in repeated cycles

  10. Mechanisms of hydrogen induced delayed cracking in hydride forming materials

    International Nuclear Information System (INIS)

    Dutton, R.; Nuttall, K.; Puls, M.P.; Simpson, L.A.

    1977-01-01

    Mechanisms which have been formulated to describe delayed hydrogen cracking in hydride-forming metals are reviewed and discussed. Particular emphasis is placed on the commercial alloy Zr-2.5 pct Nb which is extensively used in nuclear reactor core components. A quantitative model for hydrogen cracking in this material is presented and compared with available experimental data. The kinetics of crack propagation are controlled by the growth of hydrides at the stressed crack tip by the diffusive ingress of hydrogen into this region. The driving force for the diffusion flux is provided by the local stress gradient which interacts with both hydrogen atoms in solution and hydrogen atoms being dissolved and reprecipitated at the crack tip. The model is developed using concepts of elastoplastic fracture mechanics. Stage I crack growth is controlled by hydrides growing in the elastic stress gradient, while Stage II is controlled by hydride growth in the plastic zone at the crack tip. Recent experimental observations are presented which indicate that the process occurs in an intermittent fashion; hydride clusters accumulate at the crack tip followed by unstable crack advance and subsequent crack arrest in repeated cycles. 55 refs., 6 figs

  11. U.S. Advanced Materials Development Program for steam generators

    International Nuclear Information System (INIS)

    Patriarca, P.; Harkness, S.D.; Duke, J.M.

    1975-01-01

    The selection of construction materials for LMFBR steam generators is reviewed, presenting the advantages and limitations of 2 1 / 2 Cr-1 Mo steel selected for the Clinch River Breeder Reactor Plant. These limitations indicate that further development of high-strength ferritic steels containing 9 to 12 percent Cr and the high-nickel Alloy 800 could lead to superior materials, and programs to develop these materials have been started. Combustion Engineering has surveyed the experience with the high-strength ferritic steels and prepared ingots of 26 selected compositions. Charpy V-notch tests and metallography have been used to characterize these alloys, and optimum welding rod compositions for these alloys are under development. Westinghouse-Tampa is undertaking a program to gain code acceptance of Alloy 800. A program has been set up to provide the information required for design, justification, and fabrication of reliable components. Progress has been made on characterization, the role of tertiary creep in failure, and the development of welding processes. (U.S.)

  12. Foreign Material Exclusion Program at CNE Cernavoda Nuclear Generating Station

    Energy Technology Data Exchange (ETDEWEB)

    Urjan, Daniel [S.N. ' Nuclearelectrica' SA, CNE Cernavoda Nuclear Power Plant, Medgidiei 2 Street, 905200 Cernavoda, Constanta (Romania)

    2008-07-01

    In the face of a continuing attention to operations and maintenance costs at nuclear power plants, the future of the industry depends largely upon increasing plant availability and improving operating efficiency. The success in achieving these objectives is dependent upon the success of each plant's equipment maintenance program. Preventing the introduction of foreign materials into a nuclear power plant system or component requires a careful, thoughtful, and professional approach by all site personnel. This paper describes a proactive approach to prevent the introduction of foreign material into systems and components, by providing an overview of technical considerations required to develop, implement, and manage a foreign material exclusion program at CNE Cernavoda Unit 1 and 2 Nuclear Power Station. It is also described an example of Foreign Material Intrusion which happened during the 2003 planned maintenance outage at Cernavoda Unit no.1. This paper also defines personnel responsibilities and key nomenclature and a means for evaluating prospective work tasks and activities against standardized criteria, in order to identify the appropriate level of the required FME controls. (author)

  13. Foreign Material Exclusion Program at CNE Cernavoda Nuclear Generating Station

    Energy Technology Data Exchange (ETDEWEB)

    Urjan, Daniel [S.N. ' Nuclearelectrica' SA, CNE Cernavoda Nuclear Power Plant, Medgidiei 2 Street, 905200 Cernavoda, Constanta (Romania)

    2008-07-01

    In the face of a continuing attention to operations and maintenance costs at nuclear power plants, the future of the industry depends largely upon increasing plant availability and improving operating efficiency. The success in achieving these objectives is dependent upon the success of each plant's equipment maintenance program. Preventing the introduction of foreign materials into a nuclear power plant system or component requires a careful, thoughtful, and professional approach by all site personnel. This paper describes a proactive approach to prevent the introduction of foreign material into systems and components, by providing an overview of technical considerations required to develop, implement, and manage a foreign material exclusion program at CNE Cernavoda Unit 1 and 2 Nuclear Power Station. It is also described an example of Foreign Material Intrusion which happened during the 2003 planned maintenance outage at Cernavoda Unit no.1. This paper also defines personnel responsibilities and key nomenclature and a means for evaluating prospective work tasks and activities against standardized criteria, in order to identify the appropriate level of the required FME controls. (author)

  14. Foreign Material Exclusion Program at CNE Cernavoda Nuclear Generating Station

    International Nuclear Information System (INIS)

    Urjan, Daniel

    2008-01-01

    In the face of a continuing attention to operations and maintenance costs at nuclear power plants, the future of the industry depends largely upon increasing plant availability and improving operating efficiency. The success in achieving these objectives is dependent upon the success of each plant's equipment maintenance program. Preventing the introduction of foreign materials into a nuclear power plant system or component requires a careful, thoughtful, and professional approach by all site personnel. This paper describes a proactive approach to prevent the introduction of foreign material into systems and components, by providing an overview of technical considerations required to develop, implement, and manage a foreign material exclusion program at CNE Cernavoda Unit 1 and 2 Nuclear Power Station. It is also described an example of Foreign Material Intrusion which happened during the 2003 planned maintenance outage at Cernavoda Unit no.1. This paper also defines personnel responsibilities and key nomenclature and a means for evaluating prospective work tasks and activities against standardized criteria, in order to identify the appropriate level of the required FME controls. (author)

  15. Employing the Mathcad program within the course of Theoretical Mechanics

    Directory of Open Access Journals (Sweden)

    Kurilin Alexander V.

    2016-01-01

    Full Text Available The author shares his experience in using the «Mathcad» software for conducting classes on «Theoretical Mechanics» in the University course. The program «Mathcad» combines a simple user interface and powerful mathematical tools which can be employed for different mechanical problems. It gives invaluable help in evaluating analytically and numerically many difficult integrals, in solving differential equations, in picturing graphics and can also simulate different mechanical phenomena with the computer. This allows significantly to expand the range of topics that can be considered in the standard University course of «Theoretical Mechanics» and gives students an opportunity to concentrate on practical problems, avoiding unnecessary routine of mathematical calculations. As an example the author considers one famous problem of the Lagrange analytical mechanics associated with the body motion in the field of gravity in the presence of stationary holonomic constraints.

  16. Materials Inventory Database for the Light Water Reactor Sustainability Program

    Energy Technology Data Exchange (ETDEWEB)

    Kazi Ahmed; Shannon M. Bragg-Sitton

    2013-08-01

    Scientific research involves the purchasing, processing, characterization, and fabrication of many sample materials. The history of such materials can become complicated over their lifetime – materials might be cut into pieces or moved to various storage locations, for example. A database with built-in functions to track these kinds of processes facilitates well-organized research. The Material Inventory Database Accounting System (MIDAS) is an easy-to-use tracking and reference system for such items. The Light Water Reactor Sustainability Program (LWRS), which seeks to advance the long-term reliability and productivity of existing nuclear reactors in the United States through multiple research pathways, proposed MIDAS as an efficient way to organize and track all items used in its research. The database software ensures traceability of all items used in research using built-in functions which can emulate actions on tracked items – fabrication, processing, splitting, and more – by performing operations on the data. MIDAS can recover and display the complete history of any item as a simple report. To ensure the database functions suitably for the organization of research, it was developed alongside a specific experiment to test accident tolerant nuclear fuel cladding under the LWRS Advanced Light Water Reactor Nuclear Fuels Pathway. MIDAS kept track of materials used in this experiment from receipt at the laboratory through all processes, test conduct and, ultimately, post-test analysis. By the end of this process, the database proved to be right tool for this program. The database software will help LWRS more efficiently conduct research experiments, from simple characterization tests to in-reactor experiments. Furthermore, MIDAS is a universal tool that any other research team could use to organize their material inventory.

  17. Environmental, economic, and energy impacts of material recovery facilities. A MITE Program evaluation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This report documents an evaluation of the environmental, economic, and energy impacts of material recovery facilities (MRFs) conducted under the Municipal Solid Waste Innovative Technology Evaluation (MITE) Program. The MITE Program is sponsored by the US Environmental Protection Agency to foster the demonstration and development of innovative technologies for the management of municipal solid waste (MSW). This project was also funded by the National Renewable Energy Laboratory (NREL). Material recovery facilities are increasingly being used as one option for managing a significant portion of municipal solid waste (MSW). The owners and operators of these facilities employ a combination of manual and mechanical techniques to separate and sort the recyclable fraction of MSW and to transport the separated materials to recycling facilities.

  18. Breakage mechanics for granular materials in surface-reactive environments

    Science.gov (United States)

    Zhang, Yida; Buscarnera, Giuseppe

    2018-03-01

    It is known that the crushing behaviour of granular materials is sensitive to the state of the fluids occupying the pore space. Here, a thermomechanical theory is developed to link such macroscopic observations with the physico-chemical processes operating at the microcracks of individual grains. The theory relies on the hypothesis that subcritical fracture propagation at intra-particle scale is the controlling mechanism for the rate-dependent, water-sensitive compression of granular specimens. First, the fracture of uniaxially compressed particles in surface-reactive environments is studied in light of irreversible thermodynamics. Such analysis recovers the Gibbs adsorption isotherm as a central component linking the reduction of the fracture toughness of a solid to the increase of vapour concentration. The same methodology is then extended to assemblies immersed in wet air, for which solid-fluid interfaces have been treated as a separate phase. It is shown that this choice brings the solid surface energy into the dissipation equations of the granular matrix, thus providing a pathway to (i) integrate the Gibbs isotherm with the continuum description of particle assemblies and (ii) reproduce the reduction of their yield strength in presence of high relative humidity. The rate-effects involved in the propagation of cracks and the evolution of breakage have been recovered by considering non-homogenous dissipation potentials associated with the creation of surface area at both scales. It is shown that the proposed model captures satisfactorily the compression response of different types of granular materials subjected to varying relative humidity. This result was achieved simply by using parameters based on the actual adsorption characteristics of the constituting minerals. The theory therefore provides a physically sound and thermodynamically consistent framework to study the behaviour of granular solids in surface-reactive environments.

  19. Multimedia Approach to Self-Paced Individualized Instruction in Automotive Mechanics and Other Vocational Programs. Final Report.

    Science.gov (United States)

    Ozarka Vocational Technical School, Melbourne, AR.

    A project developed, field tested, implemented, and disseminated a management system, support materials, and references for a self-paced individualized instructional program in automotive mechanics and food services. During the program, the Planwriter component of the SAGE/Compute-a-Match Assessment System was used to develop a management system…

  20. Mechanical and thermophysical properties of graphite/polyimide composite materials

    Science.gov (United States)

    Rummler, D. R.; Clark, R. K.

    1979-01-01

    An on-going program to characterize advanced composites for up to 50,000 hours of exposure to simulated supersonic cruise environments is summarized. Results are presented for up to 25,000 hours of thermal exposure and 10,000 hours of flight simulation at temperatures up to 560K (550 F) with emphasis on HTS/710 graphite/polyimide composite material. Results to date indicate that the maximum use temperature for HTS/710 may be reduced to 505K (450 F) for long-time (1000 hours) application such as the supersonic transport. Preliminary thermophysical properties data for HTS/PMR15 graphite/polyimide were generated. These data include thermal conductivity, thermal expansion, and specific heat from 115K (-252 F) to 590K (600 F) and emittance at room temperature and 590K (600 F). The purpose in generating these data was to validate use of state-of-the-art property measurement methods for advanced graphite fiber reinforced resin matrix composites. Based on results to this point, thermal expansion measurements for composites are most difficult to perform. A high degree of caution in conducting thermal expansion tests and analyzing results is required to produce reliable data.

  1. THE NUCLEAR MATERIAL MEASUREMENT PROGRAM PLAN FOR GOSATOMNADZOR OF RUSSIA

    International Nuclear Information System (INIS)

    Bokov, Dmitry; Byers, Kenneth R.

    2003-01-01

    As the Russian State regulatory agency responsible for oversight of nuclear material control and accounting (MC and A), Gosatomnadzor of Russia determines the status of the MC and A programs at Russian facilites by testing the nuclear material inventory for accounting record accuracy. Currently, Gosatomnadzor is developing and implementing an approach to planning and conducting MC and A inspections using non-destructive assay (NDA) instruments that will provide for consistent application of MC and A measurement inspection objectives throughtout Russia. This Gosatomnadzor NDA Program Plan documents current NDA measurement capability in all regions of Gosatomnadzor; provides justification for upgrades to equipment, procedures and training; and defines the inspector-facility operator interface as it relates to NDA measurement equipment use. This plan covers a three-year measurement program cycle, but will be reviewed and updated annually to ensure that adequate inspection resources are available to meet the demands of the inspection schedule. This paper presents the elements of this plan and describes the process by which Gosatomnadzor ensures that its NDA instruments are effectively utilized, procedures are developed and certified, and inspection personnel are properly trained to provide assurance that Russian nuclear facilities are in compliance with Russian MC and A regulations.

  2. Contact mechanics and friction for transversely isotropic viscoelastic materials

    NARCIS (Netherlands)

    Mokhtari, Milad; Schipper, Dirk J.; Vleugels, N.; Noordermeer, Jacobus W.M.; Yoshimoto, S.; Hashimoto, H.

    2015-01-01

    Transversely isotropic materials are an unique group of materials whose properties are the same along two of the principal axes of a Cartesian coordinate system. Various natural and artificial materials behave effectively as transversely isotropic elastic solids. Several materials can be classified

  3. Material balance area custodian performance evaluation program at PNL

    International Nuclear Information System (INIS)

    Dickman, D.A.

    1991-01-01

    This paper reports that the material balance area (MBA) custodian has primary responsibility for control and accountability of nuclear material within an MBA. In this role, the custodian operates as an extension of the facility material control and accountability (MC and A) organization. To effectively meet administrative requirements and protection needs, the custodian must be fully trained in all aspects of MC and A related to the MBA, and custodian performance must be periodically evaluated. U.S. Department of Energy (DOE) Policy requires that each facility provide for a program which ensures that personnel performing MC and A functions are trained and/or qualified to perform their duties and responsibilities and knowledgeable of requirements and procedures related to their functions. the MBA Custodian Performance Evaluation Program at Pacific Northwest Laboratory (PNL) uses a variety of assessment techniques to meet this goal, including internal and independent MBA audits, periodic custodian testing, limited scope performance tests, daily monitoring of MC and A documentation, and reviewing custodian performance during physical inventories

  4. Fundamental Electronic Structure Characteristics and Mechanical Behavior of Aerospace Materials

    National Research Council Canada - National Science Library

    Freeman, Arthur J; Kontsevoi, Oleg Y; Gornostyrev, Yuri N; Medvedeva, Nadezhda I

    2008-01-01

    To fulfill the great potential of intermetallic alloys for high temperature structural applications, it is essential to understand the mechanisms controlling their mechanical behavior on the microscopic level...

  5. Material transfer mechanisms between aluminum and fluorinated carbon interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Sen, F.G. [NSERC/General Motors of Canada Industrial Research Chair, Department of Mechanical, Automotive and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, N9B 3P4 (Canada); Qi, Y. [Chemical Sciences and Materials Systems Laboratory, General Motors R and D Center, 30500 Mound Road, Warren, MI 48090-9055 (United States); Alpas, A.T., E-mail: aalpas@uwindsor.ca [NSERC/General Motors of Canada Industrial Research Chair, Department of Mechanical, Automotive and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, N9B 3P4 (Canada)

    2011-04-15

    First-principles calculations and sliding contact experiments were conducted to elucidate material transfer mechanisms between aluminum and fluorinated carbon (diamond, diamond-like carbon (DLC)) surfaces. An interface model that examined interactions between Al (1 1 1) and F-terminated diamond (1 1 1) surfaces revealed that F atoms would transfer to the Al surface in increasing quantities with an increase in the contact pressure, and this F transfer would lead to the formation of a stable AlF{sub 3} compound at the Al surface. The presence of AlF{sub 3} on the transfer layers formed at the Al counterface placed in sliding contact against DLC containing 3 at.% F was confirmed by both X-ray photoelectron spectroscopy and cross-sectional focussed-ion beam transmission electron microscopy analyses. The coefficient of friction (COF) of the DLC coating was high initially due to deformation and wear of Al counterface, but formation of -OH and -H passivated C-rich transfer layers on Al reduced the COF to a low steady-state value of 0.20. The repulsive forces generated between the two F-passivated surfaces further decreased the COF to 0.14.

  6. Material transfer mechanisms between aluminum and fluorinated carbon interfaces

    International Nuclear Information System (INIS)

    Sen, F.G.; Qi, Y.; Alpas, A.T.

    2011-01-01

    First-principles calculations and sliding contact experiments were conducted to elucidate material transfer mechanisms between aluminum and fluorinated carbon (diamond, diamond-like carbon (DLC)) surfaces. An interface model that examined interactions between Al (1 1 1) and F-terminated diamond (1 1 1) surfaces revealed that F atoms would transfer to the Al surface in increasing quantities with an increase in the contact pressure, and this F transfer would lead to the formation of a stable AlF 3 compound at the Al surface. The presence of AlF 3 on the transfer layers formed at the Al counterface placed in sliding contact against DLC containing 3 at.% F was confirmed by both X-ray photoelectron spectroscopy and cross-sectional focussed-ion beam transmission electron microscopy analyses. The coefficient of friction (COF) of the DLC coating was high initially due to deformation and wear of Al counterface, but formation of -OH and -H passivated C-rich transfer layers on Al reduced the COF to a low steady-state value of 0.20. The repulsive forces generated between the two F-passivated surfaces further decreased the COF to 0.14.

  7. The mass transfer mechanism of fissile material due to fission

    International Nuclear Information System (INIS)

    Shafrir, N.H.

    1975-01-01

    A thin 252 Cf source of a mean thickness of an approXimately mono-atomic layer was used as an experimental model for the study of the basic mechanism of the knock-on process taking place in fissile material. Because of the thinness of the source it can be assumed that mainly primary knock-ons are formed. The ejection rate of knock-ons created by direct collisions between fission fragments and source atoms was measured as follows: the ejected atoms were collected in high vacuum on a catcher foil and 252 Cf determined by alpha spectroscopy using a silicon surface barrier detector. The number of 252 Cf ejected from the source in unit time could thus be determined while considering the anisotropy of ejection, geometry and counting efficiency. Taking into account the chemical composition of the source, eta(theor.) = 252 Cf atoms/fission was obtained. This result can be considered in reasonable agreement with experiment confirming that under the experimental conditions described, practically no knock-on cascade is formed. (B.G.)

  8. Material control and accounting self-test program design

    International Nuclear Information System (INIS)

    Eggers, R.F.; Wilson, R.L.; Byers, K.R.

    1981-01-01

    This paper describes a controversial but potentially beneficial MCandA strategy that has not been widely attempted in the past, called Self-Test. In this strategy a processor of Strategic Special Nuclear Material (SSNM) devises a program of internally administered tests to determine if the MCandA system performs in a reliable, expedient manner in the face of a simulated loss or compromise. Self-Test procedures would include, for example, the actual removal of SSNM from process equipment in order to determine whether the MCandA system will detect the simulated theft. Self-Test programs have several potential problems. However, an approach with the potential for solving many of these problems has been devised and is discussed

  9. Bibliography of published material related to the Soviet PNE Program

    International Nuclear Information System (INIS)

    Ledbetter, G.P.; Nordyke, M.D.

    1977-01-01

    Scientists in the Soviet Union have published many papers that provide details about the Soviet program for the peaceful use of nuclear explosions. Over the years much of this material has been gathered at the Lawrence Livermore Laboratory into what has become a sizeable collection. The bibliography of 334 references provides a useful record of the material available in that collection. The bibliography is divided into three main parts. Part I lists articles alphabetically. In Part II, the same articles are arranged by subject; many of them are included under more than one subject category. Part III is a list of important collections of papers. These collections provide many of the articles listed in Parts I and II

  10. The role of programmed and emergent mechanisms of coordination

    DEFF Research Database (Denmark)

    Prætorius, Thim

    Hospitals face substantial coordination challenges. To meet this hospitals more and more use standardized work processes such as care pathways. By drawing on recent coordination theory that increasingly emphasizes the role of lateral and emergent interactions alongside traditional, programmed...... mechanisms of coordination, this paper finds that standardized work processes such as care pathways should be considered as a bundle of coordination mechanisms—plans and rules, objects, routines, roles and proximity—rather than a mechanism of its own. The bundle builds the accountability, predictability...... and common understanding needed to coordinate standardized care tasks. The analysis lends theoretical insights to the traditional view that see standardized work processes as programmed processes. For health care workers who design, implement and use care pathways to solve care tasks, the analysis calls...

  11. Propulsion system materials program. Semiannual progress report, October 1995--March 1996

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1996-07-01

    This portion of the program is identified as program element 1.0 within the work breakdown structure (WBS). It contains five subelements: (1) Monolithics, (2) Ceramic Composites, (3) Thermal and Wear Coatings, (4) Joining, and (5) Ceramic Machining. Ceramic research conducted within the Monolithics subelement currently includes work activities on low Cost Si{sub 3}N{sub 4} powder, green state ceramic fabrication, characterization, and densification, and on structural, mechanical, and physical properties of these ceramics. Research conducted within the Ceramic Composites subelement currently includes silicon nitride and oxide-based composites, and low expansion materials. Research conducted in the Thermal and Wear Coatings subelement is currently limited to oxide-based coatings and involves coating synthesis, characterization, and determination of the mechanical and physical properties of the coatings. Research conducted in the Joining subelement currently includes studies of processes to produce strong, stable joints between zirconia ceramics and iron-base alloys. As part of an expanded effort to reduce the cost of ceramic components, a new initiative in cost effective machining has been started. A major objective of the research in the Materials and Processing program element is to systematically advance the understanding of the relationships between ceramic raw materials such as powders and reactant gases, the processing variables involved in producing the ceramic materials, and the resultant microstructures and physical and mechanical properties of the ceramic materials. Success in meeting this objective will provide U.S. companies with new or improved ways for producing economical, highly reliable ceramic components for advanced heat engines.

  12. Mechanical behaviour of dental composite filling materials using digital holography

    OpenAIRE

    Monteiro, J.M.; Lopes, H.; Vaz, M.A.P.; Campos, J.C. Reis

    2010-01-01

    One of the most common clinical problems in dentistry is tooth decay. Among the dental filling materials used to repair tooth structure that has been destroyed by decay are dental amalgam and composite materials based on acrylics. Dental amalgam has been used by dentists for the past 150 years as a dental restorative material due to its low cost, ease of application, strength, durability, and bacteriostatic effects. However its safety as a filling material has been questioned due to th...

  13. Thermo-hydro-mechanical tests of buffer material

    Energy Technology Data Exchange (ETDEWEB)

    Pintado, X.; Hassan, Md. M.; Martikainen, J. [B and Tech Oy, Helsinki (Finland)

    2013-10-15

    MX-80 bentonite is the reference clay material for the buffer component planned to be used in the deep geological repository for the disposal of spent nuclear fuel in Finland. The buffer presents complex thermo-hydro-mechanical behavior which is modeled with different constitutive models for heat flow, water flow and stress-strain evolution in the buffer. Thermo, hydro and mechanical models need parameters to evaluate the THM-behavior. These modeling parameters were determined by performing series of laboratory experiments as follows: Water retention curve tests were performed on compacted bentonite samples, encompassing a range of initial dry density values from 1397 to 1718 kg/m{sup 3} as the initial water content was around of 5-8 %. The water retention curve was determined by imposing different suctions to the samples and the suctions were then checked using capacitive hygrometer and chilled mirror psychrometer. Oedometer tests were performed on compacted bentonite samples, encompassing a range of initial dry density values from 1590 to 1750 kg/m{sup 3} as the initial water content was around of 6 %. Samples were saturated with tap water, 35 or 70 g/L salt solutions. Infiltration tests were performed on compacted unsaturated bentonite samples, encompassing a range of initial dry density values from 1400 to 1720 kg/m{sup 3} as the initial water content was approximately between 4-7 %. Samples were saturated with tap water, 0.87, 35 or 70 g/L salt solutions. Tortuosity tests were performed on bentonite samples, encompassing a range of dry density values from 1460 to 1750 kg/m{sup 3} and the degree of saturation varied between 33-93 %. Thermal conductivity tests were performed on compacted bentonite samples, encompassing a range of dry density values from 1545 to 1715 kg/m{sup 3} and the degree of saturation varied between 31-88 %. The measurement was performed using a thermal needle probe. The general trend of all analyzed parameters was as expected when dry

  14. Thermo-hydro-mechanical tests of buffer material

    International Nuclear Information System (INIS)

    Pintado, X.; Hassan, Md. M.; Martikainen, J.

    2013-10-01

    MX-80 bentonite is the reference clay material for the buffer component planned to be used in the deep geological repository for the disposal of spent nuclear fuel in Finland. The buffer presents complex thermo-hydro-mechanical behavior which is modeled with different constitutive models for heat flow, water flow and stress-strain evolution in the buffer. Thermo, hydro and mechanical models need parameters to evaluate the THM-behavior. These modeling parameters were determined by performing series of laboratory experiments as follows: Water retention curve tests were performed on compacted bentonite samples, encompassing a range of initial dry density values from 1397 to 1718 kg/m 3 as the initial water content was around of 5-8 %. The water retention curve was determined by imposing different suctions to the samples and the suctions were then checked using capacitive hygrometer and chilled mirror psychrometer. Oedometer tests were performed on compacted bentonite samples, encompassing a range of initial dry density values from 1590 to 1750 kg/m 3 as the initial water content was around of 6 %. Samples were saturated with tap water, 35 or 70 g/L salt solutions. Infiltration tests were performed on compacted unsaturated bentonite samples, encompassing a range of initial dry density values from 1400 to 1720 kg/m 3 as the initial water content was approximately between 4-7 %. Samples were saturated with tap water, 0.87, 35 or 70 g/L salt solutions. Tortuosity tests were performed on bentonite samples, encompassing a range of dry density values from 1460 to 1750 kg/m 3 and the degree of saturation varied between 33-93 %. Thermal conductivity tests were performed on compacted bentonite samples, encompassing a range of dry density values from 1545 to 1715 kg/m 3 and the degree of saturation varied between 31-88 %. The measurement was performed using a thermal needle probe. The general trend of all analyzed parameters was as expected when dry density, water content, and

  15. Rock mechanics in the National Waste Terminal Storage Program

    International Nuclear Information System (INIS)

    Monsees, J.E.; Wigley, M.R.

    1982-01-01

    The overall objective of the rock mechanics program of the Office of Nuclear Waste Isolation is to predict the response of a rock mass hosting a waste repository during its construction, operation, and postoperational phases. The operational phase is expected to be 50 to 100 yr; the postoperational phase will last until the repository no longer poses any potential hazard to the biosphere, a period that may last several thousand years. The rock mechanics program is concerned with near-field effects on mine stability, as well as far-field effects relative to the overall integrity of the geologic waste isolation system. To accomplish these objectives, the rock mechanics program has established interactive studies in numerical simulation, laboratory testing, and field testing. The laboratory and field investigations provide input to the numerical simulations and give an opportunity for verification and validation of the predictive capabilities of the computer codes. Ultimately the computer codes will be used to predict the response of the geologic system to the development of a repository. 3 references, 5 figures

  16. Mechanical characterization of selected adhesives and bulk materials at liquid nitrogen and room temperatures

    International Nuclear Information System (INIS)

    Fitzpatrick, C.M.; Stoddart, W.C.T.

    1977-01-01

    This paper presents the results of a series of mechanical tests on selected adhesives and bulk materials. The materials tested are of general interest to designers of magnets for cryogenic service and include several epoxies, a varnish, a B-stage glass cloth, insulation papers, and commercially available fiber-reinforced composites. These tests were performed at room temperature (293 K) and at liquid nitrogen temperature (77 K). The tests include both simple tension tests and lap shear tests with various adherends. The parameters critical to tensile or bond strength were varied as part of the test program. The procedures used to manufacture and test these specimens and the results of the tests are reported in this paper

  17. Reactor materials program process water component failure probability

    International Nuclear Information System (INIS)

    Daugherty, W. L.

    1988-01-01

    The maximum rate loss of coolant accident for the Savannah River Production Reactors is presently specified as the abrupt double-ended guillotine break (DEGB) of a large process water pipe. This accident is not considered credible in light of the low applied stresses and the inherent ductility of the piping materials. The Reactor Materials Program was initiated to provide the technical basis for an alternate, credible maximum rate LOCA. The major thrust of this program is to develop an alternate worst case accident scenario by deterministic means. In addition, the probability of a DEGB is also being determined; to show that in addition to being mechanistically incredible, it is also highly improbable. The probability of a DEGB of the process water piping is evaluated in two parts: failure by direct means, and indirectly-induced failure. These two areas have been discussed in other reports. In addition, the frequency of a large bread (equivalent to a DEGB) in other process water system components is assessed. This report reviews the large break frequency for each component as well as the overall large break frequency for the reactor system

  18. Mechanical properties of the beetle elytron, a biological composite material

    Science.gov (United States)

    We determined the relationship between composition and mechanical properties of elytral (modified forewing) cuticle of the beetles Tribolium castaneum and Tenebrio molitor. Elytra of both species have similar mechanical properties at comparable stages of maturation (tanning). Shortly after adult ecl...

  19. LAMI - a planned Brazilian facility to investigate the mechanical and physical properties of structural materials under irradiation

    International Nuclear Information System (INIS)

    Andrade, Arnaldo H.P.; Lobo, Raquel M.

    2011-01-01

    The LAMI (Laboratorio de Materiais Irradiados) is a hot laboratory designed to the characterization of irradiated structural material and will constitute one of the main installations of the Brazilian Multipurpose Reactor (RMB). The strong points of LAMI are: to contribute, through theoretical and experimental investigations, to the development of knowledge in materials science in order to be able to predict the evolution of the physical and mechanical material properties under service conditions (irradiation, thermomechanical solicitation, influence of the environment, etc); to characterize the properties of the materials used in the nuclear industry in order to determine their performance and to be able to predict their life expectancy; to establish, maintain and make use of the database generated by these data and to provide expertise on industrial components, in particular to investigate strain or rupture mechanisms. The test materials can be irradiated or not, and originate from surveillance programs, experimental neutron irradiations or simulated irradiation with charged particles. The main line of LAMI will have 10 shielded hot cells. The building also will have an area dedicated to micro and nano structural materials analysis. The mechanical characterization to be carried out within LAMI includes mechanical tests on irradiated materials, comprehension of behavior and damage processes and the incorporation of the test data results in a data bank for capitalization of test results. Planned materials to be tested are going to be metallic alloys used in industrial and experimental reactor: pressure vessel steels, internal stainless steels, austeno-ferritic steels, zirconium alloys and aluminum alloys. (author)

  20. Composite materials research and education program: The NASA-Virginia Tech composites program

    Science.gov (United States)

    Herakovich, C. T.

    1980-01-01

    Major areas of study include: (1) edge effects in finite width laminated composites subjected to mechanical, thermal and hygroscopic loading with temperature dependent material properties and the influence of edge effects on the initiation of failure; (2) shear and compression testing of composite materials at room and elevated temperatures; (3) optical techniques for precise measurement of coefficients of thermal expansion of composites; (4) models for the nonlinear behavior of composites including material nonlinearity and damage accumulation and verification of the models under biaxial loading; (5) compressive failure of graphite/epoxy plates with circular holes and the buckling of composite cylinders under combined compression and torsion; (6) nonlinear mechanical properties of borsic/aluminum, graphite/polyimide and boron/aluminum; (7) the strength characteristics of spliced sandwich panels; and (8) curved graphite/epoxy panels subjected to internal pressure.

  1. Validation of a fracture mechanics approach to nuclear transportation cask design through a drop test program

    International Nuclear Information System (INIS)

    Sorenson, K.B.

    1986-01-01

    Sandia National Laboratories (SNL), under contract to the Department of Energy, is conducting a research program to develop and validate a fracture mechanics approach to cask design. A series of drop tests of a transportation cask is planned for the summer of 1986 as the method for benchmarking and, thereby, validating the fracture mechanics approach. This paper presents the drop test plan and background leading to the development of the test plan including structural analyses, material characterization, and non-destructive evaluation (NDE) techniques necessary for defining the test plan properly

  2. Mechanical alloying nanotechnology, materials science and powder metallurgy

    CERN Document Server

    El-Eskandarany, M Sherif

    2015-01-01

    This book is a detailed introduction to mechanical alloying, offering guidelines on the necessary equipment and facilities needed to carry out the process and giving a fundamental background to the reactions taking place. El-Eskandarany, a leading authority on mechanical alloying, discusses the mechanism of powder consolidations using different powder compaction processes. A new chapter will also be included on thermal, mechanically-induced and electrical discharge-assisted mechanical milling. Fully updated to cover recent developments in the field, this second edition also introduces new a

  3. LASL analytical chemistry program for fissionable materials safeguards

    International Nuclear Information System (INIS)

    Jackson, D.D.; Marsh, S.F.

    1979-01-01

    Gas-solid reactions at elevated temperature, used previously to convert uranium in refractory forms to species readily soluble in acid, are being applied to thorium materials. A microgram-sensitive spectrophotometric method was developed for determining uranium and the LASL Automated Spectrophotometer has been modified to use it. The instrument now is functional for determining milligram amounts of plutonium, and milligram and microgram amounts of uranium. Construction of an automated controlled-potential-coulometric analyzer has been completed. It is giving design performance of 0.1% relative standard deviation for the determination of plutonium using a method developed especially for the instrument. A method has been developed for the microcomplexometric titration of uranium in its stable (VI) oxidation state. A color probe analyzer assembled for this titration also has been used for microcomplexometric titration of thorium. The present status of reference materials prepared for NBS and for the SALE program, as well as examples of working reference materials prepared for use with nondestructive analyzers, is given. The interlaboratory measured value of the 239 Pu half-life is 24,119 y. Just completed measurement of the half life of 241 Pu is 14.38 y. Measurement of the 240 Pu half life is in progress

  4. Report of the Material Control and Material Accounting Task Force: the role of material control and material accounting in the safeguards program

    International Nuclear Information System (INIS)

    1978-03-01

    Results are presented of NRC Task Force investigations to identify the functions of a safeguards program in relation to the NRC safeguards objective, define the role and objectives of material control and material accounting systems within that program, develop goals for material control and material accounting based on those roles and objectives, assess current material control and material accounting requirements and performance levels in the light of the goals, and recommend future actions needed to attain the proposed goals. It was found that the major contribution of material accounting to the safeguards program is in support of the assurance function. It also can make secondary contributions to the prevention and response functions. In the important area of loss detection, a response measure, it is felt that limitations inherent in material accounting for some fuel cycle operations limit its ability to operate as a primary detection system to detect a five formula kilogram loss with high assurance (defined by the Task Force as a probability of detection of 90 percent or more) and that, in those cases, material accounting can act only in a backup role. Physical security and material control must make the primary contributions to the prevention and detection of theft, so that safeguards do not rely primarily for detection capabilities on material accounting. There are several areas of accounting that require more emphasis than is offered by the current regulatory base. These areas include: timely shipper-receiver difference analysis and reconciliation; a demand physical inventory capability; improved loss localization;discard measurement verification; timely recovery of scrap; improved measurement and record systems; and limits on cumulative inventory differences and shipper-receiver differences. An increased NRC capability for monitoring and analyzing licensee accounting data and more timely and detailed submittals of data to NRC by licensees are recommended

  5. Nanomechanical strength mechanisms of hierarchical biological materials and tissues.

    Science.gov (United States)

    Buehler, Markus J; Ackbarow, Theodor

    2008-12-01

    Biological protein materials (BPMs), intriguing hierarchical structures formed by assembly of chemical building blocks, are crucial for critical functions of life. The structural details of BPMs are fascinating: They represent a combination of universally found motifs such as alpha-helices or beta-sheets with highly adapted protein structures such as cytoskeletal networks or spider silk nanocomposites. BPMs combine properties like strength and robustness, self-healing ability, adaptability, changeability, evolvability and others into multi-functional materials at a level unmatched in synthetic materials. The ability to achieve these properties depends critically on the particular traits of these materials, first and foremost their hierarchical architecture and seamless integration of material and structure, from nano to macro. Here, we provide a brief review of this field and outline new research directions, along with a review of recent research results in the development of structure-property relationships of biological protein materials exemplified in a study of vimentin intermediate filaments.

  6. Animal Hairs as Water-stimulated Shape Memory Materials: Mechanism and Structural Networks in Molecular Assemblies

    Science.gov (United States)

    Xiao, Xueliang; Hu, Jinlian

    2016-05-01

    Animal hairs consisting of α-keratin biopolymers existing broadly in nature may be responsive to water for recovery to the innate shape from their fixed deformation, thus possess smart behavior, namely shape memory effect (SME). In this article, three typical animal hair fibers were first time investigated for their water-stimulated SME, and therefrom to identify the corresponding net-points and switches in their molecular and morphological structures. Experimentally, the SME manifested a good stability of high shape fixation ratio and reasonable recovery rate after many cycles of deformation programming under water stimulation. The effects of hydration on hair lateral size, recovery kinetics, dynamic mechanical behaviors and structural components (crystal, disulfide and hydrogen bonds) were then systematically studied. SME mechanisms were explored based on the variations of structural components in molecular assemblies of such smart fibers. A hybrid structural network model with single-switch and twin-net-points was thereafter proposed to interpret the water-stimulated shape memory mechanism of animal hairs. This original work is expected to provide inspiration for exploring other natural materials to reveal their smart functions and natural laws in animals including human as well as making more remarkable synthetic smart materials.

  7. Teaching and Evaluation Materials Utilizing Multiple Representations in Mechanics

    Science.gov (United States)

    Savinainen, A.; Nieminen, P.; Makynen, A.; Viiri, J.

    2013-01-01

    In this paper, we present materials and teaching ideas utilizing multiple representations in the contexts of kinematics and the force concept. These ideas and materials are substantiated by evidence and can be readily used in teaching with no special training. In addition, we briefly discuss two multiple-choice tests based on physics education…

  8. Investigations of construction materials by means of cracking mechanics

    International Nuclear Information System (INIS)

    Bilous, W.; Wasiak, J.

    1995-01-01

    The diagnostic procedure for typical construction materials based on cracking tests has been presented. Results of investigations for aluminium base alloys and tungsten sintered materials have been shown and discussed. Application of the method for pipelines testing has been also performed. 6 figs, 2 tabs

  9. Mechanical properties of wood-based composite materials

    Science.gov (United States)

    Zhiyong Cai; Robert J. Ross

    2010-01-01

    The term composite is used to describe any wood material bonded together with adhesives. The current product mix ranges from fiberboard to laminated beams and components. In this chapter, wood-based composite materials are classified into the following categories: panel products (plywood, oriented strandboard (OSB), particleboard, fiberboard, medium-density fiberboard...

  10. Summary of NRC LWR safety research programs on fuel behavior, metallurgy/materials and operational safety

    International Nuclear Information System (INIS)

    Bennett, G.L.

    1979-09-01

    The NRC light-water reactor safety-research program is part of the NRC regulatory program for ensuring the safety of nuclear power plants. This paper summarizes the results of NRC-sponsored research into fuel behavior, metallurgy and materials, and operational safety. The fuel behavior research program provides a detailed understanding of the response of nuclear fuel assemblies to postulated off-normal or accident conditions. Fuel behavior research includes studies of basic fuel rod properties, in-reactor tests, computer code development, fission product release and fuel meltdown. The metallurgy and materials research program provides independent confirmation of the safe design of reactor vessels and piping. This program includes studies on fracture mechanics, irradiation embrittlement, stress corrosion, crack growth, and nondestructive examination. The operational safety research provides direct assistance to NRC officials concerned with the operational and operational-safety aspects of nuclear power plants. The topics currently being addressed include qualification testing evaluation, fire protection, human factors, and noise diagnostics

  11. Heavy Vehicle Propulsion System Materials Program semiannual progress report for October 1996 through March 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The design of advanced components for high-efficiency diesel engines has, in some cases, pushed the performance envelope for materials of construction past the point of reliable operation. Higher mechanical and tribological stresses and higher temperatures of advanced designs limit the engine designers; advanced materials allow the design of components that may operate reliably at higher stresses and temperatures, thus enabling more efficient engine designs. Advanced materials also offer the opportunity to improve the emissions, NVH, and performance of diesel engines for pickup trucks, vans, and sport utility vehicles. The principal areas of research are: (1) cost effective high performance materials and processing; (2) advanced manufacturing technology; (3) testing and characterization; and (4) materials and testing standards.

  12. Sandia National Laboratories, California Hazardous Materials Management Program annual report : February 2009.

    Energy Technology Data Exchange (ETDEWEB)

    Brynildson, Mark E.

    2009-02-01

    The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Hazardous Materials Management Program. It functions as supporting documentation to the SNL/CA Environmental anagement ystem Program Manual. This program annual report describes the activities undertaken during the past year, and activities planned in future years to implement the Hazardous Materials Management Program, one of six programs that supports environmental management at SNL/CA.

  13. Materials Development Program: Ceramic Technology Project bibliography, 1984--1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    The Ceramic Technology [for Advanced Heat Engines] Project was begun in 1983 to meet the ceramic materials needs of the companion DOE automotive engine program, the Advanced Gas Turbine (AGT) project, and the Heavy Duty Transport (low-heat-rejection, heavy-duty diesel) project. Goal is to develop an industry technology base for reliable and cost effective ceramics for applications in advanced automotive gas turbine and diesel engines. Research areas were identified following extensive input from industry and academia. Majority of research is done by industry (60%); work is also done at colleges and universities, in-house, and at other national laboratories and government agencies. In the beginning, reliability of ceramic components was the key issue. The reliability issues have largely been met and, at the present time, cost is the driving issue, especially in light of the highly cost-sensitive automotive market. Emphasis of the program has now been shifted toward developing cost-effective ceramic components for high-performance engines in the near-term. This bibliography is a compilation of publications done in conjunction with the Ceramic Technology Project since its beginning. Citations were obtained from reports done by participants in the project. We have tried to limit citations to those published and easily located. The end date of 1992 was selected.

  14. Mechanical alignment of particles for use in fabricating superconducting and permanent magnetic materials

    Science.gov (United States)

    Nellis, William J.; Maple, M. Brian

    1992-01-01

    A method for mechanically aligning oriented superconducting or permanently magnetic materials for further processing into constructs. This pretreatment optimizes the final crystallographic orientation and, thus, properties in these constructs. Such materials as superconducting fibers, needles and platelets are utilized.

  15. Materials evaluation programs at the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    Gee, J.T.; Iverson, D.C.; Bickford, D.F.

    1992-01-01

    The Savannah River Site (SRS) has been operating a nuclear fuel cycle since the 1950s to produce nuclear materials in support of the national defense effort. About 83 million gallons of high-level waste produced since operations began has been consolidated by evaporation into 33 million gallons at the waste tank farm. The Department of Energy authorized the construction of the Defense Waste Processing Facility (DWPF), the function of which is to immobilize the waste as a durable borosilicate glass contained in stainless steel canisters prior to the placement of the canisters in a federal repository. The DWPF is now mechanically complete and is undergoing commissioning and run-in activities. A brief description of the DWPF process is provided

  16. Production and Mechanical Characterization of Ballistic Thermoplastic Composite Materials

    OpenAIRE

    D. Korsacilar; C. Atas

    2014-01-01

    In this study, first thermoplastic composite materials /plates that have high ballistic impact resistance were produced. For this purpose, the thermoplastic prepreg and the vacuum bagging technique were used to produce a composite material. Thermoplastic prepregs (resin-impregnated fiber) that are supplied ready to be used, namely high-density polyethylene (HDPE) was chosen as matrix and unidirectional glass fiber was used as reinforcement. In order to compare the fiber c...

  17. Fracture mechanics of polymer mortar made with recycled raw materials

    OpenAIRE

    Jurumenha,Marco Antonio Godoy; Reis,João Marciano Laredo dos

    2010-01-01

    The aim of this work is to show that industrial residues could be used in construction applications so that production costs as well as environmental protection can be improved. The fracture properties of polymer mortar manufactured with recycled materials are investigated to evaluate the materials behaviour to crack propagation. The residues used in this work were spent sand from foundry industry as aggregate, unsaturated polyester resin from polyethylene terephthalate (PET) as matrix and po...

  18. Mechanical properties of polymer-infiltrated-ceramic-network materials.

    Science.gov (United States)

    Coldea, Andrea; Swain, Michael V; Thiel, Norbert

    2013-04-01

    To determine and identify correlations between flexural strength, strain at failure, elastic modulus and hardness versus ceramic network densities of a range of novel polymer-infiltrated-ceramic-network (PICN) materials. Four ceramic network densities ranging from 59% to 72% of theoretical density, resin infiltrated PICN as well as pure polymer and dense ceramic cross-sections were subjected to Vickers Indentations (HV 5) for hardness evaluation. The flexural strength and elastic modulus were measured using three-point-bending. The fracture response of PICNs was determined for cracks induced by Vickers-indentation. Optical and scanning electron microscopy (SEM) was employed to observe the indented areas. Depending on the density of the porous ceramic the flexural strength of PICNs ranged from 131 to 160MPa, the hardness values ranged between 1.05 and 2.10GPa and the elastic modulus between 16.4 and 28.1GPa. SEM observations of the indentation induced cracks indicate that the polymer network causes greater crack deflection than the dense ceramic material. The results were compared with simple analytical expressions for property variation of two phase composite materials. This study points out the correlation between ceramic network density, elastic modulus and hardness of PICNs. These materials are considered to more closely imitate natural tooth properties compared with existing dental restorative materials. Copyright © 2013 Academy of Dental Materials. All rights reserved.

  19. Combining adhesive contact mechanics with a viscoelastic material model to probe local material properties by AFM.

    Science.gov (United States)

    Ganser, Christian; Czibula, Caterina; Tscharnuter, Daniel; Schöberl, Thomas; Teichert, Christian; Hirn, Ulrich

    2017-12-20

    Viscoelastic properties are often measured using probe based techniques such as nanoindentation (NI) and atomic force microscopy (AFM). Rarely, however, are these methods verified. In this article, we present a method that combines contact mechanics with a viscoelastic model (VEM) composed of springs and dashpots. We further show how to use this model to determine viscoelastic properties from creep curves recorded by a probe based technique. We focus on using the standard linear solid model and the generalized Maxwell model of order 2. The method operates in the range of 0.01 Hz to 1 Hz. Our approach is suitable for rough surfaces by providing a defined contact area using plastic pre-deformation of the material. The very same procedure is used to evaluate AFM based measurements as well as NI measurements performed on polymer samples made from poly(methyl methacrylate) and polycarbonate. The results of these measurements are then compared to those obtained by tensile creep tests also performed on the same samples. It is found that the tensile test results differ considerably from the results obtained by AFM and NI methods. The similarity between the AFM results and NI results suggests that the proposed method is capable of yielding results comparable to NI but with the advantage of the imaging possibilities of AFM. Furthermore, all three methods allowed a clear distinction between PC and PMMA by means of their respective viscoelastic properties.

  20. Theoretical model for the hydrogen-material interaction as a basis for prediction of the material mechanical properties

    International Nuclear Information System (INIS)

    Indeitsev, D.A.; Polyanskiy, V.A.; Sukhanov, A.A.; Belyaev, A.A.

    2009-01-01

    The natural law concentration of hydrogen inside the materials has a distribution over the different binding energies. This distribution is changing under the mechanical tension. The model of interaction of the small hydrogen concentration with materials provides one with an instrument for modeling the materials fatigue and destruction, as well as the prediction of material properties during exploitation. The well-known models are of the phenomenological nature. However if one takes into account the physical mechanism then one obtains an accurate model and the instrument for the reliable prediction. The two-continuum model of the solid material is a substantiation for the present study. This model describes the interaction between the low concentration of hydrogen and the material. The redistribution of the hydrogen between the different binding energy levels is taken into account, too

  1. Subglacial sediment mechanics investigated by computer simulation of granular material

    DEFF Research Database (Denmark)

    Damsgaard, Anders; Egholm, David Lundbek; Tulaczyk, Slawek

    The mechanical properties of subglacial sediments are known to directly influence the stability of ice streams and fast-moving glaciers, but existing models of granular sediment deformation are poorly constrained. In addition, upscaling to generalized mathematical models is difficult due to the m......The mechanical properties of subglacial sediments are known to directly influence the stability of ice streams and fast-moving glaciers, but existing models of granular sediment deformation are poorly constrained. In addition, upscaling to generalized mathematical models is difficult due....... The numerical method is applied to better understand the mechanical properties of the subglacial sediment and its interaction with meltwater. The computational approach allows full experimental control and offers insights into the internal kinematics, stress distribution, and mechanical stability. During...

  2. Mechanical Adaptivity as a Process: Implications to New Materials and Material System Design

    Science.gov (United States)

    2012-08-01

    Mfg / Origami HT Thermal Shape Memory PhotoChem- Mechanical Autonomic Chemo-Mechanical Building Blocks Predictive Models...structure Farkas et al. Chaos 5 1995 Bishop et al. JACS, 2005 Controlling oscillations through medium selection and geometry Controlling...Additive Mfg / Origami HT Thermal Shape Memory PhotoChem- Mechanical Autonomic Chemo-Mechanical Building Blocks Predictive Models

  3. Development and mechanical properties of construction materials from lunar simulants

    Science.gov (United States)

    Desai, Chandra S.

    1990-01-01

    The development of construction materials such as concrete from lunar soils without the use of water requires a different methodology than that used for conventional terrestrial concrete. Currently, this research involves two aspects: (1) liquefaction of lunar simulants with various additives in a furnace so as to produce a construction material like an intermediate ceramic; and (2) cyclic loading of simulant with different initial vacuums and densities with respect to the theoretical maximum densities (TMD). In both cases, bending, triaxial compression, extension, and hydrostatic tests will be performed to define the stress-strain strength response of the resulting materials. In the case of the intermediate ceramic, bending and available multiaxial test devices will be used, while for the compacted case, tests will be performed directly in the new device. The tests will be performed by simulating in situ confining conditions. A preliminary review of high-purity metal is also conducted.

  4. Fracture mechanics of polymer mortar made with recycled raw materials

    Directory of Open Access Journals (Sweden)

    Marco Antonio Godoy Jurumenha

    2010-12-01

    Full Text Available The aim of this work is to show that industrial residues could be used in construction applications so that production costs as well as environmental protection can be improved. The fracture properties of polymer mortar manufactured with recycled materials are investigated to evaluate the materials behaviour to crack propagation. The residues used in this work were spent sand from foundry industry as aggregate, unsaturated polyester resin from polyethylene terephthalate (PET as matrix and polyester textile fibres from garment industry, producing an unique composite material fully from recycled components with low cost. The substitution of fresh by used foundry sand and the insertions of textile fibres contribute to a less brittle behaviour of polymer mortar.

  5. Aging mechanisms in amorphous phase-change materials.

    Science.gov (United States)

    Raty, Jean Yves; Zhang, Wei; Luckas, Jennifer; Chen, Chao; Mazzarello, Riccardo; Bichara, Christophe; Wuttig, Matthias

    2015-06-24

    Aging is a ubiquitous phenomenon in glasses. In the case of phase-change materials, it leads to a drift in the electrical resistance, which hinders the development of ultrahigh density storage devices. Here we elucidate the aging process in amorphous GeTe, a prototypical phase-change material, by advanced numerical simulations, photothermal deflection spectroscopy and impedance spectroscopy experiments. We show that aging is accompanied by a progressive change of the local chemical order towards the crystalline one. Yet, the glass evolves towards a covalent amorphous network with increasing Peierls distortion, whose structural and electronic properties drift away from those of the resonantly bonded crystal. This behaviour sets phase-change materials apart from conventional glass-forming systems, which display the same local structure and bonding in both phases.

  6. Review on advanced composite materials boring mechanism and tools

    Science.gov (United States)

    Shi, Runping; Wang, Chengyong

    2011-05-01

    With the rapid development of aviation and aerospace manufacturing technology, advanced composite materials represented by carbon fibre reinforced plastics (CFRP) and super hybrid composites (fibre/metal plates) are more and more widely applied. The fibres are mainly carbon fibre, boron fibre, Aramid fiber and Sic fibre. The matrixes are resin matrix, metal matrix and ceramic matrix. Advanced composite materials have higher specific strength and higher specific modulus than glass fibre reinforced resin composites of the 1st generation. They are widely used in aviation and aerospace industry due to their high specific strength, high specific modulus, excellent ductility, anticorrosion, heat-insulation, sound-insulation, shock absorption and high&low temperature resistance. They are used for radomes, inlets, airfoils(fuel tank included), flap, aileron, vertical tail, horizontal tail, air brake, skin, baseboards and tails, etc. Its hardness is up to 62~65HRC. The holes are greatly affected by the fibre laminates direction of carbon fibre reinforced composite material due to its anisotropy when drilling in unidirectional laminates. There are burrs, splits at the exit because of stress concentration. Besides there is delamination and the hole is prone to be smaller. Burrs are caused by poor sharpness of cutting edge, delamination, tearing, splitting are caused by the great stress caused by high thrust force. Poorer sharpness of cutting edge leads to lower cutting performance and higher drilling force at the same time. The present research focuses on the interrelation between rotation speed, feed, drill's geometry, drill life, cutting mode, tools material etc. and thrust force. At the same time, holes quantity and holes making difficulty of composites have also increased. It requires high performance drills which won't bring out defects and have long tool life. It has become a trend to develop super hard material tools and tools with special geometry for drilling

  7. Recent advances in the mechanical durability of superhydrophobic materials.

    Science.gov (United States)

    Milionis, Athanasios; Loth, Eric; Bayer, Ilker S

    2016-03-01

    Large majority of superhydrophobic surfaces have very limited mechanical wear robustness and long-term durability. This problem has restricted their utilization in commercial or industrial applications and resulted in extensive research efforts on improving resistance against various types of wear damage. In this review, advances and developments since 2011 in this field will be covered. As such, we summarize progress on fabrication, design and understanding of mechanically durable superhydrophobic surfaces. This includes an overview of recently published diagnostic techniques for probing and demonstrating tribo-mechanical durability against wear and abrasion as well as other effects such as solid/liquid spray or jet impact and underwater resistance. The review is organized in terms of various types of mechanical wear ranging from substrate adhesion, tangential surface abrasion, and dynamic impact to ultrasonic processing underwater. In each of these categories, we highlight the most successful approaches to produce robust surfaces that can maintain their non-wetting state after the wear or abrasive action. Finally, various recommendations for improvement of mechanical wear durability and its quantitative evaluation are discussed along with potential future directions towards more systematic testing methods which will also be acceptable for industry. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. The mechanical spectra of deposited materials by a composite reed vibration method

    International Nuclear Information System (INIS)

    Ying, X.N.; Zhang, L.; Yuan, Y.H.

    2010-01-01

    Recently a composite reed vibration method has been designed to measure the mechanical spectra (complex Young's modulus) of materials from liquid to solid state. The mechanical spectra of materials can be obtained from a composite system consisting of a substrate reed and of materials deposited on it. In this report, two sets of formulas to calculate the mechanical spectra of deposited materials are further analyzed. The proof is given for the previous named 'approximate formulas' (labeled as Formula II). Then the composite reed vibration method can be safely used as an extension of the mechanical spectrum method of the thin solid film. At the same time, some comments are made on previous analytical formulas (labeled as Formula I). At last, more experiments with a small amount of deposited materials are performed. It is found that smaller quantity is more favorable to achieve the intrinsic mechanical spectra of deposited materials.

  9. Formal training program for nuclear material custodians at Hanford Engineering Development Laboratory

    International Nuclear Information System (INIS)

    Scott, D.D.

    1979-01-01

    Hanford Engineering Development Laboratory (HEDL) has established a formal training program for nuclear material (NM) custodians. The program, designed to familiarize the custodian with the fundamental concepts of proper nuclear materials control and accountability, is conducted on a semiannual basis. The program is prepared and presented by the Safeguards and Materials Management Section of HEDL and covers 14 subjects on accountability, documentation, transportation, custodian responsibilities, and the safeguarding of nuclear material

  10. Mechanics of Granular Materials : Constitutive Behavior and Pattern Transformation

    NARCIS (Netherlands)

    Göncü, F.

    2012-01-01

    From pharmaceutical to mining or traveling desert dunes to earthquakes, granular materials are at the heart of many industries and natural phenomena. Improving the efficiency of the machines handling them or, constructing safer buildings requires a critical understanding of their behavior. However,

  11. Modern plastic solar cells : materials, mechanisms and modeling

    NARCIS (Netherlands)

    Chiechi, Ryan C.; Havenith, Remco W.A.; Hummelen, Jan C.; Koster, L. Jan Anton; Loi, Maria A.

    2013-01-01

    We provide a short review of modern 'plastic' solar cells, a broad topic that spans materials science, physics, and chemistry. The aim of this review is to provide a primer for non-experts or researchers in related fields who are curious about this rapidly growing field of interdisciplinary

  12. Advanced Materials Development Program: Ceramic Technology for Advanced Heat Engines program plan, 1983--1993

    Energy Technology Data Exchange (ETDEWEB)

    1990-07-01

    The purpose of the Ceramic Technology for Advanced Heat Engines (CTAHE) Project is the development of an industrial technology base capable of providing reliable and cost-effective high temperature ceramic components for application in advanced heat engines. There is a deliberate emphasis on industrial'' in the purpose statement. The project is intended to support the US ceramic and engine industries by providing the needed ceramic materials technology. The heat engine programs have goals of component development and proof-of-concept. The CTAHE Project is aimed at developing generic basic ceramic technology and does not involve specific engine designs and components. The materials research and development efforts in the CTAHE Project are focused on the needs and general requirements of the advanced gas turbine and low heat rejection diesel engines. The CTAHE Project supports the DOE Office of Transportation Systems' heat engine programs, Advanced Turbine Technology Applications (ATTAP) and Heavy Duty Transport (HDT) by providing the basic technology required for development of reliable and cost-effective ceramic components. The heat engine programs provide the iterative component design, fabrication, and test development logic. 103 refs., 18 figs., 11 tabs.

  13. Implementation of solar-reflective surfaces: Materials and utility programs

    Energy Technology Data Exchange (ETDEWEB)

    Bretz, S.; Akbari, H.; Rosenfeld, A.; Taha, H.

    1992-06-01

    This report focuses on implementation issues for using solar-reflective surfaces to cool urban heat islands, with specific examples for Sacramento, California. Advantages of solar-reflective surfaces for reducing energy use are: (1) they are cost-effective if albedo is increased during routine maintenance; (2) the energy savings coincide with peak demand for power; (3) there are positive effects on environmental quality; and (4) the white materials have a long service life. Important considerations when choosing materials for mitigating heat islands are identified as albedo, emissivity, durability, cost, pollution and appearance. There is a potential for increasing urban albedo in Sacramento by an additional 18%. Of residential roofs, we estimate that asphalt shingle and modified bitumen cover the largest area, and that built-up roofing and modified bitumen cover the largest area of commercial buildings. For all of these roof types, albedo may be increased at the time of re-roofing without any additional cost. When a roof is repaired, a solar-reflective roof coating may be applied to significantly increase albedo and extend the life of the root Although a coating may be cost-effective if applied to a new roof following installation or to an older roof following repair, it is not cost-effective if the coating is applied only to save energy. Solar-reflective pavement may be cost-effective if the albedo change is included in the routine resurfacing schedule. Cost-effective options for producing light-colored pavement may include: (1) asphalt concrete, if white aggregate is locally available; (2) concrete overlays; and (3) newly developed white binders and aggregate. Another option may be hot-rolled asphalt, with white chippings. Utilities could promote solar-reflective surfaces through advertisement, educational programs and cost-sharing of road resurfacing.

  14. Guide for Operational Configuration Management Program including the adjunct programs of design reconstitution and material condition and aging management

    International Nuclear Information System (INIS)

    1993-11-01

    This standard presents program criteria and implementation guidance for an operational configuration management program for DOE nuclear and non-nuclear facilities in the operational phase. Portions of this standard are also useful for other DOE processes, activities, and programs. This Part 1 contains foreword, glossary, acronyms, bibliography, and Chapter 1 on operational configuration management program principles. Appendices are included on configuration management program interfaces, and background material and concepts for operational configuration management

  15. Mechanical properties and material characterization of polysialate structural composites

    Science.gov (United States)

    Foden, Andrew James

    One of the major concerns in using Fiber Reinforced Composites in applications that are subjected to fire is their resistance to high temperature. Some of the fabrics used in FRC, such as carbon, are fire resistant. However, almost all the resins used cannot withstand temperatures higher than 200°C. This dissertation deals with the development and use of a potassium aluminosilicate (GEOPOLYMER) resin that is inorganic and can sustain more than 1000°C. The results presented include the mechanical properties of the unreinforced polysialate matrix in tension, flexure, and compression as well as the strain capacities and surface energy. The mechanical properties of the matrix reinforced with several different fabrics were obtained in flexure, tension, compression and shear. The strength and stiffness of the composite was evaluated for each loading condition. Tests were conducted on unexposed samples as well as samples exposed to temperatures from 200 to 1000°C. Fatigue properties were determined using flexural loading. A study of the effect of several processing variables on the properties of the composite was undertaken to determine the optimum procedure for manufacturing composite plates. The processing variables studied were the curing temperature and pressure, and the post cure drying time required to remove any residual water. The optimum manufacturing conditions were determined using the void content, density, fiber volume fraction, and flexural strength. Analytical models are presented based on both micro and macro mechanical analysis of the composite. Classic laminate theory is used to evaluate the state of the composite as it is being loaded to determine the failure mechanisms. Several failure criteria theories are considered. The analysis is then used to explain the mechanical behavior of the composite that was observed during the experimental study.

  16. Effects of CTR irradiation on the mechanical properties of structural materials

    International Nuclear Information System (INIS)

    Wiffen, F.W.

    1976-11-01

    Mechanical properties of CTR structural materials are important in determining the reliability and economics of fusion power. Furthermore, these properties are significantly affected by the high neutron flux experienced by components in the regions near the plasma of the fusion reactor. In general, irradiation hardens the material and leads to a reduction in ductility. An exception to this is in some complex engineering alloys where either hardening or softening can be observed depending on the alloy and the irradiation conditions. Regardless of this restriction, irradiation usually leads to a reduction in ductility. Available tensile data examined in this paper show that significant ductility reduction can be found for irradiation conditions typical of CTR operation. Consideration of these effects show that extensive work will be needed to fully establish the in-service properties of CTR structures. This information will be used by designers to develop conditions and design philosophies adapted to avoid the most deleterious conditions and minimize stresses on structures on reactor design. The information will also be used as input to alloy development programs with goals of producing materials more resistant to property degradation during irradiation. It is clear that a great deal of additional work will be required both to understand the effect of CTR irradiation on properties and to develop optimal alloys for this application

  17. Residual stress improvement mechanism on metal material by underwater laser irradiation

    International Nuclear Information System (INIS)

    Sano, Yuji; Yoda, Masaki; Mukai, Naruhiko; Obata, Minoru; Kanno, Masanori

    2000-01-01

    Residual stress improvement technology for component surface by underwater pulsed laser irradiation has been developed as a method of preventing stress corrosion cracking (SCC) of core components in nuclear reactors. In order to optimize the laser irradiation conditions based on a complete understanding of the mechanism, the propagation of a shock wave induced by the impulse of laser irradiation and the dynamic response of the irradiated material were analyzed through time-dependent elasto-plastic calculations with a finite element program. The calculated results are compared with the measured results obtained by experiments in which laser pulses with an energy of 200 mJ are focused to a diameter of 0.8 mm on a water-immersed test piece of 20% cold-worked Type 304 austenitic stainless steel to simulate neutron irradiation hardening. A residual compressive stress, which is nearly equivalent to the yield stress of the processed material, remains on the material surface after passage of the shock wave with enough amplitude to induce a permanent strain. Multiple irradiation of laser pulses extends the stress-improved depth to about 1 mm, which would be the limit corresponding to the three-dimensional dispersion effect of the shock wave. (author)

  18. Molecular modeling of polycarbonate materials: Glass transition and mechanical properties

    Science.gov (United States)

    Palczynski, Karol; Wilke, Andreas; Paeschke, Manfred; Dzubiella, Joachim

    2017-09-01

    Linking the experimentally accessible macroscopic properties of thermoplastic polymers to their microscopic static and dynamic properties is a key requirement for targeted material design. Classical molecular dynamics simulations enable us to study the structural and dynamic behavior of molecules on microscopic scales, and statistical physics provides a framework for relating these properties to the macroscopic properties. We take a first step toward creating an automated workflow for the theoretical prediction of thermoplastic material properties by developing an expeditious method for parameterizing a simple yet surprisingly powerful coarse-grained bisphenol-A polycarbonate model which goes beyond previous coarse-grained models and successfully reproduces the thermal expansion behavior, the glass transition temperature as a function of the molecular weight, and several elastic properties.

  19. High mechanical Q-factor measurements on silicon bulk material

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Christian; Nawrodt, Ronny; Heinert, Daniel; Schroeter, Anja; Neubert, Ralf; Thuerk, Matthias; Vodel, Wolfgang; Seidel, Paul [Institut fuer Festkoerperphysik, Helmholtzweg 5, D-07743 Jena (Germany); Tuennermann, Andreas [Institut fuer Angewandte Physik, Albert-Einstein-Strasse 15, D-07745 Jena (Germany)

    2008-07-01

    The direct observation of gravitational waves is one of the biggest challenges in science. Current detectors are limited by different kinds of noise. One of the fundamental noise sources is thermal noise arising from the optical components. One of the most promising attempts to reduce the thermal noise contribution in future detectors will be the use of high Q-factor materials at cryogenic temperatures. Silicon seems to be the most interesting material due to its excellent optical and thermal properties. We present high Q-factor measurements on bulk samples of high purity silicon in a temperature range from 5 to 300 K. The sample dimensions vary between 76.2 mm x 12..75 mm. The Q-factor exceeds 4.10{sup 8} at 6 K. The influence of the crystal orientation, doping and the sample preparation on the Q-factor is discussed.

  20. Estimation of local mechanical properties of highly porous ceramic materials

    Czech Academy of Sciences Publication Activity Database

    Marcián, P.; Majer, Z.; Dlouhý, Ivo; Florian, Z.

    2012-01-01

    Roč. 106, č. 3 (2012), S476-S477 ISSN 0009-2770 R&D Projects: GA ČR(CZ) GA101/09/1821 Institutional support: RVO:68081723 Keywords : cellular structures * tensile test * microCT * image processing * FEM Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 0.453, year: 2012 http://chemicke-listy.cz/docs/full/2012_s3_s405-s441.pdf

  1. PECASE - First Principles Modeling of Mechanics and Chemistry of Materials

    Science.gov (United States)

    2013-01-18

    22-25, 2010) cosponsored by National Academy of Engineering and the Alexander von Humboldt Foundation. Chinese Ministry of Education and Li Ka...Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China, July 18, 2011. Keynote presentation, ASME McMat2011, symposium...San Francisco, April 13-17, 2009. Invited talk, Shanghai Institute of Ceramics , March 10, 2009. Invited talk, TMS 2009 Annual Meeting & Exhibition

  2. Influence of mechanical and chemical degradation on surface gloss of resin composite materials

    NARCIS (Netherlands)

    Ardu, S.; Braut, V.; Uhac, I.; Benbachir, N.; Feilzer, A.J.; Krejci, I.

    2009-01-01

    Purpose: To determine the changes in surface gloss of different composite materials after simulation of mechanical and chemical aging mechanisms. Methods: 36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000- grit SiC abrasive paper, respectively.

  3. 78 FR 67025 - Domestic Requests for Broadcasting Board of Governors Program Materials

    Science.gov (United States)

    2013-11-08

    ... copyrighted materials. List of Subjects in 22 CFR Part 502 Broadcasting, Foreign relations, News media, Public... Agency program materials should be directed to: (a) The Voice of America Office of Public Relations for... from members of the public, organizations, and media, for program materials disseminated by BBG abroad...

  4. 2016 International Conference on Physics and Mechanics of New Materials and Their Applications

    CERN Document Server

    Chang, Shun-Hsyung; Jani, Muaffaq

    2017-01-01

    This book presents 50 selected peer-reviewed reports from the 2016 International Conference on “Physics and Mechanics of New Materials and Their Applications”, PHENMA 2016 (Surabaya, Indonesia, 19–22 July, 2016). The Proceedings are devoted to processing techniques, physics, mechanics, and applications of advanced materials. As such, they examine a wide spectrum of nanostructures, ferroelectric crystals, materials and composites, as well as other promising materials with special properties. They present nanotechnology approaches, modern environmentally friendly piezoelectric and ferromagnetic techniques, and physical and mechanical studies of the structural and physical-mechanical properties of the materials discussed.  Further, a broad range of original mathematical and numerical methods is applied to solve various technological, mechanical and physical problems, which are inte resting for applications. Great attention is devoted to novel devices with high accuracy, longevity and extended possibilitie...

  5. Perinatal programming of neuroendocrine mechanisms connecting feeding behavior and stress

    Directory of Open Access Journals (Sweden)

    Sarah J Spencer

    2013-06-01

    Full Text Available Feeding behavior is closely regulated by neuroendocrine mechanisms that can be influenced by stressful life events. However, the feeding response to stress varies among individuals with some increasing and others decreasing food intake after stress. In addition to the impact of acute lifestyle and genetic backgrounds, the early life environment can have a life-long influence on neuroendocrine mechanisms connecting stress to feeding behavior and may partially explain these opposing feeding responses to stress. In this review I will discuss the perinatal programming of adult hypothalamic stress and feeding circuitry. Specifically I will address how early life (prenatal and postnatal nutrition, early life stress, and the early life hormonal profile can program the hypothalamic-pituitary-adrenal (HPA axis, the endocrine arm of the body’s response to stress long-term and how these changes can, in turn, influence the hypothalamic circuitry responsible for regulating feeding behavior. Thus, over- or under-feeding and / or stressful events during critical windows of early development can alter glucocorticoid (GC regulation of the HPA axis, leading to changes in the GC influence on energy storage and changes in GC negative feedback on HPA axis-derived satiety signals such as corticotropin-releasing-hormone. Furthermore, peripheral hormones controlling satiety, such as leptin and insulin are altered by early life events, and can be influenced, in early life and adulthood, by stress. Importantly, these neuroendocrine signals act as trophic factors during development to stimulate connectivity throughout the hypothalamus. The interplay between these neuroendocrine signals, the perinatal environment, and activation of the stress circuitry in adulthood thus strongly influences feeding behavior and may explain why individuals have unique feeding responses to similar stressors.

  6. Handbook of damage mechanics nano to macro scale for materials and structures

    CERN Document Server

    2015-01-01

    This authoritative reference provides comprehensive coverage of the topics of damage and healing mechanics. Computational modeling of constitutive equations is provided as well as solved examples in engineering applications. A wide range of materials that engineers may encounter are covered, including metals, composites, ceramics, polymers, biomaterials, and nanomaterials. The internationally recognized team of contributors employ a consistent and systematic approach, offering readers a user-friendly reference that is ideal for frequent consultation. Handbook of Damage Mechanics: Nano to Macro Scale for Materials and Structures is ideal for graduate students and faculty, researchers, and professionals in the fields of Mechanical Engineering, Civil Engineering, Aerospace Engineering, Materials Science, and Engineering Mechanics.

  7. Probabilistic Material Strength Degradation Model for Inconel 718 Components Subjected to High Temperature, Mechanical Fatigue, Creep and Thermal Fatigue Effects

    Science.gov (United States)

    Bast, Callie Corinne Scheidt

    1994-01-01

    This thesis presents the on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes four effects that typically reduce lifetime strength: high temperature, mechanical fatigue, creep, and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for four variables, namely, high temperature, mechanical fatigue, creep, and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using the current version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of mechanical fatigue, creep, and thermal fatigue was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.

  8. Basic requirements of mechanical properties for nuclear pressure vessel materials in ASME-BPV code

    International Nuclear Information System (INIS)

    Ning Dong; Yao Weida

    2011-01-01

    The four basic aspects of strengths, ductility, toughness and fatigue strengths can be summarized for overall mechanical properties requirements of materials for nuclear pressure-retaining vessels in ASME-BPV code. These mechanical property indexes involve in the factors of melting, manufacture, delivery conditions, check or recheck for mechanical properties and chemical compositions, etc. and relate to degradation and damage accumulation during the use of materials. This paper specifically accounts for the basic requirements and theoretic basis of mechanical properties for nuclear pressure vessel materials in ASME-BPV code and states the internal mutual relationships among the four aspects of mechanical properties. This paper focuses on putting forward at several problems on mechanical properties of materials that shall be concerned about during design and manufacture for nuclear pressure vessels according to ASME-BPV code. (author)

  9. Fundamental Processes of Coupled Radiation Damage and Mechanical Behavior in Nuclear Fuel Materials for High Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Phillpot, Simon; Tulenko, James

    2011-09-08

    The objective of this work has been to elucidate the relationship among microstructure, radiation damage and mechanical properties for nuclear fuel materials. As representative nuclear materials, we have taken an hcp metal (Mg as a generic metal, and Ti alloys for fast reactors) and UO2 (representing fuel). The degradation of the thermo-mechanical behavior of nuclear fuels under irradiation, both the fissionable material itself and its cladding, is a longstanding issue of critical importance to the nuclear industry. There are experimental indications that nanocrystalline metals and ceramics may be more resistant to radiation damage than their coarse-grained counterparts. The objective of this project look at the effect of microstructure on radiation damage and mechanical behavior in these materials. The approach to be taken was state-of-the-art, large-scale atomic-level simulation. This systematic simulation program of the effects of irradiation on the structure and mechanical properties of polycrystalline Ti and UO2 identified radiation damage mechanisms. Moreover, it will provided important insights into behavior that can be expected in nanocrystalline microstructures and, by extension, nanocomposites. The fundamental insights from this work can be expected to help in the design microstructures that are less susceptible to radiation damage and thermomechanical degradation.

  10. Fundamental Processes of Coupled Radiation Damage and Mechanical Behavior in Nuclear Fuel Materials for High Temperature Reactors

    International Nuclear Information System (INIS)

    Phillpot, Simon; Tulenko, James

    2011-01-01

    The objective of this work has been to elucidate the relationship among microstructure, radiation damage and mechanical properties for nuclear fuel materials. As representative nuclear materials, we have taken an hcp metal (Mg as a generic metal, and Ti alloys for fast reactors) and UO2 (representing fuel). The degradation of the thermo-mechanical behavior of nuclear fuels under irradiation, both the fissionable material itself and its cladding, is a longstanding issue of critical importance to the nuclear industry. There are experimental indications that nanocrystalline metals and ceramics may be more resistant to radiation damage than their coarse-grained counterparts. The objective of this project look at the effect of microstructure on radiation damage and mechanical behavior in these materials. The approach to be taken was state-of-the-art, large-scale atomic-level simulation. This systematic simulation program of the effects of irradiation on the structure and mechanical properties of polycrystalline Ti and UO2 identified radiation damage mechanisms. Moreover, it will provided important insights into behavior that can be expected in nanocrystalline microstructures and, by extension, nanocomposites. The fundamental insights from this work can be expected to help in the design microstructures that are less susceptible to radiation damage and thermomechanical degradation.

  11. Computational Quantum Mechanics for Materials Engineers The EMTO Method and Applications

    CERN Document Server

    Vitos, L

    2007-01-01

    Traditionally, new materials have been developed by empirically correlating their chemical composition, and the manufacturing processes used to form them, with their properties. Until recently, metallurgists have not used quantum theory for practical purposes. However, the development of modern density functional methods means that today, computational quantum mechanics can help engineers to identify and develop novel materials. Computational Quantum Mechanics for Materials Engineers describes new approaches to the modelling of disordered alloys that combine the most efficient quantum-level th

  12. Method of determining elastic and plastic mechanical properties of ceramic materials using spherical indenters

    Science.gov (United States)

    Adler, Thomas A.

    1996-01-01

    The invention pertains a method of determining elastic and plastic mechanical properties of ceramics, intermetallics, metals, plastics and other hard, brittle materials which fracture prior to plastically deforming when loads are applied. Elastic and plastic mechanical properties of ceramic materials are determined using spherical indenters. The method is most useful for measuring and calculating the plastic and elastic deformation of hard, brittle materials with low values of elastic modulus to hardness.

  13. STUDY OF MECHANICAL BEHAVIOR OF TEXTILE REINFORCED COMPOSITE MATERIALS

    Directory of Open Access Journals (Sweden)

    CARLOS ROLANDO RIOS-SOBERANIS

    2012-01-01

    Full Text Available La relación entre la geometría del entramado de las fibras y los mecanismos de fractura bajo cargas de tensión ha sido evaluada para materiales compuestos reforzados con textiles de diferente arquitectura tales como colchoneta (fibras al azar y petatillo (biaxial. Estos materiales están manufacturados empleando como matriz polimérica resina epóxica curada a altas temperaturas. El sistema elegido para este trabajo consiste en resina epóxica bifuncional diglicidil éter de bisfenol A (DGEBA curada con una amina tetrafuncional diaminodifenil sulfona (DDS. Este sistema asegura la obtención de un material rígido transparente con excelentes propiedades mecánicas que permite observar, analizar e identificar el proceso y el progreso del daño generado así como los mecanismos de fractura que conllevan a la ruptura del material. Los resultados demostraron que la arquitectura/geometría de los textiles de refuerzo influye en la generación de sitios de concentración de esfuerzos donde se incrementa la posibilidad de iniciación de fallas y la propagación de grietas.

  14. Modeling Lightning Impact Thermo-Mechanical Damage on Composite Materials

    Science.gov (United States)

    Muñoz, Raúl; Delgado, Sofía; González, Carlos; López-Romano, Bernardo; Wang, De-Yi; LLorca, Javier

    2014-02-01

    Carbon fiber-reinforced polymers, used in primary structures for aircraft due to an excellent strength-to-weight ratio when compared with conventional aluminium alloy counterparts, may nowadays be considered as mature structural materials. Their use has been extended in recent decades, with several aircraft manufacturers delivering fuselages entirely manufactured with carbon composites and using advanced processing technologies. However, one of the main drawbacks of using such composites entails their poor electrical conductivity when compared with aluminium alloy competitors that leads to lightning strikes being considered a significant threat during the service life of the aircraft. Traditionally, this problem was overcome with the use of a protective copper/bronze mesh that added additional weight and reduced the effectiveness of use of the material. Moreover, this traditional sizing method is based on vast experimental campaigns carried out by subjecting composite panels to simulated lightning strike events. While this method has proven its validity, and is necessary for certification of the structure, it may be optimized with the aid provided by physically based numerical models. This paper presents a model based on the finite element method that includes the sources of damage observed in a lightning strike, such as thermal damage caused by Joule overheating and electromagnetic/acoustic pressures induced by the arc around the attachment points. The results of the model are compared with lightning strike experiments carried out in a carbon woven composite.

  15. Helium effect on mechanical property of fusion reactor structural materials

    International Nuclear Information System (INIS)

    Yamamoto, Norikazu; Chuto, Toshinori; Murase, Yoshiharu; Nakagawa, Johsei

    2004-01-01

    High-energy neutrons produced in fusion reactor core caused helium in the structural materials of fusion reactors, such as blankets. We injected alpha particles accelerated by the cyclotron to the samples of martensite steel (9Cr3WVTaB). Equivalent helium doses injected to the sample is estimated to be up to 300 ppm, which were estimated to be equivalent to helium accumulation after the 1-year reactor operation. Creep tests of the samples were made to investigate helium embrittlement. There were no appreciable changes in the relation between the stresses and the rupture time, the minimum creep rate and the applied stress. Grain boundary effect by helium was not observed in ruptured surfaces. Fatigue tests were made for SUS304 samples, which contain helium up to 150 ppm. After 0.05 Hz cyclic stress tests, it was shown that the fatigue lifetime (cycles to rupture and extension to failure) are 1/5 in 150 ppm helium samples compared with no helium samples. The experimental results suggest martensite steel is promising for structural materials of fusion reactors. (Y. Tanaka)

  16. Mechanical coupling for a rotor shaft assembly of dissimilar materials

    Science.gov (United States)

    Shi, Jun [Glastonbury, CT; Bombara, David [New Hartford, CT; Green, Kevin E [Broad Brook, CT; Bird, Connic [Rocky Hill, CT; Holowczak, John [South Windsor, CT

    2009-05-05

    A mechanical coupling for coupling a ceramic disc member to a metallic shaft includes a first wedge clamp and a second wedge clamp. A fastener engages a threaded end of a tie-bolt to sandwich the ceramic disc between the wedge clamps. An axial spring is positioned between the fastener and the second wedge clamp to apply an axial preload along the longitudinal axis. Another coupling utilizes a rotor shaft end of a metallic rotor shaft as one wedge clamp. Still another coupling includes a solid ceramic rotor disc with a multiple of tie-bolts radially displaced from the longitudinal axis to exert the preload on the solid ceramic rotor disc.

  17. Mechanics/heat-transfer relation for particulate materials

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, C.S.; Wang, D.G.; Rahman, K.

    1991-11-01

    The original goal of this study was to try and understand the relationship between the thermal and mechanical properties of particulate flows. Two situations were examined. The first is a study of the effects of simple shear flows, as a embryonic flow type on the apparent thermal conductivity and apparent viscosity of a dry granular flow. The second study involved fluidized beds. The original idea was to try and relate the heat transfer behavior of a fluidized bed to the particle pressure,'' the forces by only the particle phase of the two-phase mixture. (VC)

  18. Mechanics/heat-transfer relation for particulate materials. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, C.S.; Wang, D.G.; Rahman, K.

    1991-11-01

    The original goal of this study was to try and understand the relationship between the thermal and mechanical properties of particulate flows. Two situations were examined. The first is a study of the effects of simple shear flows, as a embryonic flow type on the apparent thermal conductivity and apparent viscosity of a dry granular flow. The second study involved fluidized beds. The original idea was to try and relate the heat transfer behavior of a fluidized bed to the ``particle pressure,`` the forces by only the particle phase of the two-phase mixture. (VC)

  19. Corrosion problems of materials for mechanical, power and chemical engineering

    International Nuclear Information System (INIS)

    Bouska, P.; Cihal, V.; Malik, K.; Vyklicky, M.; Stefec, R.

    1988-01-01

    The proceedings contain 47 contributions, out of which 8 have been inputted in INIS. These are concerned with various corrosion problems of WWER primary circuit components and their testing. The factors affecting the corrosion resistance are analyzed, the simultaneous corrosion action of decontamination of steels is assessed, and the corrosion cracking of special steels is dealt with. The effects of deformation on the corrosion characteristics are examined for steel to be used in fast reactors. The corrosion potentials were measured for various steels. A testing facility for corrosion-mechanical tests is briefly described. (M.D.). 5 figs., 5 tabs., 25 refs

  20. Effect of Organic Material on Mechanical, Hydrological, and Microstructural Properties of Mudstones

    Science.gov (United States)

    Altobelli, M. A.; Reece, J. S.

    2016-12-01

    In this research we analyze the influence of organic material on the mechanical and flow properties of mudstones. We uniformly mix peat, milled and harvested by Bord na Móna from the surface of bogs in Ireland, with natural mudstone from Site C0011 in the Nankai Trough, offshore Japan, obtained during Integrated Ocean Drilling Program Expedition 322. The mudstone had previously been disaggregated into a homogeneous dry powder of clay- and silt-sized particles. The peat is ground and dry-sieved to achieve a similar particle size distribution as the mudstone (mechanical and hydrological processes affected by peat, we prepare dry peat-mudstone mixtures with three different peat concentrations: 0 wt%, 5 wt%, and 10 wt%. Then, these peat - mudstone mixtures are saturated with deionized water at a water content of 109%, formed into stable slurries, and uniaxially compressed to an axial stress of 100 kPa using resedimentation, a method that simulates the natural behavior of deposition and burial in the laboratory under controlled conditions. How the organic material interacts with the mudstone matrix and pore fluid under compression influences the physical properties of the mudstones such as porosity, compressibility, and permeability; all of which are measured in the resedimentation experiments. We will also analyze the microstructural changes as a function of peat concentration using a petrographic microscope and scanning electron microscope. Due to the fibrous and absorbent nature of peat, we anticipate the peat to force tightly packed clay particles in the mudstone apart resulting in a looser microstructure and increased porosity, and thus, a higher compressibility and permeability. Understanding the controls on the mechanical and flow properties of hydrocarbon-bearing, fine-grained formations is crucial for exploration and successful production from hydrocarbon reservoirs. Additionally, this study has large implications for soil water storage and soil amendment to

  1. Defense High-Level Waste Leaching Mechanisms Program. Final report

    International Nuclear Information System (INIS)

    Mendel, J.E.

    1984-08-01

    The Defense High-Level Waste Leaching Mechanisms Program brought six major US laboratories together for three years of cooperative research. The participants reached a consensus that solubility of the leached glass species, particularly solubility in the altered surface layer, is the dominant factor controlling the leaching behavior of defense waste glass in a system in which the flow of leachant is constrained, as it will be in a deep geologic repository. Also, once the surface of waste glass is contacted by ground water, the kinetics of establishing solubility control are relatively rapid. The concentrations of leached species reach saturation, or steady-state concentrations, within a few months to a year at 70 to 90 0 C. Thus, reaction kinetics, which were the main subject of earlier leaching mechanisms studies, are now shown to assume much less importance. The dominance of solubility means that the leach rate is, in fact, directly proportional to ground water flow rate. Doubling the flow rate doubles the effective leach rate. This relationship is expected to obtain in most, if not all, repository situations

  2. Defense High-Level Waste Leaching Mechanisms Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mendel, J.E. (compiler)

    1984-08-01

    The Defense High-Level Waste Leaching Mechanisms Program brought six major US laboratories together for three years of cooperative research. The participants reached a consensus that solubility of the leached glass species, particularly solubility in the altered surface layer, is the dominant factor controlling the leaching behavior of defense waste glass in a system in which the flow of leachant is constrained, as it will be in a deep geologic repository. Also, once the surface of waste glass is contacted by ground water, the kinetics of establishing solubility control are relatively rapid. The concentrations of leached species reach saturation, or steady-state concentrations, within a few months to a year at 70 to 90/sup 0/C. Thus, reaction kinetics, which were the main subject of earlier leaching mechanisms studies, are now shown to assume much less importance. The dominance of solubility means that the leach rate is, in fact, directly proportional to ground water flow rate. Doubling the flow rate doubles the effective leach rate. This relationship is expected to obtain in most, if not all, repository situations.

  3. Some Fundamental Aspects of Mechanics of Nano composite Materials and Structural Members

    International Nuclear Information System (INIS)

    Guz, A.N.; Rushchitsky, J.J.

    2013-01-01

    This paper is devoted to formulation and analysis of fundamental aspects of mechanics of nano composite materials and structural members. These aspects most likely do not exhaust all of the possible fundamental characteristics of mechanics of nano composite materials and structural members, but, nevertheless, they permit to form the skeleton of direction of mechanics in hand. The proposed nine aspects are described and commented briefly.

  4. Mechanisms of sorption of neptunium and technetium on argillaceous materials

    International Nuclear Information System (INIS)

    Hooker, P.J.; West, J.M.; Noy, D.J.

    1986-01-01

    It is of pressing concern to understand the behaviour of radionuclides in the environment and in particular long-lived ones (e.g. Np-237 and Te-99) in argillaceous rocks. Clay formations have been chosen as likely candidates for holding low level radioactive waste repositories and in the event of leakage of radionuclides into the geosphere some knowledge of their fate is required in a far-field safety assessment study. The objectives of this present work were to examine the properties of neptunium and technetium in ground-waters associated with clay-rich materials and to ascertain the variations in sorption of these radionuclides under different environmental conditions and to use the information in a forecast of transport through a clay layer

  5. Multiresolution molecular mechanics: Surface effects in nanoscale materials

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qingcheng, E-mail: qiy9@pitt.edu; To, Albert C., E-mail: albertto@pitt.edu

    2017-05-01

    Surface effects have been observed to contribute significantly to the mechanical response of nanoscale structures. The newly proposed energy-based coarse-grained atomistic method Multiresolution Molecular Mechanics (MMM) (Yang, To (2015), ) is applied to capture surface effect for nanosized structures by designing a surface summation rule SR{sup S} within the framework of MMM. Combined with previously proposed bulk summation rule SR{sup B}, the MMM summation rule SR{sup MMM} is completed. SR{sup S} and SR{sup B} are consistently formed within SR{sup MMM} for general finite element shape functions. Analogous to quadrature rules in finite element method (FEM), the key idea to the good performance of SR{sup MMM} lies in that the order or distribution of energy for coarse-grained atomistic model is mathematically derived such that the number, position and weight of quadrature-type (sampling) atoms can be determined. Mathematically, the derived energy distribution of surface area is different from that of bulk region. Physically, the difference is due to the fact that surface atoms lack neighboring bonding. As such, SR{sup S} and SR{sup B} are employed for surface and bulk domains, respectively. Two- and three-dimensional numerical examples using the respective 4-node bilinear quadrilateral, 8-node quadratic quadrilateral and 8-node hexahedral meshes are employed to verify and validate the proposed approach. It is shown that MMM with SR{sup MMM} accurately captures corner, edge and surface effects with less 0.3% degrees of freedom of the original atomistic system, compared against full atomistic simulation. The effectiveness of SR{sup MMM} with respect to high order element is also demonstrated by employing the 8-node quadratic quadrilateral to solve a beam bending problem considering surface effect. In addition, the introduced sampling error with SR{sup MMM} that is analogous to numerical integration error with quadrature rule in FEM is very small. - Highlights:

  6. Einstein's Materialism and Modern Tests of Quantum Mechanics

    Science.gov (United States)

    Vigier, J. P.

    After a presentation of Einstein's and Bohr's antagonistic point of view on the interpretation of Quantum Mechanics an illustration of their conflicting positions in the particular case of Young's double slit experiment is presented. It is then shown that in their most recent form (i. e. time dependent neutron interferometry) these experiments suggest (if one accepts absolute energymomentum conservation in all individual microprocesses) that Einstein was right in the Bohr-Einstein controversy.Translated AbstractEinsteins Materialismus und heutige Tests der QuantenmechanikNach einer Darstellung von Einsteins und Bohrs antagonistischen Standpunkten in der Interpretation der Quantenmechanik werden ihre widersprüchlichen Positionen im speziellen Fall des Youngschen Doppelspaltexperiments dargestellt. Es wird dann gezeigt, daß diese Experimente in ihrer neuesten Form (d. h. zeitabhängige Neutroneninterferometrie) Einstein in der Bohr-Einsteinkontroverse recht gaben (wenn man absolute Energie-Impulserhaltung bei allen individuellen Mikroprozessen annimmt).

  7. Bedding material affects mechanical thresholds, heat thresholds and texture preference

    Science.gov (United States)

    Moehring, Francie; O’Hara, Crystal L.; Stucky, Cheryl L.

    2015-01-01

    It has long been known that the bedding type animals are housed on can affect breeding behavior and cage environment. Yet little is known about its effects on evoked behavior responses or non-reflexive behaviors. C57BL/6 mice were housed for two weeks on one of five bedding types: Aspen Sani Chips® (standard bedding for our institute), ALPHA-Dri®, Cellu-Dri™, Pure-o’Cel™ or TEK-Fresh. Mice housed on Aspen exhibited the lowest (most sensitive) mechanical thresholds while those on TEK-Fresh exhibited 3-fold higher thresholds. While bedding type had no effect on responses to punctate or dynamic light touch stimuli, TEK-Fresh housed animals exhibited greater responsiveness in a noxious needle assay, than those housed on the other bedding types. Heat sensitivity was also affected by bedding as animals housed on Aspen exhibited the shortest (most sensitive) latencies to withdrawal whereas those housed on TEK-Fresh had the longest (least sensitive) latencies to response. Slight differences between bedding types were also seen in a moderate cold temperature preference assay. A modified tactile conditioned place preference chamber assay revealed that animals preferred TEK-Fresh to Aspen bedding. Bedding type had no effect in a non-reflexive wheel running assay. In both acute (two day) and chronic (5 week) inflammation induced by injection of Complete Freund’s Adjuvant in the hindpaw, mechanical thresholds were reduced in all groups regardless of bedding type, but TEK-Fresh and Pure-o’Cel™ groups exhibited a greater dynamic range between controls and inflamed cohorts than Aspen housed mice. PMID:26456764

  8. Nano Enabled Thermo-Mechanical Materials in Adhesive Joints: A New Paradigm to Materials Functionality (Preprint)

    National Research Council Canada - National Science Library

    Roy, Ajit K; Ganguli, Sabyasachi; Sihn, Sangwook; Qu, Liangti; Dai, Liming

    2006-01-01

    One of the barriers in achieving adequate through-thickness thermal conductivity in composite materials and also in composite joints is the extremely low thermal conductivity of resins (polymer) or adhesives (typically 0.3 W/mK...

  9. Influence of man-made aluminosilicate raw materials on physical and mechanical properties of building materials.

    Science.gov (United States)

    Volodchenko, A. A.; Lesovik, V. S.; Stoletov, A. A.; Glagolev, E. S.; Volodchenko, A. N.; Magomedov, Z. G.

    2018-03-01

    It has been identified that man-made aluminosilicate raw materials represented by clay rock of varied genesis can be used as energy-efficient raw materials to obtain efficient highly-hollow non-autoclaved silicate materials. A technique of structure formation in the conditions of pressureless steam treatment has been offered. Cementing compounds of non- autoclaved silicate materials based on man-made aluminosilicate raw materials possess hydraulic properties that are conditioned by the process of further formation and recrystallization of calcium silicate hydrates, which optimizes the ratio between gellike and crystalline components and densifies the cementing compound structure, which leads to improvement of performance characteristics. Increasing the performance characteristics of the obtained products is possible by changing the molding conditions. For this reason, in order to create high-density material packaging and, as a result, to increase the strength properties of the products, it is reasonable to use higher pressure, under which raw brick is formed, which will facilitate the increase of quality of highly-hollow products.

  10. Failure mechanisms of superhard materials when cutting superalloys

    International Nuclear Information System (INIS)

    Focke, A.E.; Westermann, F.E.; Ermi, A.; Yavelak, J.; Hoch, M.

    1975-01-01

    The present research studies the reasons for the failure of tungsten carbide tools while cutting superalloys. There is a continuous layer of the superalloy in the bottom of the crater which from time to time is torn away locally, taking tungsten carbide crystal with it. Under recommended cutting conditions a plateau (unworn cutting surface) separates the crater from the cutting edge of the tool when cutting AISI 4340. This plateau is totally absent in all cutting of Inconel 718, even in short, two-minute tests. The crater intersects the cutting edge--only a thin wedge of carbide is left which either breaks off or deforms and wears very rapidly. Temperature measurements carried out by use of an infrared detector aimed on the corner of the tungsten carbide indicate at recommended speeds a sharp rise of the temperature at the beginning of the cutting operation, then a steady-state very slow increase as the cutting continues, and finally just before tool failure a very rapid increase in the temperature again. Scanning and replica electron microscopy through the crater and flank face shows that both under the crater and in the back of the cutting edge a fairly deep layer of ''disturbed metal'' exists in which the tungsten carbide grains are much smaller and have much more rounded edges than in the original material. 10 figures, 4 tables

  11. Heat resistance study of basalt fiber material via mechanical tests

    Science.gov (United States)

    Gao, Y. Q.; Jia, C.; Meng, L.; Li, X. H.

    2017-12-01

    This paper focuses on the study of the relationship between the fracture strength of basalt rovings and temperature. Strong stretching performance of the rovings has been tested after the treatment at fixed temperatures but different heating time and then the fracture strength of the rovings exposed to the heating at different temperatures and cooled in different modes investigated. Finally, the fracture strength of the basalt material after the heat treatment was studied. The results showed that the room-temperature strength tends to decrease with an increase of the heat treatment time at 250 °C, but it has the local maximum after 2h heating. And the basalt rovings strength increased after the heat treatment up to 200 °C. It was 16.7 percent higher than the original strength. The strength depends not only on the temperature and duration of the heating, but also on the cooling mode. The value of the strength measured after cold water cooling was less by 6.3% compared with an ambient air cooling mode. The room-temperature breaking strength of the rovings heated at 200 °C and 100 °C for 2 hours each increased by about 14.6% with respect to unpretreated basalt rovings.

  12. Mechanical properties of BixSb2−xTe3 nanostructured thermoelectric material

    International Nuclear Information System (INIS)

    Li, G; Gadelrab, K R; Souier, T; Chiesa, M; Potapov, P L; Chen, G

    2012-01-01

    Research on thermoelectric (TE) materials has been focused on their transport properties in order to maximize their overall performance. Mechanical properties, which are crucial for system reliability, are often overlooked. The recent development of a new class of high-performance, low-dimension thermoelectric materials calls for a better understanding of their mechanical behavior to achieve the desired system reliability. In the present study we investigate the mechanical behavior of nanostructure bulk TE material p-type Bi x Sb 2−x Te 3 by means of nanoindentation and 3D finite element analysis. The Young’s modulus of the material was estimated by the Oliver–Pharr (OP) method and by means of numerically assisted nanoindentation analysis yielding comparable values about 40 GPa. Enhanced hardness and yield strength can be predicted for this nanostructured material. Microstructure is studied and correlation with mechanical properties is discussed. (paper)

  13. 2015 International Conference on Physics and Mechanics of New Materials and their Applications

    CERN Document Server

    Chang, Shun-Hsyung; Topolov, Vitaly

    2016-01-01

    This proceedings volume presents selected and peer reviewed 50 reports of the 2015 International Conference on “Physics and Mechanics of New Materials and Their Applications” (Azov, Russia, 19-22 May, 2015), devoted to 100th Anniversary of the Southern Federal University, Russia. The book presents processing techniques, physics, mechanics, and applications of advanced materials. The book is concentrated on some nanostructures, ferroelectric crystals, materials and composites and other materials with specific properties. In this book are presented nanotechnology approaches, modern piezoelectric techniques, physical and mechanical studies of the structure-sensitive properties of the materials. A wide spectrum of mathematical and numerical methods is applied to the solution of different technological, mechanical and physical problems for applications. Great attention is devoted to novel devices with high accuracy, longevity and extended possibilities to work in a large scale of  temperatures and pressure r...

  14. Mechanical alignment of particles for use in fabricating superconducting and permanent magnetic materials

    International Nuclear Information System (INIS)

    Nellis, W.J.; Maple, M.B.

    1992-01-01

    This patent describes a method of fabricating oriented compacts of superconducting and/or permanent magnetic material. It comprises: providing a base layer of support material, mechanically orienting aligned superconducting or permanently magnetic particles into the desired orientation on the base layer, without mixing the particles with a liquid, optionally covering the particles with a support material, fabricating the base layer and oriented particles assemblage into a desired construct and recovering the resulting fabricated material

  15. STATISTICAL DISTRIBUTION PATTERNS IN MECHANICAL AND FATIGUE PROPERTIES OF METALLIC MATERIALS

    OpenAIRE

    Tatsuo, SAKAI; Masaki, NAKAJIMA; Keiro, TOKAJI; Norihiko, HASEGAWA; Department of Mechanical Engineering, Ritsumeikan University; Department of Mechanical Engineering, Toyota College of Technology; Department of Mechanical Engineering, Gifu University; Department of Mechanical Engineering, Gifu University

    1997-01-01

    Many papers on the statistical aspect of materials strength have been collected and reviewed by The Research Group for Statistical Aspects of Materials Strength.A book of "Statistical Aspects of Materials Strength" was written by this group, and published in 1992.Based on the experimental data compiled in this book, distribution patterns of mechanical properties are systematically surveyed paying an attention to metallic materials.Thus one can obtain the fundamental knowledge for a reliabilit...

  16. Mechanical Properties and Microstructure of Dissimilar Material Welded Joints

    Directory of Open Access Journals (Sweden)

    Ziewiec A.

    2014-10-01

    Full Text Available The paper presents results of the mechanical testing and the microstructure analysis of dissimilar welded joint of the R350HT steel and the high-manganese (Hadfield cast steel using Cr-Ni cast steel spacer. The simulation tests of the welded joint surface deformation were carried out. The macroscopic and microscopic investigation were made using light microscopy (LM and scanning electron microscopy (SEM. Content of the magnetic phase was measured using magnetoscope. The quantitative metallographic investigation was used for assessment of ferrite and martensite contents and X-ray diffraction phase analysis was carried out. The results showed that during cooling of the spacer after welding, the transformation of metastable austenite into martensite proceeded. In addition to work hardening, the phase transformation of austenite into martensite occurs during the process of the superficial deformation of the spacer while simulated exploitation. This leads to a substantial increase of hardness, and at the same time, causes the increase of wear resistance of the welded joints of crossovers.

  17. Mechanism based evaluation of materials behavior and reference curves

    International Nuclear Information System (INIS)

    Toerroenen, K.; Saario, T.; Wallin, K.; Forsten, J.

    1984-01-01

    The safety assessment of nuclear pressure vessels and piping requires a quantitative estimation of defect growth by stable and unstable manner during service. This estimation is essential for determining whether the defect detected during inspection should be repaired or whether the size of the defect even after its expected growth is small enough to leave the integrity of the vessel unaffected. The most important stable defect growth mechanism is that of environmentally assisted cyclic crack growth. Recent results indicate that it is markedly affected by sulfur content and/or manganese sulfide morphology and distribution. This implies that an essential improvement in component safety has been gained by currently applied steelmaking practices, which result in extra low sulfur content, generally below 0.01 wt%, and in round shape and small size of inclusions, through, e.g., calcium treatment, hence considerably reducing the effect of environment on crack growth rate. This further implies that the ASME Section XI reference curves for environmentally accelerated cyclic crack growth are conservative for steels produced by current steelmaking practices. (orig./WL)

  18. Design and fabrication of a cryostat for low temperature mechanical testing for the Mechanical and Materials Engineering group at CERN

    CERN Document Server

    Aviles Santillana, I; Gerardin, A; Guinchard, M; Langeslag, S A E; Sgobba, S

    2015-01-01

    Mechanical testing of materials at low temperatures is one of the cornerstones of the Mechanical and Materials Engineering (MME) group at CERN. A long tradition of more than 20 years and a unique know - how of such tests has been developed with an 18 kN double-walled cryostat. Large campaigns of material qualification have been carried out and the mechanical behaviour of materials at 4 K has been vastly studied in sub - size samples for projects like LEP, LHC and its experiments. With the aim of assessing the mechanical properties of materials of higher strength and/or issued from heavy gauge products for which testing standardized specimens of larger cross section might be more adapted, a new 100 kN cryostat capable of hosting different shapes of normalized samples has been carefully designed and fabricated inhouse together with the associated tooling and measurement instrumentation. It has been conceived to be able to adapt to different test frames both dynamic and static, which will be of paramount importa...

  19. Spontaneous diffusion of an effective skin cancer prevention program through Web-based access to program materials.

    Science.gov (United States)

    Hall, Dawn M; Escoffery, Cam; Nehl, Eric; Glanz, Karen

    2010-11-01

    Little information exists about the diffusion of evidence-based interventions, a process that can occur naturally in organized networks with established communication channels. This article describes the diffusion of an effective skin cancer prevention program called Pool Cool through available Web-based program materials. We used self-administered surveys to collect information from program users about access to and use of Web-based program materials. We analyzed the content of e-mails sent to the official Pool Cool Web site to obtain qualitative information about spontaneous diffusion. Program users were dispersed throughout the United States, most often learning about the program through a Web site (32%), publication (26%), or colleague (19%). Most respondents (86%) reported that their pool provided educational activities at swimming lessons. The Leader's Guide (59%) and lesson cards (50%) were the most commonly downloaded materials, and most respondents reported using these core items sometimes, often, or always. Aluminum sun-safety signs were the least frequently used materials. A limited budget was the most commonly noted obstacle to sun-safety efforts at the pool (85%). Factors supporting sun safety at the pool centered around risk management (85%) and health of the pool staff (78%). Diffusion promotes the use of evidence-based health programs and can occur with and without systematic efforts. Strategies such as providing well-packaged, user-friendly program materials at low or no cost and strategic advertisement of the availability of program materials may increase program use and exposure. Furthermore, highlighting the benefits of the program can motivate potential program users.

  20. Machine assembly with a new material handling mechanism in the sewing machine

    Directory of Open Access Journals (Sweden)

    Umarova Z.M.

    2017-05-01

    Full Text Available the paper presents the dynamic model of the machine assembly with a recommended mechanism for moving material and the definition of the law of rails motion under various system parameters. The author has suggested the solution implemented by the system of differential equations numerically on the PC and the system describing the motion of the machine set. Recommended values ​​of the parameters of elastic links of material transfer mechanism have been obtained. The researcher has developed the methods of kinematic and dynamic analysis of the material transfer mechanism with elastic elements of the sewing machine and has approved the parameters and development of the design.

  1. Contact mechanics at nanometric scale using nanoindentation technique for brittle and ductile materials.

    Science.gov (United States)

    Roa, J J; Rayon, E; Morales, M; Segarra, M

    2012-06-01

    In the last years, Nanoindentation or Instrumented Indentation Technique has become a powerful tool to study the mechanical properties at micro/nanometric scale (commonly known as hardness, elastic modulus and the stress-strain curve). In this review, the different contact mechanisms (elastic and elasto-plastic) are discussed, the recent patents for each mechanism (elastic and elasto-plastic) are summarized in detail, and the basic equations employed to know the mechanical behaviour for brittle and ductile materials are described.

  2. Lawrence Livermore National Laboratory (LLNL) Oxide Material Representation in the Material Identification and Surveillance (MIS) Program, Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Riley, D C; Dodson, K

    2004-06-30

    The Materials Identification and Surveillance (MIS) program was established within the 94-1 R&D Program to confirm the suitability of plutonium-bearing materials for stabilization, packaging, and long-term storage under DOE-STD-3013-2000. Oxide materials from different sites were chemically and physically characterized. The adequacy of the stabilization process parameters of temperature and duration at temperature (950 C and 2 hours) for eliminating chemical reactivity and reducing the moisture content to less than 0.5 weight percent were validated. Studies also include surveillance monitoring to determine the behavior of the oxides and packaging materials under storage conditions. Materials selected for this program were assumed to be representative of the overall inventory for DOE sites. The Quality Assurance section of the DOE-STD-3013-2000 required that each site be responsible for assuring that oxides packaged according to this standard are represented by items in the MIS characterization program. The purpose of this document is to define the path for determining if an individual item is ''represented'' in the MIS Program and to show that oxides being packaged at Lawrence Livermore National Laboratory (LLNL) are considered represented in the MIS program. The methodology outlined in the MIS Representation Document (LA-14016-MS) for demonstrating representation requires concurrence of the MIS working Group (MIS-WG). The signature page on this document provides for the MIS-WG concurrence.

  3. Principal physical mechanisms of material creep resistance and rupture at elevated temperatures

    International Nuclear Information System (INIS)

    Krishtal, M.A.

    1977-01-01

    Mechanisms of creep and long-term failure of refractory materials at different temperatures and stress levels are considered. At high temperatures and low stresses the diffusion (vacancial) mechanism is observed. Temperatures being low and stresses sufficiently high, dislocation mechanism involving avalanche dislocation break-off is manifested. Intermediate conditions provide other mechanisms, i.e. dislocation glide, dislocation climbing, grain-boundary and sub-grain-boundary mechanisms. Quantitative relationships between creep rate and some structural and kinetic parameters are discussed. Account of the creep mechanism is necessary when selecting methods for strengthening of alloys

  4. PREFACE: 10th International Conference on Materials and Mechanisms of Superconductivity (M2S-X)

    Science.gov (United States)

    Greene, L. H.; Zhu, J.-X.; Wang, H.; Meen, J.; Lorenz, B.; Dong, X. L.; dela Cruz, C. R.; Carlson, E.; Bud'ko, S. L.; Bauer, E.; Paglione, J.

    2013-07-01

    The 2012 Materials and Mechanisms of Superconductivity Conference (M2S 2012), which occurs every three years, brought together world experts and young scientists to discuss open questions in the fundamental physics and applications of superconductors, and to disseminate the latest theoretical and experimental research results in superconductors and related novel materials. This conference of 600 participants acted as a valuable training ground in this technologically important area. We focused on key unanswered questions in high-temperature cuprate superconductors, high-temperature iron-based superconductors, topological superconductors, organic superconductors, and heavy-electron superconductors. The discovery of new materials and novel technological applications for electronic devices and for energy transmission and storage was emphasized. There were special sessions on superconductivity and energy, and outreach sessions, and an evening public lecture. There were also junior researcher symposia interspersed within the conference, thus providing an ideal environment for advanced graduate students and postdoctoral researchers to explore the latest theoretical and experimental methods used to investigate challenging questions in the physics of materials as it relates to both fundamental science and technological applications. These proceedings are an archival testament to the excitement in the field and provide a valuable snapshot of the cutting-edge research of 2012. We hope this will be a valuable resource to active researchers in the field as well as an encouraging volume to excite new researchers to the ever-growing, multifaceted field of superconductivity. We thank Bernd Lorenz and his Publications Committee for their tremendously creative and diligent work in putting this volume together. This Conference would not have been possible without the tireless work of our Program Committee, Chaired by Rick Greene and Co-Chaired by Mike Norman. Becky McDuffee, our

  5. A carbon-carbon composite materials development program for fusion energy applications

    International Nuclear Information System (INIS)

    Burchell, T.D.; Eatherly, W.P.; Engle, G.B.; Hollenberg, G.W.

    1992-10-01

    Carbon-carbon composites increasingly are being used for plasma-facing component (PFC) applications in magnetic-confinement plasma-fusion devices. They offer substantial advantages such as enhanced physical and mechanical properties and superior thermal shock resistance compared to the previously favored bulk graphite. Next-generation plasma-fusion reactors, such as the International Thermonuclear Experimental Reactor (ITER) and the Burning Plasma Experiment (BPX), will require advanced carbon-carbon composites possessing extremely high thermal conductivity to manage the anticipated extreme thermal heat loads. This report outlines a program that will facilitate the development of advanced carbon-carbon composites specifically tailored to meet the requirements of ITER and BPX. A strategy for developing the necessary associated design data base is described. Materials property needs, i.e., high thermal conductivity, radiation stability, tritium retention, etc., are assessed and prioritized through a systems analysis of the functional, operational, and component requirements for plasma-facing applications. The current Department of Energy (DOE) Office of Fusion Energy Program on carbon-carbon composites is summarized. Realistic property goals are set based upon our current understanding. The architectures of candidate PFC carbon-carbon composite materials are outlined, and architectural features considered desirable for maximum irradiation stability are described. The European and Japanese carbon-carbon composite development and irradiation programs are described. The Working Group conclusions and recommendations are listed. It is recommended that developmental carbon-carbon composite materials from the commercial sector be procured via request for proposal/request for quotation (RFP/RFQ) as soon as possible

  6. Acquisition of Dynamic Mechanical Analyzer and Stress-Controlled Rheometer for the Mechanical Characterization of Advanced Materials

    Science.gov (United States)

    2017-06-27

    Current efforts aim to refine synthetic methods to achieve high molecular weight polymer and investigate mechanical properties. Figure 4 shows... available in the PCCL. For example, the Sumerlin group is attempting to characterize stimuli-responsive methacrylate networks of varying glass transition...over 100 researchers in advanced polymer materials. Within this, the Polymer Chemistry Characterization Laboratory (PCCL) is a user facility that

  7. Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Liby, Alan L [ORNL; Rogers, Hiram [ORNL

    2013-10-01

    The goal of this activity was to carry out program implementation and technical projects in support of the ARRA-funded Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program of the DOE Advanced Manufacturing Office (AMO) (formerly the Industrial Technologies Program (ITP)). The work was organized into eight projects in four materials areas: strategic materials, structural materials, energy storage and production materials, and advanced/field/transient processing. Strategic materials included work on titanium, magnesium and carbon fiber. Structural materials included work on alumina forming austentic (AFA) and CF8C-Plus steels. The advanced batteries and production materials projects included work on advanced batteries and photovoltaic devices. Advanced/field/transient processing included work on magnetic field processing. Details of the work in the eight projects are available in the project final reports which have been previously submitted.

  8. Ultrastructural changes of cell walls under intense mechanical treatment of selective plant raw material

    International Nuclear Information System (INIS)

    Bychkov, Aleksey L.; Ryabchikova, E.I.; Korolev, K.G.; Lomovsky, O.I.

    2012-01-01

    Structural changes of cell walls under intense mechanical treatment of corn straw and oil-palm fibers were studied by electron and light microscopy. Differences in the character of destruction of plant biomass were revealed, and the dependence of destruction mechanisms on the structure of cell walls and lignin content was demonstrated. We suggest that the high reactivity of the particles of corn straw (about 18% of lignin) after intense mechanical treatment is related to disordering of cell walls and an increase of the surface area, while in the case of oil palm (10% of lignin) the major contribution into an increase in the reactivity is made by an increase of surface area. -- Highlights: ► Structure of cell walls determines the processes of plant materials' destruction. ► Ultrastructure of highly lignified materials strongly disordering by mechanical action. ► Ultrastructure of low-lignified materials is not disordering by mechanical action.

  9. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending December 31, 1982

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1983-05-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division. These activities constitute about one-fourth of the research and development conducted by the division. The major elements of the Materials Sciences Program can be grouped under the areas of (1) structural characterization, (2) high-temperature alloy studies, (3) structural ceramics, and (4) radiation effects

  10. 34 CFR 429.1 - What is the Bilingual Vocational Materials, Methods, and Techniques Program?

    Science.gov (United States)

    2010-07-01

    ... techniques for bilingual vocational training for individuals with limited English proficiency. (Authority..., and Techniques Program? 429.1 Section 429.1 Education Regulations of the Offices of the Department of... MATERIALS, METHODS, AND TECHNIQUES PROGRAM General § 429.1 What is the Bilingual Vocational Materials...

  11. Theoretical analysis of material removal mechanisms in pulsed laser fusion cutting of ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, F [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Varas, F [Dpto Matematica Aplicada II, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Pou, J [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Lusquinos, F [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Boutinguiza, M [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Soto, R [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain); Perez-Amor, M [Dpto FIsica Aplicada, Universidad de Vigo, ETS Ingenieros Industriales, Lagoas-Marcosende 9, 36310 Vigo (Spain)

    2005-02-21

    It is well known that the efficiency of material removal mechanisms has a crucial influence on the performance and quality of the laser cutting process. However, they are very difficult to study since the physical processes and parameters which govern them are quite complicated to observe and measure experimentally. For this reason, the development of theoretical models to analyse the material removal mechanisms is very important for understanding the characteristics and influence of these processes. In this paper, a theoretical model of the pulsed laser fusion cutting of ceramics is presented. The material removal mechanisms from the cutting front are modelled under the assumption that the ceramic material may be, simultaneously, melted and evaporated by the laser radiation. Therefore, three ejection mechanisms are investigated together: ejection of molten material by the assist gas, evaporation of the liquid and ejection of molten material due to the recoil pressure generated by the evaporation from the cutting front. The temporal evolution of the material removal mechanisms and the thickness of the molten layer are solved for several laser pulse modes. Theoretical results are compared with experimental observations to validate the conclusions regarding the influence of frequency and pulse length on the cutting process.

  12. Industry to Education Technical Transfer Program & Composite Materials. Composite Materials Course. Fabrication I Course. Fabrication II Course. Composite Materials Testing Course. Final Report.

    Science.gov (United States)

    Massuda, Rachel

    These four reports provide details of projects to design and implement courses to be offered as requirements for the associate degree program in composites and reinforced plastics technology. The reports describe project activities that led to development of curricula for four courses: composite materials, composite materials fabrication I,…

  13. The US Public Health Service's radioactive materials program

    International Nuclear Information System (INIS)

    Villforth, J.C.

    1996-01-01

    This review concentrates primarily on the U.S. Public Health Service's radiological health programs that are related to the use of radium in medicine. The history of program development is given, with a focus on legal and regulatory aspects. Federal and state cooperative actions are outlined, including congressional radium hearings, National Advisory Committee on Radiation, and Federal Radiation Council rulings. Problems associated with the medical use of radium, such as contamination and disposal, are also described. 30 refs

  14. 2013 International Symposium on Physics and Mechanics of New Materials and Underwater Applications

    CERN Document Server

    Parinov, Ivan; Topolov, Vitaly; Advanced Materials : Physics, Mechanics and Applications

    2014-01-01

    Advanced materials are the basis of modern science and technology. This proceedings volume presents a broad spectrum of studies of novel materials covering their processing techniques, physics, mechanics, and applications. The book is concentrated on nanostructures, ferroelectric crystals, materials and composites, materials for solar cells and also polymeric composites. Nanotechnology approaches, modern piezoelectric techniques and also latest achievements in materials science, condensed matter physics, mechanics of deformable solids and numerical methods are presented. Great attention is devoted to novel devices with high accuracy, longevity and extended possibilities to work in wide temperature and pressure ranges, aggressive media etc. The characteristics of materials and composites with improved properties opening new possibilities of various physical processes, in particular transmission and receipt of signals under water, are described.

  15. 78 FR 19637 - National Organic Program: Notice of Draft Guidance on Classification of Materials and Materials...

    Science.gov (United States)

    2013-04-02

    ... which are specifically allowed in section 205.601 of the USDA organic regulations, as well as materials..., filing of petitions and applications and agency #0;statements of organization and functions are examples... Classification of Materials and Materials for Organic Crop Production AGENCY: Agricultural Marketing Service...

  16. Packaging and transportation of radioactive materials: summary program

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    This document contains summaries or abstracts of reports presented at the Symposium on Packaging and Transportation of Radioactive Materials. Separate indexing has been performed on individual items presented at this conference. (DC)

  17. Advanced organic composite materials for aircraft structures: Future program

    Science.gov (United States)

    1987-01-01

    Revolutionary advances in structural materials have been responsible for revolutionary changes in all fields of engineering. These advances have had and are still having a significant impact on aircraft design and performance. Composites are engineered materials. Their properties are tailored through the use of a mix or blend of different constituents to maximize selected properties of strength and/or stiffness at reduced weights. More than 20 years have passed since the potentials of filamentary composite materials were identified. During the 1970s much lower cost carbon filaments became a reality and gradually designers turned from boron to carbon composites. Despite progress in this field, filamentary composites still have significant unfulfilled potential for increasing aircraft productivity; the rendering of advanced organic composite materials into production aircraft structures was disappointingly slow. Why this is and research and technology development actions that will assist in accelerating the application of advanced organic composites to production aircraft is discussed.

  18. Packaging and transportation of radioactive materials: summary program

    International Nuclear Information System (INIS)

    1978-01-01

    This document contains summaries or abstracts of reports presented at the Symposium on Packaging and Transportation of Radioactive Materials. Separate indexing has been performed on individual items presented at this conference

  19. Enabling novel planetary and terrestrial mechanisms using electroactive materials at the JPL's NDEAA Lab

    Science.gov (United States)

    Bar-Cohen, Yoseph; Sherrit, Stewart; Bao, Xiaoqi; Chang, Zensheu; Lih, Shyh-Shiuh

    2004-01-01

    Increasingly, electroactive materials are used to produce acutators, sensors, displays and other elements of mechanisms and devices. In recognition of the potential of these materials, research at the JPL's NDEAA Lab have led to many novel space and terrestrial applications. This effort involves mostly the use of piezoelectric and electroactive polymers (EAP).

  20. Neutralization of Aerosolized Bio-Agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation Mechanisms

    Science.gov (United States)

    2016-06-01

    Bio -agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation Mechanisms Distribution Statement A. Approved for public...of Cincinnati Project Title: Neutralization of Aerosolized Bio -agents by Filled Nanocomposite Materials through Thermal and Chemical Inactivation...fire ball, where they will not effectively interact with any viable bio -aerosol. 1.1.4. Conclusions Cryo-milling is necessary to achieve a

  1. Mechanical Behavior of Additive Manufactured Layered Materials, Part 2: Stainless Steels

    Science.gov (United States)

    2015-04-30

    materials. Elsevier, Oxford; 2007: 416 -420. [19] Deng, D., Chen, R., Sun, Q. and Li, X. Microstructural study of 17-4PH stainless steel after plasma...1 Mechanical Behavior of Additive Manufactured Layered Materials, Part 2: Stainless Steels * Todd M. Mower † and Michael J. Long M.I.T. Lincoln... stainless steel alloys produced with Direct Metal Laser Sintering (DMLS) was measured and is compared to that of similar conventional materials

  2. A Study on the Interaction Mechanism between Thermal Radiation and Materials

    Institute of Scientific and Technical Information of China (English)

    Dehong XIA; Tao YU; Chuangu WU; Qingqing CHANG; Honglei JIAO

    2005-01-01

    From the viewpoint of field synergy principle and dipole radiation theory, the interaction between the incident thermal radiation wave and materials is analyzed to reveal the mechanism of selective absorption of incident thermal radiation. It is shown that the frequency of the incident thermal radiation and the damping constant of damping oscillators in materials are of vital importance for the thermal radiation properties (reflectivity, absorptivity, transmissivity, etc.) of materials.

  3. Tensile Mechanical Properties and Failure Modes of a Basalt Fiber/Epoxy Resin Composite Material

    OpenAIRE

    He, Jingjing; Shi, Junping; Cao, Xiaoshan; Hu, Yifeng

    2018-01-01

    Uniaxial tensile tests of basalt fiber/epoxy (BF/EP) composite material with four different fiber orientations were conducted under four different fiber volume fractions, and the variations of BF/EP composite material failure modes and tensile mechanical properties were analyzed. The results show that when the fiber volume fraction is constant, the tensile strength, elastic modulus, and limiting strain of BF/EP composite material all decrease with increasing fiber orientation angle. When the ...

  4. Investigation of Resistance to Mechanical Effect of Braille Formed on Different Materials

    Directory of Open Access Journals (Sweden)

    Ingrida VENYTĖ

    2014-06-01

    Full Text Available Qualitative analysis of stresses emerged in paperboard during Braille embossing, using specialized polarimetric equipment, was carried out. Resistance to mechanical effect of Braille dot surfaces, formed with different printing types on different materials (paper, paperboard, polymer, textile, Al foil was investigated. It was determined that Braille dot height change after period mechanical effect is different.

  5. A Postulated Mechanism That Leads to Materialization and Dematerialization of Matter and to Antigravity.

    Science.gov (United States)

    Bearden, Thomas E.

    This document presents a discussion of the postulated mechanism that leads to the materialization and dematerialization of matter and to antigravity. The mechanism also explains why an orbital electron does not radiate energy, in contradiction to classical electromagnetic theory. One of the paradoxes of special relativity is explained. A new model…

  6. Trends and challenges in the mechanics of complex materials: a view

    Science.gov (United States)

    Mariano, Paolo Maria

    2016-01-01

    This article introduces the collection of papers in this issue of the Philosophical Transactions of the Royal Society A and offers a perspective view on the description of the mechanics of material characterized by a prominent influence of small-scale phenomena on the gross mechanical behaviour. PMID:27002073

  7. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending June 30, 1984

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1984-11-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division for the period January 1, 1983, to June 30, 1984. These activities constitute about one-fourth of the research and development conducted by the division. The emphasis of the program can be described as the scientific design of materials. The efforts are directed toward three classes of materials: high-temperature metallic alloys based on intermetallic compounds, structural ceramics, and radiation-resistant alloys

  8. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending June 30, 1984

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J. (comp.)

    1984-11-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division for the period January 1, 1983, to June 30, 1984. These activities constitute about one-fourth of the research and development conducted by the division. The emphasis of the program can be described as the scientific design of materials. The efforts are directed toward three classes of materials: high-temperature metallic alloys based on intermetallic compounds, structural ceramics, and radiation-resistant alloys.

  9. Programming the Assembly of Unnatural Materials with Nucleic Acids

    Science.gov (United States)

    Mirkin, Chad

    Nature directs the assembly of enormously complex and highly functional materials through an encoded class of biomolecules, nucleic acids. The establishment of a similarly programmable code for the construction of synthetic, unnatural materials would allow researchers to impart functionality by precisely positioning all material components. Although it is exceedingly difficult to control the complex interactions between atomic and molecular species in such a manner, interactions between nanoscale components can be directed through the ligands attached to their surface. Our group has shown that nucleic acids can be used as highly programmable surface ligands to control the spacing and symmetry of nanoparticle building blocks in structurally sophisticated and functional materials. These nucleic acids function as programmable ``bonds'' between nanoparticle ``atoms,'' analogous to a nanoscale genetic code for assembling materials. The sequence and length tunability of nucleic acid bonds has allowed us to define a powerful set of design rules for the construction of nanoparticle superlattices with more than 30 unique lattice symmetries, tunable defect structures and interparticle spacings, and several well-defined crystal habits. Further, the nature of the nucleic acid bond enables an additional level of structural control: temporal regulation of dynamic material response to external biomolecular and chemical stimuli. This control allows for the reversible transformation between thermodynamic states with different crystal symmetries, particle stoichiometries, thermal stabilities, and interparticle spacings on demand. Notably, our unique genetic approach affords functional nanoparticle architectures that, among many other applications, can be used to systematically explore and manipulate optoelectronic material properties, such as tunable interparticle plasmonic interactions, microstructure-directed energy emission, and coupled plasmonic and photonic modes.

  10. Metal-ceramic materials. Study and prediction of effective mechanical properties

    International Nuclear Information System (INIS)

    Karakulov, Valerii V.; Smolin, Igor Yu.

    2016-01-01

    Mechanical behavior of stochastic metal-ceramic composite materials was numerically simulated on mesoscopic scale level. Deformation of mesoscopic volumes of composites, whose structure consists of a metal matrix and randomly distributed ceramic inclusions, was numerically simulated. The results of the numerical simulation were used for evaluation of the effective elastic and strength properties of metal-ceramic materials with different parameters of the structure. The values of the effective mechanical properties of investigated materials were obtained, and the character of the dependence of the effective elastic and strength properties on the structure parameters of composites was determined.

  11. Thick film laser induced forward transfer for deposition of thermally and mechanically sensitive materials

    International Nuclear Information System (INIS)

    Kattamis, Nicholas T.; Purnick, Priscilla E.; Weiss, Ron; Arnold, Craig B.

    2007-01-01

    Laser forward transfer processes incorporating thin absorbing films can be used to deposit robust organic and inorganic materials but the deposition of more delicate materials has remained elusive due to contamination and stress induced during the transfer process. Here, we present the approach to high resolution patterning of sensitive materials by incorporating a thick film polymer absorbing layer that is able to dissipate shock energy through mechanical deformation. Multiple mechanisms for transfer as a function of incident laser energy are observed and we show viable and contamination-free deposition of living mammalian embryonic stem cells

  12. Introduction of the Recycling program for Nuclear materials

    International Nuclear Information System (INIS)

    Park, Jae Beom; Shin, Byung Woo; Park, Jae Whan; Park, Soo Jin

    2009-01-01

    The LOF is the abbreviation of Location outside Facilities using in safeguards. IAEA want to control the location using the small nuclear material over the world. The depleted uranium used in Industrial field should be controlled by the Government according to the agreement between the IAEA and the ROK. From 2006, The ROK is managing the locations in the LOF. The detail article governing the locations is on the Location attachment agreed between two bodies. As of end of 2007, The LOF was consisting of 64 locations. Now, A number of Locations are increasing up to 75. The KINAC(Korea Institute of Nuclear Nonproliferation and Control) is controlling the data about the amount of nuclear material in LOF. The KINAC is trying to upgrade the efficiency and accuracy about the data. The KINAC will make a storage house at the underground of head office from 2009. The purpose of the storage system in KINAC is gathering the nuclear material, which is difficult to control by the industries, especially the nuclear material involved in LOF. The final goal for gathering the nuclear materials are recycling to new another machine. I would like to introduce the handling case of the Depleted uranium in their countries. On this paper, I will show 4 countries case briefly

  13. Environmental test program for superconducting materials and devices

    Science.gov (United States)

    Haertling, Gene; Randolph, Henry; Hsi, Chi-Shiung; Verbelyi, Darren

    1991-01-01

    This report is divided into two parts. The first dealing with work involved with Clemson University and the second with the results from Westinghouse/Savannah River. Both areas of work involved low noise, low thermal conductivity superconducting grounding links used in the NASA-sponsored Spectroscopy of the Atmosphere using Far Infrared Emission (SAFIRE) Project. Clemson prepared the links from YBa2Cu3O(7-x) superconductor tape that was mounted on a printed circuit board and encapsulated with epoxy resin. The Clemson program includes temperature vs. resistance, liquid nitrogen immersion, water immersion, thermal cycling, humidity, and radiation testing. The evaluation of the links under a long term environmental test program is described. The Savannah River program includes gamma irradiation, vibration, and long-term evaluation. The progress made in these evaluations is discussed.

  14. 10 CFR 1.41 - Office of Federal and State Materials and Environmental Management Programs.

    Science.gov (United States)

    2010-01-01

    ... Environmental Management Programs. (a) The Office of Federal and State Materials and Environmental Management...) The Office of Federal and State Materials and Environmental Management Programs— (1) Plans and directs... 10 Energy 1 2010-01-01 2010-01-01 false Office of Federal and State Materials and Environmental...

  15. 48 CFR 252.225-7044 - Balance of Payments Program-Construction Material.

    Science.gov (United States)

    2010-10-01

    ... Program-Construction Material. 252.225-7044 Section 252.225-7044 Federal Acquisition Regulations System...—Construction Material. As prescribed in 225.7503(a), use the following clause: Balance of Payments Program—Construction Material (JAN 2009) (a) Definitions. As used in this clause— Commercially available off-the-shelf...

  16. Test methods for the dynamic mechanical properties of polymeric materials. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Baker, G.K.

    1980-06-01

    Various test geometries and procedures for the dynamic mechanical analysis of polymers employing a mechanical spectrometer have been evaluated. The methods and materials included in this work are forced torsional pendulum testing of Kevlar/epoxy laminates and rigid urethane foams, oscillatory parallel plate testing to determine the kinetics of the cure of VCE with Hylene MP, oscillatory compressive testing of B-3223 cellular silicone, and oscillatory tensile testing of Silastic E and single Kevlar filaments. Fundamental dynamic mechanical properties, including the storage and loss moduli and loss tangent of the materials tested, were determined as a function of temperature and sometimes of frequency.

  17. Proceedings of the Seventh Annual Conference on Fossil Energy Materials. Fossil Energy AR and TD Materials Program

    Energy Technology Data Exchange (ETDEWEB)

    Cole, N.C.; Judkins, R.R. [comps.

    1993-07-01

    Objective of the AR&TD Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The 37 papers are arranged into 3 sessions: ceramics, new alloys/intermetallics, and new alloys/advanced austenitics. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  18. Study of the toughening mechanisms in bone and biomimetic hydroxyapatite materials using Raman microprobe spectroscopy.

    Science.gov (United States)

    Pezzotti, Giuseppe; Sakakura, Seiji

    2003-05-01

    A Raman microprobe spectroscopy characterization of microscopic fracture mechanisms is presented for a natural hydroxyapatite material (cortical bovine femur) and two synthetic hydroxyapatite-based materials with biomimetic structures-a hydroxyapatite skeleton interpenetrated with a metallic (silver) or a polymeric (nylon-6) phase. In both the natural and synthetic materials, a conspicuous amount of toughening arose from a microscopic crack-bridging mechanism operated by elasto-plastic stretching of unbroken second-phase ligaments along the crack wake. This mechanism led to a rising R-curve behavior. An additional micromechanism, responsible for stress relaxation at the crack tip, was recognized in the natural bone material and was partly mimicked in the hydroxyapatite/silver composite. This crack-tip mechanism conspicuously enhanced the cortical bone material resistance to fracture initiation. A piezo-spectroscopic technique, based on a microprobe measurement of 980 cm(-1) Raman line of hydroxyapatite, enabled us to quantitatively assess in situ the microscopic stress fields developed during fracture both at the crack tip and along the crack wake. Using the Raman piezo-spectroscopy technique, toughening mechanisms were assessed quantitatively and rationally related to the macroscopic fracture characteristics of hydroxyapatite-based materials. Copyright 2003 Wiley Periodicals, Inc.

  19. Plant materials program. Progress report, June 1980-May 1981

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.; McIlree, A.

    1981-11-01

    This is the first annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, and steam generator tube denting and cracking. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  20. Plant Materials Program: progress June 1981 to May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam geerator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  1. Plant Materials Program: progress June 1981-May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam generator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic area: integranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  2. Mechanical properties of materials used for temporary fixed dentures – in vitro study

    Directory of Open Access Journals (Sweden)

    Celej-Piszcz Elzbieta

    2017-06-01

    Full Text Available Objectives. The objective of the research was to define the mechanical properties of currently marketed temporary filling materials. Methods. Eight temporary filling materials: Boston, Dentalon, Protemp II, Revotek LC, Structure 2, Structure 3, UniFast LC, UniFast Trad were used to make 5 samples each of measurements 2 × 2 × 25 mm, in order to define the flexural strength, and 10 rings each of measurements 2 × 5 mm, in order to carry out the Vickers micro-hardness test. After preparation, the samples were stored in distilled water of temperature of 370°C, for 7 days. Subsequently, flexural strength and Vickers hardness testing was undertaken. Results. Composite temporary materials showed considerably better mechanical properties, both in flexural strength and in Vickers micro-hardness testing. Conclusions. the best mechanical properties, both in terms of flexural strength, as well as Vickers micro-hardness test can be observe among composite materials.

  3. Mechanical property characterization and impact resistance of selected graphite/PEEK composite materials

    Science.gov (United States)

    Baker, Donald J.

    1994-01-01

    To use graphite polyetheretherketone (PEEK) material on highly curved surfaces requires that the material be drapable and easily conformable to the surface. This paper presents the mechanical property characterization and impact resistance results for laminates made from two types of graphite/PEEK materials that will conform to a curved surface. These laminates were made from two different material forms. These forms are: (1) a fabric where each yarn is a co-mingled Celion G30-500 3K graphite fiber and PEEK thermoplastic fiber; and (2) an interleaved material of Celion G30-500 3K graphite fabric interleaved with PEEK thermoplastic film. The experimental results from the fabric laminates are compared with results for laminates made from AS4/PEEK unidirectional tape. The results indicate that the tension and compression moduli for quasi-isotropic and orthotropic laminates made from fabric materials are at least 79 percent of the modulus of equivalent laminates made from tape material. The strength of fabric material laminates is at least 80 percent of laminates made from tape material. The evaluation of fabric material for shear stiffness indicates that a tape material laminate could be replaced by a fabric material laminate and still maintain 89 percent of the shear stiffness of the tape material laminate. The notched quasi-isotropic compression panel failure strength is 42 to 46 percent of the unnotched quasi-isotropic laminate strength. Damage area after impact with 20 ft-lbs of impact energy is larger for the co-mingled panels than for the interleaved panels. The inerleaved panels have less damage than panels made from tape material. Residual compression strength of quasi-isotropic panels after impact of 20 ft-lbs of energy varies between 33 percent of the undamaged quasi-isotropic material strength for the tape material and 38 percent of the undamaged quasi-isotropic material strength for the co-mingled fabric material.

  4. Dependence of the mechanical fracture energy of the polymeric composite material from the mixture of filler fractions

    Directory of Open Access Journals (Sweden)

    E. M. Nurullaev

    2015-01-01

    Full Text Available This paper for the first time presents an equation for calculating the mechanical fracture energy of the polymeric composite material (PCM with regard to the basic formulation parameters. By means of the developed computer program the authors calculated the mechanical fracture energy of the polymer binder of the 3D cross-linked plasticized elastomer filled with multifractional silica. The solution of the integral equation was implemented using the corresponding dependence of stress on relative elongation at uniaxial tension. Engineering application of the theory was considered with respect to asphalt road covering. The authors proposed a generalized dependence of ruptural deformation of the polymer binder from the effective concentration of chemical and physical (intermolecular bonds for calculating the mechanical fracture energy of available and advanced PCMs as filled elastomers.

  5. Nuclear reactor structure materials study (Survey of relevant ISTC programs)

    Energy Technology Data Exchange (ETDEWEB)

    Tocheny, L.V.; Godowski, W. (ISTC-International Science and Technology Center, Moscow (Russian Federation)); Ballesteros, A. (Tecnatom S.A., Materials and Life Management, Madrid (Spain)), e-mail: aballesteros@tecnatom.es; Deffrennes, M.; Hugon, M. (European Commission, DG RTD, Brussels (Belgium))

    2009-07-01

    The international co-operation and programs of ISTC (The International Science and Technology Center) are reviewed in the fields covered by the SMIRT20 Programme. ISTC was created in Moscow in 1994 by Russia, EU, USA, and Japan. Presently, ISTC has 40 member countries (including 27 Member States of the EU), representing the CIS, Europe, Asia, and North America

  6. Quantifying the Mechanical Properties of Materials and the Process of Elastic-Plastic Deformation under External Stress on Material

    Directory of Open Access Journals (Sweden)

    Jan Valíček

    2015-11-01

    Full Text Available The paper solves the problem of the nonexistence of a new method for calculation of dynamics of stress-deformation states of deformation tool-material systems including the construction of stress-strain diagrams. The presented solution focuses on explaining the mechanical behavior of materials after cutting by abrasive waterjet technology (AWJ, especially from the point of view of generated surface topography. AWJ is a flexible tool accurately responding to the mechanical resistance of the material according to the accurately determined shape and roughness of machined surfaces. From the surface topography, it is possible to resolve the transition from ideally elastic to quasi-elastic and plastic stress-strain states. For detecting the surface structure, an optical profilometer was used. Based on the analysis of experimental measurements and the results of analytical studies, a mathematical-physical model was created and an exact method of acquiring the equivalents of mechanical parameters from the topography of surfaces generated by abrasive waterjet cutting and external stress in general was determined. The results of the new approach to the construction of stress-strain diagrams are presented. The calculated values agreed very well with those obtained by a certified laboratory VÚHŽ.

  7. Quantifying the Mechanical Properties of Materials and the Process of Elastic-Plastic Deformation under External Stress on Material

    Science.gov (United States)

    Valíček, Jan; Harničárová, Marta; Öchsner, Andreas; Hutyrová, Zuzana; Kušnerová, Milena; Tozan, Hakan; Michenka, Vít; Šepelák, Vladimír; Mitaľ, Dušan; Zajac, Jozef

    2015-01-01

    The paper solves the problem of the nonexistence of a new method for calculation of dynamics of stress-deformation states of deformation tool-material systems including the construction of stress-strain diagrams. The presented solution focuses on explaining the mechanical behavior of materials after cutting by abrasive waterjet technology (AWJ), especially from the point of view of generated surface topography. AWJ is a flexible tool accurately responding to the mechanical resistance of the material according to the accurately determined shape and roughness of machined surfaces. From the surface topography, it is possible to resolve the transition from ideally elastic to quasi-elastic and plastic stress-strain states. For detecting the surface structure, an optical profilometer was used. Based on the analysis of experimental measurements and the results of analytical studies, a mathematical-physical model was created and an exact method of acquiring the equivalents of mechanical parameters from the topography of surfaces generated by abrasive waterjet cutting and external stress in general was determined. The results of the new approach to the construction of stress-strain diagrams are presented. The calculated values agreed very well with those obtained by a certified laboratory VÚHŽ. PMID:28793645

  8. Computer based ultrasonic system for mechanical and acoustical characterization of materials

    International Nuclear Information System (INIS)

    Rosly Jaafar; Mohd Rozni Mohd Yusof; Khaidzir Hamzah; Md Supar Rohani; Rashdi Shah Ahmad; Amiruddin Shaari

    2001-01-01

    Propagation of both modes of ultrasonic waves velocity i.e. longitudinal (compressional) and transverse (shear), propagating in a material are closely linked with the material's physical and mechanical properties. By measuring both velocity modes, materials' properties such as Young's, bulk and shear moduli, compressibility, Poisson ratio and acoustic impedance can be determined. This paper describes the development of a system that is able to perform the above tasks and is known as Computer Based Ultrasonic for Mechanical and Acoustical Characterisation of Materials (UMC). The system was developed in the NDT Instrumentation and Signal Processing (NDTSP) laboratory of the Physics Department, Universiti Teknologi Malaysia. Measurements were made on four solid samples, namely, glass, copper, mild steel and aluminium. The results of measurements obtained were found to be in good agreement with the values of measurements made using standard methods. The main advantage of using this system over other methods is that single measurement of two ultrasonic velocity modes yields six material's properties. (Author)

  9. ASM Inaugural Lecture 2009: High temperature superconductors: Materials, mechanisms and applications

    International Nuclear Information System (INIS)

    Roslan Abdul Shukor

    2009-01-01

    A surprising variety of new superconducting materials has been discovered in recent years. Many compounds with light elements such as fullerenes, oxides, borides, nitrides, some organic materials and also heavy fermions have been found to superconductor at various temperatures. Hitherto, superconductors have proven to be highly varied in composition but elusive and mysterious. The juxtaposition of superconductivity and magnetism at the nano scale in some of these new materials has paved the way to a rich and exciting new field in condensed matter and materials research. An overview of superconductor research in Malaysian institutions is presented in this paper. Some of the new superconducting materials and their possible mechanisms, conventional and exotic, are presented. The possible role of lattice vibrations in the mechanisms of high temperature superconductivity and the study of this via acoustic methods are discussed. Frozen flux superconductors in a nano magnet-superconductor hybrid system are also discussed. (author)

  10. A hierarchical lattice spring model to simulate the mechanics of 2-D materials-based composites

    Directory of Open Access Journals (Sweden)

    Lucas eBrely

    2015-07-01

    Full Text Available In the field of engineering materials, strength and toughness are typically two mutually exclusive properties. Structural biological materials such as bone, tendon or dentin have resolved this conflict and show unprecedented damage tolerance, toughness and strength levels. The common feature of these materials is their hierarchical heterogeneous structure, which contributes to increased energy dissipation before failure occurring at different scale levels. These structural properties are the key to exceptional bioinspired material mechanical properties, in particular for nanocomposites. Here, we develop a numerical model in order to simulate the mechanisms involved in damage progression and energy dissipation at different size scales in nano- and macro-composites, which depend both on the heterogeneity of the material and on the type of hierarchical structure. Both these aspects have been incorporated into a 2-dimensional model based on a Lattice Spring Model, accounting for geometrical nonlinearities and including statistically-based fracture phenomena. The model has been validated by comparing numerical results to continuum and fracture mechanics results as well as finite elements simulations, and then employed to study how structural aspects impact on hierarchical composite material properties. Results obtained with the numerical code highlight the dependence of stress distributions on matrix properties and reinforcement dispersion, geometry and properties, and how failure of sacrificial elements is directly involved in the damage tolerance of the material. Thanks to the rapidly developing field of nanocomposite manufacture, it is already possible to artificially create materials with multi-scale hierarchical reinforcements. The developed code could be a valuable support in the design and optimization of these advanced materials, drawing inspiration and going beyond biological materials with exceptional mechanical properties.

  11. The US plutonium materials conversion program in Russia

    International Nuclear Information System (INIS)

    Zygmunt, S.J.; Mason, C.F.V.; Hahn, W.K.

    2000-01-01

    Progress has been made in Russia towards the conversion of weapons-grade plutonium (w-Pu) into plutonium oxide (PuO 2 ) suitable for further manufacture into mixed oxide (MOX) fuels. This program was started in 1998 in response to US proliferation concerns and the acknowledged international need to decrease the available weapons-grade Pu. A similar agenda is being followed in the US to address disposition of US surplus weapons-grade Pu. In Russia a conversion process has been selected and a site proposed. This paper discusses the present state of the program in support of this future operating facility that will process up to 5 metric tons of plutonium a year. (authors)

  12. GCFR Fuels and Materials Program at Argonne National Laboratory

    International Nuclear Information System (INIS)

    Neimark, L.A.; Greenberg, S.; Johnson, C.E.; Purohit, A.; Liu, Y.Y.; Rest, J.; Reimann, K.J.; McLennan, G.A.

    1979-01-01

    The F-5 fuel-pin irradiation experiment in EBR-II is a cornerstone of the GCFR program. It is the largest-scale fuel-pin experiment in the present program and will provide data on the performance of pins and a pin-support structure that are prototypic of the GCFR Demonstration Plant. The fuel pins are presently undergoing interim examination after successfully achieving 4.6 at.% burnup. Studies of the thermodynamics and kinetics of the U--Cs--O system, supplemented by analysis of the results of previously irradiated fuel pins, have led to the incorporation of fuel-design modifications in the F-5 experiment to insure adequate performance of the vented fuel. The effect of ribbing, as well as the ribbing process, on the short- and long-term structural performance of fuel-pin cladding is being evaluated via in-reactor and out-of-reactor tests and with the fuel-element modeling code LIFE-GCFR and the finite element program, ADINA

  13. Material Not Categorized As Waste (MNCAW) data report. Radioactive Waste Technical Support Program

    Energy Technology Data Exchange (ETDEWEB)

    Casey, C.; Heath, B.A.

    1992-11-01

    The Department of Energy (DOE), Headquarters, requested all DOE sites storing valuable materials to complete a questionnaire about each material that, if discarded, could be liable to regulation. The Radioactive Waste Technical Support Program entered completed questionnaires into a database and analyzed them for quantities and type of materials stored. This report discusses the data that TSP gathered. The report also discusses problems revealed by the questionnaires and future uses of the data. Appendices contain selected data about material reported.

  14. Radioactive material (RAM) accident/incident data analysis program

    International Nuclear Information System (INIS)

    Emerson, E.L.; McClure, J.D.

    1985-03-01

    This report describes the development of the Radioactive Material Transportation Accident/Incident Data Base (RAM-AIDB), which contains information on the occurrences of transportation accidents and incidents, for radioactive materials (RAM) that are involved in the process of transportation, loading and unloading operation, or temporary storage. These transportation operations are in support of the nuclear fuel cycle for electrical energy generation. This study analyzes in some detail basic accident/incident statistical data, RAM packaging accident response data, and the health effects associated with RAM transport accidents/incidents. This report presents a summary of US RAM transport accident/incident experience for the period 1971 through December 1981. In addition, a sample annual summary of accident/incident experience is presented for the calendar year 1981

  15. Parts, Materials, and Processes Control Program for Expendable Launch Vehicles

    Science.gov (United States)

    2015-07-31

    Resistors 1. All hollow glass or hollow ceramic core devices 2. Unpassivated Nicrome film resistors F-6 3. All hermetic hollow ceramic core film...be the core material, the insulation of the magnet, etc. 2/ Current rating for each winding shall be less than or equal to the rating for a bundle...Instrument Type, General Specification for MIL-PRF-23648 Resistors, Thermal (Thermistor) Insulated , General Specification for MIL-DTL-24308

  16. Development of in-plant real-time materials control: the DYMAC program

    International Nuclear Information System (INIS)

    Augustson, R.H.

    1976-01-01

    LASL is in the process of developing a dynamic materials control program, called DYMAC, to provide the technology for stringent real-time nuclear materials control. The DYMAC program combines hardware and software into four component subsystems: nondestructive assay (NDA), instrumentation, data acquisition, data base management, and real-time accountability. To demonstrate the feasibility of DYMAC, a working real-time materials control system will be installed at the new plutonium facility presently under construction at LASL. Program emphasis is on developing practical solutions to generic problems and communicating those solutions to other installations for use throughout the nuclear fuel cycle

  17. The mechanisms and models of interaction between electrical arc and contact materials

    International Nuclear Information System (INIS)

    Kharin, S.N.

    1999-01-01

    Mechanisms of arc erosion in electrical contacts are different and depends on the conditions of contact separation. The first one, which occurs at low current with relatively slow rate of heat transfer, involves the evaporation of material from the contact surface. The second mechanism can be characterized by the formation of droplets of molten metal caused by high currents and vapor or magnetic pressure on a molten metal pool. However, in certain cases it is impossible to explain the formation of molten metal droplets in terms of pressure only. Therefore a new hypothesis regarding thermo-capillary mechanism of ejection of liquid metal is discussed. This hypothesis is based on the Marangoni effect which is important when the temperature gradient along the liquid contact zone and the temperature dependence of surface tension become significant (tungsten, zirconium, molybdenum etc.). The fourth erosion mechanism is associated with the ejection of solid particles of contact material with distinct crystalline structure during high current pulses of a short duration. It occurs when thermo-elastic processes overcome the mechanical strength. A mathematical model describing each of the four mechanisms of erosion is presented. Temperature fields and erosion characteristics are determined as a function of the commutation regime and the properties of contact materials. The experimental data are discussed in terms of theoretical approach with respect to the solid phase and droplet formation. Dynamics of each type of arc erosion is described, and recommendations for optimal selection of contact material with minimum erosion are given. (author)

  18. Materials with engineered mesoporosity for programmed mass transport

    Science.gov (United States)

    Gough, Dara V.

    Transport in nanostructured materials is of great interest for scientists in various fields, including molecular sequestration, catalysis, artificial photosynthesis and energy storage. This thesis will present work on the transport of molecular and ionic species in mesoporous materials (materials with pore sizes between 2 and 50 nm). Initially, discussion will focus on the synthesis of mesoporous ZnS nanorattles and the size selected mass transport of small molecules through the mesopores. Discussion will then shift of exploration of cation exchange and electroless plating of metals to alter the mesoporous hollow sphere (MHS) materials and properties. The focus of discussion will then shift to the transport of ions into and out of a hierarchically structured gold electrode. Finally, a model gamma-bactiophage was developed to study the electromigration of charged molecules into and out of a confined geometry. A catalytically active biomolecular species was encapsulated within the central cavity of ZnS MHS. Both the activity of the encapsulated enzyme and the size-selective transport through the wall of the MHS were verified through the use of a common fluorogen, hydrogen peroxide, and sodium azide. Additionally, the protection of the enzyme was shown through size-selected blocking of a protease. The mesoporous hollow sphere system introduces size-selectivity to catalyzed chemical reactions; future work may include variations in pore sizes, and pore wall chemical functionalization. The pore size in ZnS mesoporous hollow spheres is controlled between 2.5 and 4.1 nm through swelling of the lyotropic liquid crystal template. The incorporation of a swelling agent is shown to linearly vary the hexagonal lyotropic liquid crystalline phase, which templates the mesopores, while allowing the high fidelity synthesis of mesoporous hollow spheres. Fluorescnently labeled ssDNA was utilized as a probe to explore the change in mesopore permeability afforded by the swollen template

  19. Directory of Certificates of Compliance for Radioactive Materials Packages: Report of NRC Approved Quality Assurance Programs for Radioactive Materials Packages

    International Nuclear Information System (INIS)

    1993-10-01

    This directory contains a Report of NRC Approved Packages (Volume 1), Certificates of Compliance (Volume 2), and a Report of NRC Approved Quality Assurance Programs for Radioactive Materials Packages (Volume 3). The purpose of this directory is to make available a convenient source of information on Quality Assurance Programs and Packagings which have been approved by the US Nuclear Regulatory Commission. Shipments of radioactive material utilizing these packagings must be in accordance with the provisions of 49 CFR section 173.471 and 10 CFR Part 71, as applicable. In satisfying the requirements of Section 71.12, it is the responsibility of the licensees to insure themselves that they have a copy of the current approval and conduct their transportation activities in accordance with an NRC approved quality assurance program

  20. Effects of mechanical properties of thermoplastic materials on the initial force of thermoplastic appliances.

    Science.gov (United States)

    Kohda, Naohisa; Iijima, Masahiro; Muguruma, Takeshi; Brantley, William A; Ahluwalia, Karamdeep S; Mizoguchi, Itaru

    2013-05-01

    To measure the forces delivered by thermoplastic appliances made from three materials and investigate effects of mechanical properties, material thickness, and amount of activation on orthodontic forces. Three thermoplastic materials, Duran (Scheu Dental), Erkodur (Erkodent Erich Kopp GmbH), and Hardcast (Scheu Dental), with two different thicknesses were selected. Values of elastic modulus and hardness were obtained from nanoindentation measurements at 28°C. A custom-fabricated system with a force sensor was employed to obtain measurements of in vitro force delivered by the thermoplastic appliances for 0.5-mm and 1.0-mm activation for bodily tooth movement. Experimental results were subjected to several statistical analyses. Hardcast had significantly lower elastic modulus and hardness than Duran and Erkodur, whose properties were not significantly different. Appliances fabricated from thicker material (0.75 mm or 0.8 mm) always produced significantly greater force than those fabricated from thinner material (0.4 mm or 0.5 mm). Appliances with 1.0-mm activation produced significantly lower force than those with 0.5-mm activation, except for 0.4-mm thick Hardcast appliances. A strong correlation was found between mechanical properties of the thermoplastic materials and force produced by the appliances. Orthodontic forces delivered by thermoplastic appliances depend on the material, thickness, and amount of activation. Mechanical properties of the polymers obtained by nanoindentation testing are predictive of force delivery by these appliances.

  1. Integrating electron microscopy into nanoscience and materials engineering programs

    Science.gov (United States)

    Cormia, Robert D.; Oye, Michael M.; Nguyen, Anh; Skiver, David; Shi, Meng; Torres, Yessica

    2014-10-01

    Preparing an effective workforce in high technology is the goal of both academic and industry training, and has been the engine that drives innovation and product development in the United States for over a century. During the last 50 years, technician training has comprised a combination of two-year academic programs, internships and apprentice training, and extensive On-the-Job Training (OJT). Recently, and especially in Silicon Valley, technicians have four-year college degrees, as well as relevant hands-on training. Characterization in general, and microscopy in particular, is an essential tool in process development, manufacturing and QA/QC, and failure analysis. Training for a broad range of skills and practice is challenging, especially for community colleges. Workforce studies (SRI/Boeing) suggest that even four year colleges often do not provide the relevant training and experience in laboratory skills, especially design of experiments and analysis of data. Companies in high-tech further report difficulty in finding skilled labor, especially with industry specific experience. Foothill College, in partnership with UCSC, SJSU, and NASA-Ames, has developed a microscopy training program embedded in a research laboratory, itself a partnership between university and government, providing hands-on experience in advanced instrumentation, experimental design and problem solving, with real-world context from small business innovators, in an environment called `the collaboratory'. The program builds on AFM-SEM training at Foothill, and provides affordable training in FE-SEM and TEM through a cost recovery model. In addition to instrument and engineering training, the collaboratory also supports academic and personal growth through a multiplayer social network of students, faculty, researchers, and innovators.

  2. Heavy-Section Steel Irradiation Program on irradiation effects in light-water reactor pressure vessel materials

    International Nuclear Information System (INIS)

    Nanstad, R.K.; Corwin, W.R.; Alexander, D.J.; Haggag, F.M.; Iskander, S.K.; McCabe, D.E.; Sokolov, M.A.; Stoller, R.E.

    1995-01-01

    The safety of commercial light-water nuclear plants is highly dependent on the structural integrity of the reactor pressure vessel (RPV). In the absence of radiation damage to the RPV, fracture of the vessel is difficult to postulate. Exposure to high energy neutrons can result in embrittlement of radiation-sensitive RPV materials. The Heavy-Section Steel Irradiation (HSSI) Program at Oak Ridge National Laboratory, sponsored by the US Nuclear Regulatory Commission (USNRC), is assessing the effects of neutron irradiation on RPV material behavior, especially fracture toughness. The results of these and other studies are used by the USNRC in the evaluation of RPV integrity and regulation of overall nuclear plant safety. In assessing the effects of irradiation, prototypic RPV materials are characterized in the unirradiated condition and exposed to radiation under varying conditions. Mechanical property tests are conducted to provide data which can be used in the development of guidelines for structural integrity evaluations, while metallurgical examinations and mechanistic modeling are performed to improve understanding of the mechanisms responsible for embrittlement. The results of these investigations, in conjunction with results from commercial reactor surveillance programs, are used to develop a methodology for the prediction of radiation effects on RPV materials. This irradiation-induced degradation of the materials can be mitigated by thermal annealing, i.e., heating the RPV to a temperature above that of normal operation. Thus, thermal annealing and evaluation of reirradiation behavior are major tasks of the HSSI Program. This paper describes the HSSI Program activities by summarizing some past and recent results, as well as current and planned studies. 30 refs., 8 figs., 1 tab

  3. Interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials: A review.

    Science.gov (United States)

    He, Jie; Yang, Xiaofang; Men, Bin; Wang, Dongsheng

    2016-01-01

    The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals (OH) from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral pH. Hence, it can effectively oxidize refractory organics in water or soils and has become a promising environmentally friendly treatment technology. Due to the complex reaction system, the mechanism behind heterogeneous Fenton reactions remains unresolved but fascinating, and is crucial for understanding Fenton chemistry and the development and application of efficient heterogeneous Fenton technologies. Iron-based materials usually possess high catalytic activity, low cost, negligible toxicity and easy recovery, and are a superior type of heterogeneous Fenton catalysts. Therefore, this article reviews the fundamental but important interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials. OH, hydroperoxyl radicals/superoxide anions (HO2/O2(-)) and high-valent iron are the three main types of reactive oxygen species (ROS), with different oxidation reactivity and selectivity. Based on the mechanisms of ROS generation, the interfacial mechanisms of heterogeneous Fenton systems can be classified as the homogeneous Fenton mechanism induced by surface-leached iron, the heterogeneous catalysis mechanism, and the heterogeneous reaction-induced homogeneous mechanism. Different heterogeneous Fenton systems catalyzed by characteristic iron-based materials are comprehensively reviewed. Finally, related future research directions are also suggested. Copyright © 2015. Published by Elsevier B.V.

  4. Advanced Industrial Materials (AIM) Program: Compilation of project summaries and significant accomplishments, FY 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    In many ways, the Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven ``Vision Industries`` that use about 80% of industrial energy and generated about 90% of industrial wastes. The mission of AIM has, therefore, changed to ``Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.`` Though AIM remains essentially a National Laboratory Program, it is essential that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains reasonably healthy and productive, thanks to the superb investigators and Laboratory Program Managers. This report contains the technical details of some very remarkable work by the best materials scientists and engineers in the world. Subject areas covered are: advanced metals and composites; advanced ceramics and composites; polymers and biobased materials; and new materials and processes.

  5. Fundamental radiation effects studies in the fusion-materials program

    International Nuclear Information System (INIS)

    Doran, D.G.

    1981-10-01

    Some examples of progress being made in DAFS studies are given. The primary parameters in which most damage models are expressed are total displacements per atom (dpa), total helium concentration (appm), and the helium-to-dpa ratio. The concentrations of other transmutation products than helium have assumed significance in certain cases as will be seen below. The number of dpa is generally taken proportional to the damage energy, the total energy deposited in a material, corrected for the fraction dissipated in electronic excitation and ionization

  6. Fissile material disposition program final immobilization form assessment and recommendation

    International Nuclear Information System (INIS)

    Cochran, S.G.; Dunlop, W.H.; Edmunds, T.A.; MacLean, L.M.; Gould, T.H.

    1997-01-01

    Lawrence Livermore National Laboratory (LLNL), in its role as the lead laboratory for the development of plutonium immobilization technologies for the Department of Energy's Office of Fissile Materials Disposition (MD), has been requested by MD to recommend an immobilization technology for the disposition of surplus weapons- usable plutonium. The recommendation and supporting documentation was requested to be provided by September 1, 1997. This report addresses the choice between glass and ceramic technologies for immobilizing plutonium using the can-in-canister approach. Its purpose is to provide a comparative evaluation of the two candidate technologies and to recommend a form based on technical considerations

  7. Mechanical Behaviour of Conventional Materials at Experimental Conditions of Deep Drawing Technological Process

    Science.gov (United States)

    Nikolov, N.; Pashkouleva, D.; Kavardzhikov, V.

    2012-09-01

    The paper deals with experimental investigations on the mechanical behaviour of body-centred-cubic (BCC) and face-centred-cubic (FCC)-conventionally structured sheet metalic-metalic materials under stress-strain conditions of a deep drawing process determined by a coefficient close to the limiting one for Steel 08 and punch diameter of 50 mm. The mechanical characteristics of the investigated materials are identified by one-dimensional tension tests. The materials' responses, as results of identical loading conditions, are described by the change of blank sizes and characteristics of the forming processes. The chosen deformation path ensures obtaining a qualitative steel piece and leads to failures of aluminium and brass blanks. The reported results could be useful for investigations and predictions of the mechanical responses of such type metallic structures applying microscopic instrumented observations and numerical simulations.

  8. Fatigue behaviour of coke drum materials under thermal-mechanical cyclic loading

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2014-01-01

    Full Text Available Coke drums are vertical pressure vessels used in the delayed coking process in petroleum refineries. Significant temperature variation during the delayed coking process causes damage in coke drums in the form of bulging and cracking. There were some studies on the fatigue life estimation for the coke drums, but most of them were based on strain-fatigue life curves at constant temperatures, which do not consider simultaneous cyclic temperature and mechanical loading conditions. In this study, a fatigue testing system is successfully developed to allow performing thermal-mechanical fatigue (TMF test similar to the coke drum loading condition. Two commonly used base and one clad materials of coke drums are then experimentally investigated. In addition, a comparative study between isothermal and TMF lives of these materials is conducted. The experimental findings lead to better understanding of the damage mechanisms occurring in coke drums and more accurate prediction of fatigue life of coke drum materials.

  9. Nuclear-Fuel-Cycle Research Program: availability of geotoxic material

    Energy Technology Data Exchange (ETDEWEB)

    Wachter, B.G.; Kresan, P.L.

    1982-09-01

    This report represents an analog approach to the characterization of the environmental behavior of geotoxic waste materials (toxic material emplaced in the earth's crust) as drawn from literature on the Oklo natural fission reactors and uranium ore deposits relative to radioactive wastes, and hydrothermal metal ore deposits relative to stable toxic wastes. The natural analog data were examined in terms of mobility and immobility of selected radioactive or stable waste elements and are presented in matrix relationship with their prime geochemical variables. A numerical system of ranking those relationships for purposes of hazard-indexing is proposed. Geochemical parameters (especially oxidation/reduction potential) are apparently more potent mobilizers/immobilizers than geological or hydrological conditions in many, if not most, geologic environments for most radioactive waste elements. Heavy metal wastes, by analogy to hydrothermal ore systems and geothermal systems, are less clear in their behavior but similar geochemical patterns do apply. Depth relationships between geochemical variables and waste element behavior show some surprises. It is significantly indicated that for waste isolation, deeper is not necessarily better geochemically. Relatively shallow isolation in host rocks such as shale could offer maximum immobility. This paper provides a geochemical outline for examining analog models as well as a departure point for improved quantification of geological and geochemical indexing of toxic waste hazards.

  10. Nuclear-Fuel-Cycle Research Program: availability of geotoxic material

    International Nuclear Information System (INIS)

    Wachter, B.G.; Kresan, P.L.

    1982-09-01

    This report represents an analog approach to the characterization of the environmental behavior of geotoxic waste materials (toxic material emplaced in the earth's crust) as drawn from literature on the Oklo natural fission reactors and uranium ore deposits relative to radioactive wastes, and hydrothermal metal ore deposits relative to stable toxic wastes. The natural analog data were examined in terms of mobility and immobility of selected radioactive or stable waste elements and are presented in matrix relationship with their prime geochemical variables. A numerical system of ranking those relationships for purposes of hazard-indexing is proposed. Geochemical parameters (especially oxidation/reduction potential) are apparently more potent mobilizers/immobilizers than geological or hydrological conditions in many, if not most, geologic environments for most radioactive waste elements. Heavy metal wastes, by analogy to hydrothermal ore systems and geothermal systems, are less clear in their behavior but similar geochemical patterns do apply. Depth relationships between geochemical variables and waste element behavior show some surprises. It is significantly indicated that for waste isolation, deeper is not necessarily better geochemically. Relatively shallow isolation in host rocks such as shale could offer maximum immobility. This paper provides a geochemical outline for examining analog models as well as a departure point for improved quantification of geological and geochemical indexing of toxic waste hazards

  11. The application of fracture mechanics to the safety assessment of transport casks for radioactive materials

    International Nuclear Information System (INIS)

    Zencker, U.; Mueller, K.; Droste, B.; Roedel, R.; Voelzke, H.

    2004-01-01

    BAM is the German responsible authority for the mechanical and thermal design safety assessment of packages for the transport of radioactive materials. The assessment has to cover the brittle fracture safety proof of package components made of potentially brittle materials. This paper gives a survey of the regulatory and technical requirements for such an assessment according to BAM's new ''Guidelines for the Application of Ductile Cast Iron for Transport and Storage Casks for Radioactive Materials''. Based on these guidelines higher stresses than before can become permissible, but it is necessary to put more effort into the safety assessment procedure. The fundamentals of such a proof with the help of the methods of fracture mechanics are presented. The recommended procedure takes into account the guidelines of the IAEA Advisory Material which are based on the prevention of crack initiation. Examples of BAM's research and safety assessment practices are given. Recommendations for further developments towards package designs with higher acceptable stress levels will be concluded

  12. Data on the physical and mechanical properties of soilcrete materials modified with metakaolin

    Directory of Open Access Journals (Sweden)

    Panagiotis G. Asteris

    2017-08-01

    Full Text Available During the last decades eco-friendly, low-cost, sustainable construction materials for utilization in civil engineering projects have attracted much attention. To this end, soilcretes are non-conventional construction materials produced by mixing natural soil such as natural clay or limestone sand with a hydraulic binder and are recently under detailed and in-depth investigation by many researchers. In this paper the results of the physical and mechanical characteristics of a large set of cylindrical specimens under uniaxial compression, are presented. Specifically, two types of soils such as sand and clay with metakaolin as a mineral additive have been used. This database can be extremely valuable for better understanding of the behavior of soilcrete materials. Furthermore, the results presented herein expected to be of great interest for researchers who deal with the prediction of mechanical properties of materials using soft computing techniques such as artificial intelligence (AI techniques.

  13. The chemo-mechanical effect of cutting fluid on material removal in diamond scribing of silicon

    Science.gov (United States)

    Kumar, Arkadeep; Melkote, Shreyes N.

    2017-07-01

    The mechanical integrity of silicon wafers cut by diamond wire sawing depends on the damage (e.g., micro-cracks) caused by the cutting process. The damage type and extent depends on the material removal mode, i.e., ductile or brittle. This paper investigates the effect of cutting fluid on the mode of material removal in diamond scribing of single crystal silicon, which simulates the material removal process in diamond wire sawing of silicon wafers. We conducted scribing experiments with a diamond tipped indenter in the absence (dry) and in the presence of a water-based cutting fluid. We found that the cutting mode is more ductile when scribing in the presence of cutting fluid compared to dry scribing. We explain the experimental observations by the chemo-mechanical effect of the cutting fluid on silicon, which lowers its hardness and promotes ductile mode material removal.

  14. Data on the physical and mechanical properties of soilcrete materials modified with metakaolin.

    Science.gov (United States)

    Asteris, Panagiotis G; Kolovos, Konstantinos G

    2017-08-01

    During the last decades eco-friendly, low-cost, sustainable construction materials for utilization in civil engineering projects have attracted much attention. To this end, soilcretes are non-conventional construction materials produced by mixing natural soil such as natural clay or limestone sand with a hydraulic binder and are recently under detailed and in-depth investigation by many researchers. In this paper the results of the physical and mechanical characteristics of a large set of cylindrical specimens under uniaxial compression, are presented. Specifically, two types of soils such as sand and clay with metakaolin as a mineral additive have been used. This database can be extremely valuable for better understanding of the behavior of soilcrete materials. Furthermore, the results presented herein expected to be of great interest for researchers who deal with the prediction of mechanical properties of materials using soft computing techniques such as artificial intelligence (AI) techniques.

  15. Inverse methods for the mechanical characterization of materials at high strain rates

    Directory of Open Access Journals (Sweden)

    Casas-Rodriguez J.P.

    2012-08-01

    Full Text Available Mechanical material characterization represents a research challenge. Furthermore, special attention is directed to material characterization at high strain rates as the mechanical properties of some materials are influenced by the rate of loading. Diverse experimental techniques at high strain rates are available, such as the drop-test, the Taylor impact test or the Split Hopkinson pressure bar among others. However, the determination of the material parameters associated to a given mathematical constitutive model from the experimental data is a complex and indirect problem. This paper presents a material characterization methodology to determine the material parameters of a given material constitutive model from a given high strain rate experiment. The characterization methodology is based on an inverse technique in which an inverse problem is formulated and solved as an optimization procedure. The input of the optimization procedure is the characteristic signal from the high strain rate experiment. The output of the procedure is the optimum set of material parameters determined by fitting a numerical simulation to the high strain rate experimental signal.

  16. Comparative study of mechanical properties of direct core build-up materials

    Directory of Open Access Journals (Sweden)

    Girish Kumar

    2015-01-01

    Full Text Available Background and Objectives: The strength greatly influences the selection of core material because core must withstand forces due to mastication and para-function for many years. This study was conducted to evaluate certain mechanical properties of commonly used materials for direct core build-up, including visible light cured composite, polyacid modified composite, resin modified glass ionomer, high copper amalgam, and silver cermet cement. Materials and Methods: All the materials were manipulated according to the manufacturer′s recommendations and standard test specimens were prepared. A universal testing machine at different cross-head speed was used to determine all the four mechanical properties. Mean compressive strength, diametral tensile strength, flexural strength, and elastic modulus with standard deviations were calculated. Multiple comparisons of the materials were also done. Results: Considerable differences in compressive strength, diametral tensile strength, and flexural strength were observed. Visible light cured composite showed relatively high compressive strength, diametral tensile strength, and flexural strength compared with the other tested materials. Amalgam showed the highest value for elastic modulus. Silver cermet showed less value for all the properties except for elastic modulus. Conclusions: Strength is one of the most important criteria for selection of a core material. Stronger materials better resist deformation and fracture provide more equitable stress distribution, greater stability, and greater probability of clinical success.

  17. Environmental Fatigue of Metallic Materials in Nuclear Power Plants - A Review of Korean Test Programs

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Changheul; Jang, Hun; Hong, Jongdae [KAIST, Daejeon (Korea, Republic of); Cho, Hyunchul [Doosan Heavy Industry and Construction, Changwon (Korea, Republic of); Kim, Tae Soon; Lee, Jaegon [KHNP, Daejeon (Korea, Republic of)

    2013-12-15

    Environmental fatigue of the metallic components in light water reactors has been the subject of extensive research and regulatory interest in Korea and abroad. Especially, it was one of the key domestic issues for the license renewal of operating reactors and licensing of advanced reactors during the early 2000s. To deal with the environmental fatigue issue domestically, a systematic test program has been initiated and is still underway. The materials tested were SA508 Gr.1a low alloy steels, 316LN stainless steels, cast stainless steels, and an Alloy 690 and 52M weld. Through tests and subsequent analysis, the mechanisms of reduced low cycle fatigue life have been investigated for those alloys. In addition, the effects of temperature, dissolved oxygen level, and dissolved hydrogen level on low cycle fatigue behaviors have been investigated. In this paper, the test results and key analysis results are briefly summarized. Finally, an on-going test program for hot-bending of 347 stainless steel is introduced.

  18. Results and recommendations from the reactor chemistry and corrosion tasks of the reactor materials program

    International Nuclear Information System (INIS)

    Baumann, E.W.; Ondrejcin, R.S.

    1990-11-01

    Within the general context of extended service life, the Reactor Materials Program was initiated in 1984. This comprehensive program addressed material performance in SRS reactor tanks and the primary coolant or Process Water System (PWS) piping. Three of the eleven tasks concerned moderator quality and corrosion mitigation. Definition and control of the stainless steel aqueous environment is a key factor in corrosion mitigation. The Reactor Materials Program systematically investigated the SRS environment and its effect on crack initiation and propagation in stainless steel, with the objective of improving this environment. The purpose of this report is to summarize the contributions of Tasks 6, 7 and 10 of the Reactor Materials Program to the understanding and control of moderator quality and its relationship to mitigation of stress corrosion cracking

  19. ETV Program Report: Coatings for Wastewater Collection Systems - Standard Cement Materials, Epoxy Coating 4553

    Science.gov (United States)

    The Standard Cement Materials, Inc. Standard Epoxy Coating 4553™ (SEC 4553) epoxy coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Ma...

  20. High Temperature Materials Laboratory User Program: 19th Annual Report, October 1, 2005 - September 30, 2006

    Energy Technology Data Exchange (ETDEWEB)

    Pasto, Arvid [ORNL

    2007-08-01

    Annual Report contains overview of the High Temperature Materials Laboratory User Program and includes selected highlights of user activities for FY2006. Report is submitted to individuals within sponsoring DOE agency and to other interested individuals.

  1. Properties of Mechanically Alloyed W-Ti Materials with Dual Phase Particle Dispersion

    Czech Academy of Sciences Publication Activity Database

    Lukáč, František; Vilémová, Monika; Nevrlá, Barbara; Klečka, Jakub; Chráska, Tomáš; Molnárová, O.

    2017-01-01

    Roč. 7, č. 1 (2017), č. článku 3. ISSN 2075-4701 R&D Projects: GA ČR(CZ) GA15-15609S Institutional support: RVO:61389021 Keywords : tungsten-titanium alloys * mechanical alloying * particle dispersion * pulsed electric current sintering * thermal conductivity * bending strength Subject RIV: JJ - Other Materials OBOR OECD: Materials engineering Impact factor: 1.984, year: 2016

  2. Mechanical Properties of Medium Density Fibreboard Composites Material Using Recycled Rubber and Coconut Coir

    OpenAIRE

    S. Mahzan; A.M. Ahmad Zaidi; M.I. Ghazali; N. Arsat; M.N. M. Hatta

    2010-01-01

    Natural fibre reinforced composite has emerged as highly potential replacement for synthetic fibres. Various natural waste fibres have been adopted for various engineering applications. This paper investigates the mechanical properties of medium density fibreboard composites material fabricated using recycled rubber and coconut coir. The suitability of using recycled rubber and coconut coir as a raw material and polyurethane as a resin in the manufacturer of medium density fibreboard was also...

  3. THE BIODEGRADABILITY AND MECHANICAL STRENGTH OF NUTRITIVE POTS FOR VEGETABLE PLANTING BASED ON LIGNOCELLULOSE COMPOSITE MATERIALS

    OpenAIRE

    Petronela Nechita; Elena Dobrin; Florin Ciolacu; Elena Bobu

    2010-01-01

    Considering the mild degradation strength and the fact that it may be an organic matter reserve for the soil, in the past years lignocellulosic materials have been used as fibrous raw materials in the manufacture of biodegradable nutritive pots for the seedling in vegetable containerized production. This paper analyses the behavior of the nutritive pots made from biodegradable composites for the vegetable seedling production process, focusing on their mechanical strength properties and biodeg...

  4. On the hydro-mechanical behaviour of MX80 bentonite-based materials

    Directory of Open Access Journals (Sweden)

    Yu-Jun Cui

    2017-06-01

    Full Text Available Bentonite-based materials have been considered in many countries as engineered barrier/backfilling materials in deep geological disposal of high-level radioactive waste. During the long period of waste storage, these materials will play an essential role in ensuring the integrity of the storage system that consists of the waste canisters, the engineered barrier/backfill, the retaining structures as well as the geological barrier. Thus, it is essential to well understand the hydro-mechanical behaviours of these bentonite-based materials. This review paper presents the recent advances of knowledge on MX80 bentonite-based materials, in terms of water retention properties, hydraulic behaviour and mechanical behaviour. Emphasis is put on the effect of technological voids and the role of the dry density of bentonite. The swelling anisotropy is also discussed based on the results from swelling tests with measurements of both axial and radial swelling pressures on a sand-bentonite mixture compacted at different densities. Microstructure observation was used to help the interpretation of macroscopic hydro-mechanical behaviour. Also, the evolution of soil microstructure thus the soil density over time is discussed based on the results from mock-up tests. This evolution is essential for understanding the long-term hydro-mechanical behaviour of the engineered barrier/backfill.

  5. Statistical evaluation of low cycle loading curves parameters for structural materials by mechanical characteristics

    International Nuclear Information System (INIS)

    Daunys, Mykolas; Sniuolis, Raimondas

    2006-01-01

    About 300 welded joint materials that are used in nuclear power energy were tested under monotonous tension and low cycle loading in Kaunas University of Technology together with St. Peterburg Central Research Institute of Structural Materials in 1970-2000. The main mechanical, low cycle loading and fracture characteristics of base metals, weld metals and some heat-affected zones of welded joints metals were determined during these experiments. Analytical dependences of low cycle fatigue parameters on mechanical characteristics of structural materials were proposed on the basis of a large number of experimental data, obtained by the same methods and testing equipment. When these dependences are used, expensive low cycle fatigue tests may be omitted and it is possible to compute low cycle loading curves parameters and lifetime for structural materials according to the main mechanical characteristics given in technical manuals. Dependences of low cycle loading curves parameters on mechanical characteristics for several groups of structural materials used in Russian nuclear power energy are obtained by statistical methods and proposed in this paper

  6. Explorations in the application of nanotechnology to improve the mechanical properties of composite materials

    Science.gov (United States)

    Yang, Cheng

    2007-12-01

    This thesis presents the research achievements on the design, preparation, characterization, and analysis of a series of composite materials. By studying the interface interaction of the composite materials using nanotechnology, we developed composite materials that achieve satisfactory mechanical properties in two classes of materials. Durable press (DP) natural textiles are important consumer products usually achieved by erosslinking the molecules in the textiles to achieve long-term wrinkle resistance, which, however, also leads to the simultaneous significant drop of mechanical properties. Herein, a series of polymeric nanoparticl es were investigated, the application of as little as ˜0.14 wt% addition of the nanoparticles improved the mechanical property of the DP cotton fabric by 56% in tearing resistance and 100% in abrasion resistance; the loss in recovery angle is negligible. The author also studied the enzyme-triggered DP treatments of silk fabrics, as a green process method. After the treatment of enzymes, excellent DP property was achieved with improved strain property. Injectable calcium phosphate powder containing acrylic bone cements are widely used in orthopedic surgery to fix artificial prostheses. However, the bending strength is still unsatisfactory. The author modified the surface of the strontium (Sr) containing hydroxyapatite (HA) filler powders with acrylolpamidronate in order to improve the overall mechanical performance of the bone cement composites. By adding 0.25 wt% of acrylolpamidronate to the Sr-HA nanopowders, more than 19% of the bending strength and more than 23% compression strength of the Sr-HA bone cement were improved. Biological evaluations revealed that these bone cement composites were biocompatible and bioactive in cell culture. The results obtained in this thesis work show an effective method to significantly enhance the mechanical properties of composite materials. Different from other available methods, by developing a

  7. Curriculum Development Based on the Big Picture Assessment of the Mechanical Engineering Program

    Science.gov (United States)

    Sabri, Mohd Anas Mohd; Khamis, Nor Kamaliana; Tahir, Mohd Faizal Mat; Wahid, Zaliha; Kamal, Ahmad; Ihsan, Ariffin Mohd; Sulong, Abu Bakar; Abdullah, Shahrum

    2013-01-01

    One of the major concerns of the Engineering Accreditation Council (EAC) is the need for an effective monitoring and evaluation of program outcome domains that can be associated with courses taught under the Mechanical Engineering program. However, an effective monitoring method that can determine the results of each program outcome using Bloom's…

  8. Mechanical and Vibration Testing of Carbon Fiber Composite Material with Embedded Piezoelectric Sensors

    Science.gov (United States)

    Duffy, Kirsten P.; Lerch, Bradley A.; Wilmoth, Nathan G.; Kray, Nicholas; Gemeinhardt, Gregory

    2012-01-01

    Piezoelectric materials have been proposed as a means of decreasing turbomachinery blade vibration either through a passive damping scheme, or as part of an active vibration control system. For polymer matrix fiber composite (PMFC) blades, the piezoelectric elements could be embedded within the blade material, protecting the brittle piezoceramic material from the airflow and from debris. Before implementation of a piezoelectric element within a PMFC blade, the effect on PMFC mechanical properties needs to be understood. This study attempts to determine how the inclusion of a packaged piezoelectric patch affects the material properties of the PMFC. Composite specimens with embedded piezoelectric patches were tested in four-point bending, short beam shear, and flatwise tension configurations. Results show that the embedded piezoelectric material does decrease the strength of the composite material, especially in flatwise tension, attributable to failure at the interface or within the piezoelectric element itself. In addition, the sensing properties of the post-cured embedded piezoelectric materials were tested, and performed as expected. The piezoelectric materials include a non-flexible patch incorporating solid piezoceramic material, and two flexible patch types incorporating piezoelectric fibers. The piezoceramic material used in these patches was Navy Type-II PZT.

  9. A review of mechanical and tribological behaviour of polymer composite materials

    Science.gov (United States)

    Prabhakar, K.; Debnath, S.; Ganesan, R.; Palanikumar, K.

    2018-04-01

    Composite materials are finding increased applications in many industrial applications. A nano-composite is a matrix to which nanosized particles have been incorporated to drastically improve the mechanical performance of the original material. The structural components produced using nano-composites will exhibit a high strength-to-weight ratio. The properties of nano-composites have caused researchers and industries to consider using this material in several fields. Polymer nanocomposites consists of a polymer material having nano-particles or nano-fillers dispersed in the polymer matrix which may be of different shapes with at least one of the dimensions less than 100nm. In this paper, comprehensive review of polymer nanocomposites was done majorly in three different areas. First, mechanical behaviour of polymer nanocomposites which focuses on the mechanical property evaluation such as tensile strength, impact strength and modulus of elasticity based on the different combination of filler materials and nanoparticle inclusion. Second, wear behavior of Polymer composite materials with respect to different impingement angles and variation of filler composition using different processing techniques. Third, tribological (Friction and Wear) behaviour of nanocomposites using various combination of nanoparticle inclusion and time. Finally, it summarized the challenges and prospects of polymer nanocomposites.

  10. Mechanical behavior of a ceramic matrix composite material. M.S. Thesis Final Report

    Science.gov (United States)

    Grosskopf, Paul P.; Duke, John C., Jr.

    1991-01-01

    Monolithic ceramic materials have been used in industry for hundreds of years. These materials have proven their usefulness in many applications, yet, their potential for critical structural applications is limited. The existence of an imperfection in a monolithic ceramic on the order of several microns in size may be critical, resulting in catastrophic failure. To overcome this extreme sensitivity to small material imperfections, reinforced ceramic materials were developed. A ceramic matrix which has been reinforced with continuous fibers is not only less sensitive to microscopic flaws, but is also able to sustain significant damage without suffering catastrophic failure. A borosilicate glass reinforced with several layers of plain weave silicon carbide cloth (Nicalon) was studied. The mechanical testing which was performed included both flexural and tensile loading configurations. This testing was done not only to determine the material properties, but also to initiate a controlled amount of damage within each specimen. Several nondestructive testing techniques, including acousto-ultrasonics (AU), were performed on the specimens periodically during testing. The AU signals were monitored through the use of an IBM compatible personal computer with a high speed data acquisition board. Software was written which manipulates the AU signals in both the time and frequency domains, resulting in quantitative measures of the mechanical response of the material. The measured AU parameters are compared to both the mechanical test results and data from other nondestructive methods including ultrasonic C-scans and penetrant enhanced x ray radiography.

  11. Adjoint-based optimization of mechanical performance in polycrystalline materials and structures through texture control

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Grace [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brown, Judith Alice [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bishop, Joseph E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    The texture of a polycrystalline material refers to the preferred orientation of the grains within the material. In metallic materials, texture can significantly affect the mechanical properties such as elastic moduli, yield stress, strain hardening, and fracture toughness. Recent advances in additive manufacturing of metallic materials offer the possibility in the not too distant future of controlling the spatial variation of texture. In this work, we investigate the advantages, in terms of mechanical performance, of allowing the texture to vary spatially. We use an adjoint-based gradient optimization algorithm within a finite element solver (COMSOL) to optimize several engineering quantities of interest in a simple structure (hole in a plate) and loading (uniaxial tension) condition. As a first step to general texture optimization, we consider the idealized case of a pure fiber texture in which the homogenized properties are transversely isotropic. In this special case, the only spatially varying design variables are the three Euler angles that prescribe the orientation of the homogenized material at each point within the structure. This work paves a new way to design metallic materials for tunable mechanical properties at the microstructure level.

  12. Standard Guide for Recording Mechanical Test Data of Fiber-Reinforced Composite Materials in Databases

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This guide provides a common format for mechanical test data for composite materials for two purposes: (1) to establish data reporting requirements for test methods and ( 2) to provide information for the design of material property databases. This guide should be used in combination with Guide E 1309 which provides similar information to identify the composite material tested. 1.2 These guidelines are specific to mechanical tests of high-modulus fiber-reinforced composite materials. Types of tests considered in this guide include tension, compression, shear, flexure, open/filled hole, bearing, fracture toughness, and fatigue. The ASTM standards for which this guide was developed are listed in . The guidelines may also be useful for additional tests or materials. 1.3 This guide is the second part of a modular approach for which the first part is Guide E 1309. Guide E 1309 serves to identify the material, and this guide serves to describe mechanical testing procedures and variables and to record results....

  13. Classifying the mechanisms of electrochemical shock in ion-intercalation materials

    OpenAIRE

    Woodford, William; Carter, W. Craig; Chiang, Yet-Ming

    2014-01-01

    “Electrochemical shock” – the electrochemical cycling-induced fracture of materials – contributes to impedance growth and performance degradation in ion-intercalation batteries, such as lithium-ion. Using a combination of micromechanical models and acoustic emission experiments, the mechanisms of electrochemical shock are identified, classified, and modeled in targeted model systems with different composition and microstructure. A particular emphasis is placed on mechanical degradation occurr...

  14. Mechanical characterization of sportive tracks made with materials recycled from end-of-life tyres

    OpenAIRE

    Morales-Gámiz, F. J.; Escriba, S.; García-Villena, S. A.; Bermejo, J. M.; Saiz, L.

    2015-01-01

    Congreso celebrado en la Escuela de Arquitectura de la Universidad de Sevilla desde el 24 hasta el 26 de junio de 2015. The European Framework Directive 2008/98/EC on waste established as priority reuse and recycling before other recovery alternatives. In this normative reference, one the main waste flows identified are the end-of-life tyres, as a material whose mechanical properties could provide advantage in the construction of new structures. This paper presents the mechanical character...

  15. Mechanical properties of permeable materials with an organized structure on the base of continuous metal fibers

    International Nuclear Information System (INIS)

    Karpinos, D.M.; Rutkovskij, A.E.; Zorin, V.A.; Ivanchuk, A.A.

    1979-01-01

    The mechanical properties were studied for permeable fibrous materials with an organized structure on the base of continuous metal fibers (from Kh18N9T steel) subjected to preliminary reprocessing volumetric net half-finished products. The effect of geometrical parameters of the net half-finished products and of their orientation in packing are shown to affect the mechanical properties within a wide range of porosities

  16. Russia-U.S. joint program on the safe management of nuclear materials

    International Nuclear Information System (INIS)

    Witmer, F.E.; Krumpe, P.F.; Carlson, D.D.

    1998-06-01

    The Russia-US joint program on the safe management of nuclear materials was initiated to address common technical issues confronting the US and Russia in the management of excess weapons grade nuclear materials. The program was initiated after the 1993 Tomsk-7 accident. This paper provides an update on program activities since 1996. The Fourth US Russia Nuclear Materials Safety Management Workshop was conducted in March 1997. In addition, a number of contracts with Russian Institutes have been placed by Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL). These contracts support research related to the safe disposition of excess plutonium (Pu) and highly enriched uranium (HEU). Topics investigated by Russian scientists under contracts with SNL and LLNL include accident consequence studies, the safety of anion exchange processes, underground isolation of nuclear materials, and the development of materials for the immobilization of excess weapons Pu

  17. PROGRAM ASTEC (ADVANCED SOLAR TURBO ELECTRIC CONCEPT). PART 1. CANDIDATE MATERIALS LABORATORY TESTS

    Science.gov (United States)

    A space power system of the type envisioned by the ASTEC program requires the development of a lightweight solar collector of high reflectance...capable of withstanding the space environment for an extended period. A survey of the environment of interest for ASTEC purposes revealed 4 potential...developed by the solar-collector industry for use in the ASTEC program, and to test the effects of space environment on these materials. Of 6 material

  18. X-ray fluorescence spectroscopy for the elemental analysis of plutonium-bearing materials for the materials disposition program

    International Nuclear Information System (INIS)

    Voit, S.L.; Boerigter, S.T.; Rising, T.L.

    1997-01-01

    The US Fissile Materials Disposition (MD) program will disposition about 50 MT of plutonium in the next century. Both of the alternative technologies for disposition, MOX Fuel and Immobilization require knowledge of the incoming composition to 1--5 wt%. Wavelength Dispersive X-Ray Fluorescence (WDXRF) systems, a common elemental analysis technology with a variety of industrial applications and commercial vendors, can readily achieve this level of characterization. Since much of the excess plutonium will be packaged in a long-term storage container as part of the DOE Environmental Management (DOE-EM) program to stabilize plutonium-bearing materials, the characterization system must be implemented during the packaging process. The authors describe a preliminary design for the integration of the WDXRF system into the packaging system to be used at the Rocky Flats site. The Plutonium Stabilization and Packaging System (PuSPS), coupled with the WDXRF characterization system will provide MD with stabilized plutonium-bearing excess material that can be more readily fed to an immobilization facility. The overall added expense to the MD program of obtaining analytical information after materials have been packaged in long-term storage containers could far exceed the expense of implementing XRF analysis during the packaging process

  19. Fissile material disposition program: Screening of alternate immobilization candidates for disposition of surplus fissile materials

    International Nuclear Information System (INIS)

    Gray, L.W.

    1996-01-01

    With the end of the Cold War, the world faces for the first time the need to dismantle vast numbers of ''excess'' nuclear weapons and dispose of the fissile materials they contain, together with fissile residues in the weapons production complex left over from the production of these weapons. If recently agreed US and Russian reductions are fully implemented, tens of thousands of nuclear weapons, containing a hundred tons or more of plutonium and hundreds of tonnes* of highly enriched uranium (HEU), will no longer be needed worldwide for military purposes. These two materials are the essential ingredients of nuclear weapons, and limits on access to them are the primary technical barrier to prospective proliferants who might desire to acquire a nuclear weapons capability. Theoretically, several kilograms of plutonium, or several times that amount of HEU, is sufficient to make a nuclear explosive device. Therefore, these materials will continue to be a potential threat to humanity for as long as they exist

  20. Mechanisms of material removal and mass transport in focused ion beam nanopore formation

    Energy Technology Data Exchange (ETDEWEB)

    Das, Kallol, E-mail: das7@illinois.edu; Johnson, Harley T., E-mail: htj@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, MC-244, Urbana, Illinois 61801 (United States); Freund, Jonathan B., E-mail: jbfreund@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, MC-244, Urbana, Illinois 61801 (United States); Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, 306 Talbot Laboratory, MC-236, 104 South Wright Street Urbana, Illinois 61801 (United States)

    2015-02-28

    Despite the widespread use of focused ion beam (FIB) processing as a material removal method for applications ranging from electron microscope sample preparation to nanopore processing for DNA sequencing, the basic material removal mechanisms of FIB processing are not well understood. We present the first complete atomistic simulation of high-flux FIB using large-scale parallel molecular dynamics (MD) simulations of nanopore fabrication in freestanding thin films. We focus on the root mechanisms of material removal and rearrangement and describe the role of explosive boiling in forming nanopores. FIB nanopore fabrication is typically understood to occur via sputter erosion. This can be shown to be the case in low flux systems, where individual ion impacts are sufficiently separated in time that they may be considered as independent events. But our detailed MD simulations show that in high flux FIB processing, above a threshold level at which thermal effects become significant, the primary mechanism of material removal changes to a significantly accelerated, thermally dominated process. Under these conditions, the target is heated by the ion beam faster than heat is conducted away by the material, leading quickly to melting, and then continued heating to nearly the material critical temperature. This leads to explosive boiling of the target material with spontaneous bubble formation and coalescence. Mass is rapidly rearranged at the atomistic scale, and material removal occurs orders of magnitude faster than would occur by simple sputtering. While the phenomenology is demonstrated computationally in silicon, it can be expected to occur at lower beam fluxes in other cases where thermal conduction is suppressed due to material properties, geometry, or ambient thermal conditions.

  1. Mechanical and electrochemical characteristics with welding materials in robotic MIG welding of dissimilar Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Jong; Han, Min Su; Woo, Yong Bin [Mokpo Maritime Univ., Mokpo (Korea, Republic of)

    2013-05-15

    In this study, mechanical and electrochemical characteristics with welding material in MIG welded with ROBOT for dissimilar Al alloys were investigated using various experiment methods. The MIG welding by ROBOT with ER5183 and ER5556 for the 5456-H116 and 6061-T6 Al alloy were carried out. The hardness of welding zone was lower than that of base metal. In electrochemical experiment, ER5183 welding material presented excellent characteristics. The yield strength and maximum tensile strength in welding with welding material of ER5183 presented lower value than those of ER5556. The elongation and time-to-fracture showed the opposite results.

  2. Physical and mechanical properties of biobased materials - Starch polylactate and polyhydroxybutyrate

    DEFF Research Database (Denmark)

    Bergenholtz, Karina P.; Nielsen, Per Væggemose; Olsen, M.B.

    2001-01-01

    Commercial and semi-commercial biobased materials (Polylactate, PLA, polyhydroxybutyrate, PHB, wheat starch and corn starch) were investigated. Physical and mechanical characterisation (tensile strength, elongation, tear strength, compression, gas permeability (CO2 and O-2) and water vapour...... permeability (WVP)) was examined. Tests on both films and cups show potential use of these materials for primary food packaging, especially PLA and PHB. An interesting O-2:CO2 permeability ratio (1:7 to 1:12) was seen, which make these materials suitable for packaging of food with high respiration...

  3. Mechanical and thermal stability of graphene and graphene-based materials

    Science.gov (United States)

    Galashev, A. E.; Rakhmanova, O. R.

    2014-10-01

    Graphene has rapidly become one of the most popular materials for technological applications and a test material for new condensed matter ideas. This paper reviews the mechanical properties of graphene and effects related to them that have recently been discovered experimentally or predicted theoretically or by simulation. The topics discussed are of key importance for graphene's use in integrated electronics, thermal materials, and electromechanical devices and include the following: graphene transformation into other sp^2 hybridization forms; stability to stretching and compression; ion-beam-induced structural modifications; how defects and graphene edges affect the electronic properties and thermal stability of graphene and related composites.

  4. Technical challenges in support of the plutonium materials conversion program in Russia

    International Nuclear Information System (INIS)

    Mason, C.F.V.; Zygmunt, S.J.; Hahn, W.K.; James, C.A.; Costa, D.A.; Smith, W.H.; Yarbro, S.L.

    2000-01-01

    The Department of Energy's Plutonium Materials Conversion Program for Russia is designed to assist Russia in defining a path for the destruction of weapons grade plutonium. A similar program is currently defining a program for destruction of US weapons grade plutonium. These two sister programs arose from the September 1998 meeting between President Yeltsin and President Clinton, after which they issued a 'Joint statement of principles for management and disposition of plutonium designated as no longer required for defense purposes'. The US and Russia have each committed to convert 50 metric tons of plutonium from nuclear weapons programs to forms which are unusable for weapons

  5. Parental separation and adult psychological distress: an investigation of material and relational mechanisms.

    Science.gov (United States)

    Lacey, Rebecca E; Bartley, Mel; Pikhart, Hynek; Stafford, Mai; Cable, Noriko

    2014-03-23

    An association between parental separation or divorce occurring in childhood and increased psychological distress in adulthood is well established. However relatively little is known about why this association exists and how the mechanisms might differ for men and women. We investigate why this association exists, focussing on material and relational mechanisms and in particular on the way in which these link across the life course. This study used the 1970 British Cohort Study (n=10,714) to investigate material (through adolescent and adult material disadvantage, and educational attainment) and relational (through parent-child relationship quality and adult partnership status) pathways between parental separation (0-16 years) and psychological distress (30 years). Psychological distress was measured using Rutter's Malaise Inventory. The inter-linkages between these two broad mechanisms across the life course were also investigated. Missing data were multiply imputed by chained equations. Path analysis was used to explicitly model prospectively-collected measures across the life course, therefore methodologically extending previous work. Material and relational pathways partially explained the association between parental separation in childhood and adult psychological distress (indirect effect=33.3% men; 60.0% women). The mechanisms were different for men and women, for instance adult partnership status was found to be more important for men. Material and relational factors were found to interlink across the life course. Mechanisms acting through educational attainment were found to be particularly important. This study begins to disentangle the mechanisms between parental separation in childhood and adult psychological distress. Interventions which aim to support children through education, in particular, are likely to be particularly beneficial for later psychological health.

  6. Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Materials

    Science.gov (United States)

    Richards, Bradley; Zhu, Dongming; Ghosn, Louis; Wadley, Haydn

    2015-01-01

    Development work in Environmental Barrier Coatings (EBCs) for Ceramic Matrix Composites (CMCs) has focused considerably on the identification of materials systems and coating architectures to meet application needs. The evolution of these systems has occurred so quickly that modeling efforts and requisite data for modeling lag considerably behind development. Materials property data exists for many systems in the bulk form, but the effects of deposition on the critical properties of strength and fracture behavior are not well studied. We have plasma sprayed bulk samples of baseline EBC materials (silicon, ytterbium disilicate) and tested the mechanical properties of these materials to elicit differences in strength and toughness. We have also endeavored to assess the mixed-mode fracture resistance, Gc, of silicon in a baseline EBC applied to SiCSiC CMC via four point bend test. These results are compared to previously determined properties of the comparable bulk material.

  7. High-speed infrared imaging for material characterization in experimental mechanics experiments

    Science.gov (United States)

    Gagnon, Marc-André; Marcotte, Frédérick; Lagueux, Philippe; Farley, Vincent; Guyot, Éric; Morton, Vince

    2017-10-01

    Heat transfers are involved in many phenomena such as friction, tensile stress, shear stress and material rupture. Among the challenges encountered during the characterization of such thermal patterns is the need for both high spatial and temporal resolution. Infrared imaging provides information about surface temperature that can be attributed to the stress response of the material and breaking of chemical bounds. In order to illustrate this concept, tensile and shear tests were carried out on steel, aluminum and carbon fiber composite materials and monitored using high-speed (Telops FASTM2K) and high-definition (Telops HD-IR) infrared imaging. Results from split-Hopkinson experiments carried out on a polymer material at high strain-rate are also presented. The results illustrate how high-speed and high-definition infrared imaging in the midwave infrared (MWIR, 3 - 5 μm) spectral range can provide detailed information about the thermal properties of materials undergoing mechanical testing.

  8. Plutonium working reference materials for the NDA PDP program

    International Nuclear Information System (INIS)

    Marshall, R.; Foley, M.; McCullough, L.; Vance, D.

    1995-01-01

    Sixty-three QC standards, termed Working Reference Materials (WRMs) are being fabricated at Los Alamos for the Non-destructive Waste Assay Performance Development Plan. The WRMs require Pu and Am distributed uniformly in a low density matrix. A silicone rubber matrix initially specified has been changed to a packed, diatomaceous earth (DE) matrix to facilitate Pu-DE uniformity and minimize gas generation and WRM pressurization. Uniformity and separation stability was demonstrated with iron powder-DE mixtures. To meet the rigorous quality objectives on the mass of Pu and Am for each WRM, a uniform, stable batch of PuO2 with relatively high Am-241 content was prepared by blending, calcining, and screening. Multiple sample analyses demonstrated the PuO2 to be highly uniform and established that tight Pu and Am assay and Pu isotopic analysis precision requirements were met. Test blends were prepared and tested to successfully demonstrate Pu uniformity, freedom from PuO2 clumping, and acceptable alpha-neutron generation rates. Blends of PuO2-DE were prepared individually for each WRM; all 63 blends have been prepared. After loading and packing the blends into zircalloy cylinders, the air atmosphere will be replaced with helium and end caps inserted and welded. Following decontamination and leak checking, the cylinders will be loaded into secondary zircalloy cylinders and sealed with welded end caps

  9. Bleed water testing program for controlled low strength material

    International Nuclear Information System (INIS)

    Langton, C.A.

    1996-01-01

    Bleed water measurements for two Controlled Low Strength Material (CLSM) mixes were conducted to provide engineering data for the Tank 20F closure activities. CLSM Mix 1 contained 150 pounds of cement per cubic yard whereas CLSM Mix 2 contained 50 pounds per cub yard. SRS currently used CLSM Mix 2 for various applications. Bleed water percentages and generation rates were measured along with flow and compressive strength. This information will be used to select a mix design for the Tank 20F closure activities and to establish the engineering requirements, such as, lift height, time required between lifts and quantity of bleed water to be removed from the tank during the placement activities. Mix 1 is recommended for placement within Tank 20F because it has better flow characteristics, less segregation, lower percentage of bleed water and slightly higher strength. Optimization of Mix 1 was beyond the scope of this study. However, further testing of thickening additives, such as clays (bentonite), sodium silicate or fine silicas maybe useful for decreasing or eliminating bleed water

  10. Space and Missile Systems Center Standard: Parts, Materials, and Processes Control Program for Space Vehicles

    Science.gov (United States)

    2013-04-12

    preparation , implementation, and operation of a Parts, Materials, and Processes (PMP) control program for use during the design, development...Processes List CDR Critical Design Review CDRL Contract Data Requirements List CMOS Complementary Metal Oxide Semiconductor CONOPS Concept of Operations...Failure Review Board GFE Government Furnished Equipment GIDEP Government Industry Data Exchange Program HBT Heterojunction Bipolar Transistor IPT

  11. Materials Sciences programs, fiscal year 1978: Office of Basic Energy Services

    International Nuclear Information System (INIS)

    1978-09-01

    A compilation and index are provided of the the DOE Materials Sciences Division programs. This compilation is intended for use by administrators, managers, and scientists to help coordinate research and as an aid in selecting new programs. The report is divided into Sections A and B, listing all the projects, Section C, a summary of funding levels, and Section D, an index

  12. Materials Sciences Programs. Fiscal Year 1980, Office of Basic Energy Sciences

    International Nuclear Information System (INIS)

    1980-09-01

    This report provides a convenient compilation index of the DOE Materials Sciences Division programs. This compilation is intended for use by administrators, managers, and scientists to help coordinate research and as an aid in selecting new programs and is divided into Sections A and B, listing all the projects, Section C, a summary of funding levels, and Section D, an index

  13. Fellowship Program in the Design and Development of Instructional Materials. Final Report.

    Science.gov (United States)

    Fleming, Malcolm; Pett, Dennis

    A two-year graduate program leading to a specialists's degree was administered to train individuals in the design of instructional materials for elementary, secondary, vocational and special education curricula. The program sought to achieve a multiplier effect by placing its graduates in positions in which they could help other educators to…

  14. Mechanics of composite materials - 1983. Proceedings of the Symposium, Boston, MA, November 13-18, 1983

    International Nuclear Information System (INIS)

    Dvorak, G.J.

    1983-01-01

    The present conference discusses plate theories applicable to laminated composites, the analysis of large deformations in layered composite shells, composite plate nonlinear bending effects, hybrid composite constitutive behavior, polymeric material life prediction by means of kinetic fracture mechanics, and crack growth direction in fibrous composites. Also discussed are stress singularities and solution structures, together with the delamination behavior and fracture mechanics parameters, of delamination mechanics in fiber-reinforced composites, followed by the theory and applications of unidirectional composite fracture, impact and fatigue behavior in graphite-epoxy laminates, and the fracture behavior of notched unidirectional boron/aluminum composite laminates

  15. Improvement of thermo-mechanical properties of ceramic materials for nuclear applications

    International Nuclear Information System (INIS)

    Decroix, G.M.; Gosset, D.; Kryger, B.; Boussuge, M.; Burlet, H.

    1994-01-01

    In order to improve the thermo-mechanical properties of materials used as neutron absorbers in nuclear reactors, cermet or cercer have been produced with two original microstructures: micro- or macro-dispersed composites. The composites thermal shock resistance has been evaluated in an image furnace. The microstructures we obtained involve different reinforcement mechanisms, such as crack deflection, crack branching, crack bridging or microcrack toughening, and improvement of thermal conductivity. The results reveal a significant improvement of the thermo-mechanical properties of the boron base neutron absorbers whose fabrication process leads to a macro-dispersed microstructure. (authors). 8 refs., 8 figs., 2 tabs

  16. German Language and Culture: 9-Year Program Classroom Assessment Materials, Grade 4

    Science.gov (United States)

    Alberta Education, 2008

    2008-01-01

    This document is designed to provide assessment materials for specific Grade 4 outcomes in the German Language and Culture Nine-year Program, Grades 4-5-6. The assessment materials are designed for the beginner level in the context of teaching for communicative competence. Grade 4 learning outcomes from the German Language and Culture Nine-year…

  17. Japanese Language and Culture: 9-Year Program Classroom Assessment Materials, Grade 4

    Science.gov (United States)

    Alberta Education, 2008

    2008-01-01

    This document is designed to provide assessment materials for specific Grade 4 outcomes in the Japanese Language and Culture Nine-year Program, Grades 4-5-6. The assessment materials are designed for the beginner level in the context of teaching for communicative competence. Grade 4 learning outcomes from the Japanese Language and Culture…

  18. FWP executive summaries, Basic Energy Sciences Materials Sciences Programs (SNL/NM)

    Energy Technology Data Exchange (ETDEWEB)

    Samara, G.A.

    1997-05-01

    The BES Materials Sciences Program has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia`s expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials synthesis and processing science to produce new classes of tailored materials as well as to enhance the properties of existing materials for US energy applications and for critical defense needs. Current core research in this program includes the physics and chemistry of ceramics synthesis and processing, the use of energetic particles for the synthesis and study of materials, tailored surfaces and interfaces for materials applications, chemical vapor deposition sciences, artificially-structured semiconductor materials science, advanced growth techniques for improved semiconductor structures, transport in unconventional solids, atomic-level science of interfacial adhesion, high-temperature superconductors, and the synthesis and processing of nano-size clusters for energy applications. In addition, the program includes the following three smaller efforts initiated in the past two years: (1) Wetting and Flow of Liquid Metals and Amorphous Ceramics at Solid Interfaces, (2) Field-Structured Anisotropic Composites, and (3) Composition-Modulated Semiconductor Structures for Photovoltaic and Optical Technologies. The latter is a joint effort with the National Renewable Energy Laboratory. Separate summaries are given of individual research areas.

  19. Industry to Education Technology Transfer Program. Composite Materials--Personnel Development. Final Report.

    Science.gov (United States)

    Tomezsko, Edward S. J.

    A composite materials education program was established to train Boeing Helicopter Company employees in the special processing of new filament-reinforced polymer composite materials. During the personnel development phase of the joint Boeing-Penn State University project, an engineering instructor from Penn State completed a 5-month, full-time…

  20. Users manual. Pursuit program of use licenses of radioactive material or generator equipment of ionizing radiations

    International Nuclear Information System (INIS)

    Becerril M, V.M.; Villarreal, J.E.

    1992-05-01

    The objective of the program 'Databases for the pursuit of licenses of use of radioactive material', it consists on the application of a computer system carried out in dbase IV that it allows the control of the all the information related with those licenses for use, possession and storage of radioactive material or generator equipment of ionizing radiations. (Author)