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Sample records for softening heat treatment

  1. TO SELECTION OF TECHNOLOGICAL SCHEME OF SOFTENING HEAT TREATMENT FOR HIGH CHROMIUM CAST IRON

    Directory of Open Access Journals (Sweden)

    V. G. Efremenko

    2014-03-01

    Full Text Available Purpose. High chromium cast irons with austenitic matrix have low machinability. The aim of work is search of new energy-saving modes of preliminary softening heat treatment enhancing the machinability of castings by forming an optimum microstructure. Methodology. Metallographic analysis, hardness testing and machinability testing are applied. Findings. It was found out that high temperature annealing with continuous cooling yields to martensite-austenite matrix in cast iron 270Х15Г2Н1MPhT, which abruptly affects the machinability of cast iron. Significant improvement of machinability is achieved by forming of structure "ferrite + granular carbides" and by decline of hardness to 37-39 HRC in the case of two-stage isothermal annealing in the subcritical temperature range or by the use of quenching and tempering (two-step or cyclic. Originality. It was found that the formation of the optimal structure of the matrix and achievement of desired hardness level needed for improving machinability of high chromium cast iron containing 3 % austenite-forming elements, can be obtained: 1 due to pearlite original austenite followed by spherodization eutectoid carbides, and 2 by getting predominantly martensite structure followed by the decay of martensite and carbides coagulation at high-temperature tempering. Practical value. The new energy-saving schemes of softening heat treatment to ensure the growth of machinability of high chromium cast iron, alloyed by higher quantity of austenite forming elements, are proposed.

  2. Improve the material absorption of light and enhance the laser tube bending process utilizing laser softening heat treatment

    Science.gov (United States)

    Imhan, Khalil Ibraheem; Baharudin, B. T. H. T.; Zakaria, Azmi; Ismail, Mohd Idris Shah B.; Alsabti, Naseer Mahdi Hadi; Ahmad, Ahmad Kamal

    2018-02-01

    Laser forming is a flexible control process that has a wide spectrum of applications; particularly, laser tube bending. It offers the perfect solution for many industrial fields, such as aerospace, engines, heat exchangers, and air conditioners. A high power pulsed Nd-YAG laser with a maximum average power of 300 W emitting at 1064 nm and fiber-coupled is used to irradiate stainless steel 304 (SS304) tubes of 12.7 mm diameter, 0.6 mm thickness and 70 mm length. Moreover, a motorized rotation stage with a computer controller is employed to hold and rotate the tube. In this paper, an experimental investigation is carried out to improve the laser tube bending process by enhancing the absorption coefficient of the material and the mechanical formability using laser softening heat treatment. The material surface is coated with an oxidization layer; hence, the material absorption of laser light is increased and the temperature rapidly rises. The processing speed is enhanced and the output bending angle is increased to 1.9° with an increment of 70% after the laser softening heat treatment.

  3. Influence of softening sequencing on electrocoagulation treatment of produced water.

    Science.gov (United States)

    Esmaeilirad, Nasim; Carlson, Ken; Omur Ozbek, Pinar

    2015-01-01

    Electrocoagulation has been used to remove solids and some metals from both water and wastewater sources for decades. Additionally, chemical softening is commonly employed in water treatment systems to remove hardness. This paper assesses the combination and sequence of softening and EC methods to treat hydraulic fracturing flowback and produced water from shale oil and gas operations. EC is one of the available technologies to treat produced water for reuse in frac fluids, eliminating not only the need to transport more water but also the costs of providing fresh water. In this paper, the influence of chemical softening on EC was studied. In the softening process, pH was raised to 9.5 and 10.2 before and after EC, respectively. Softening, when practiced before EC was more effective for removing turbidity with samples from wells older than one month (99% versus 88%). However, neither method was successful in treating samples collected from early flowback (1-day and 2-day samples), likely due to the high concentration of organic matter. For total organic carbon, hardness, Ba, Sr, and B removal, application of softening before EC appeared to be the most efficient approach, likely due to the formation of solids before the coagulation process. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Bacterial Colonization of Pellet Softening Reactors Used during Drinking Water Treatment

    NARCIS (Netherlands)

    Hammes, F.; Boon, N.; Vital, M.; Ross, P.; Magic-Knezev, A.; Dignum, M.

    2010-01-01

    Pellet softening reactors are used in centralized and decentralized drinking water treatment plants for the removal of calcium (hardness) through chemically induced precipitation of calcite. This is accomplished in fluidized pellet reactors, where a strong base is added to the influent to increase

  5. The Etiology and Treatment of the Softened Phallus after the Radial Forearm Osteocutaneous Free Flap Phalloplasty

    Directory of Open Access Journals (Sweden)

    Seok-Kwun Kim

    2012-07-01

    Full Text Available BackgroundThe radial forearm osteocutaneous free flap is considered to be the standard technique for penile construction. One year after their operation, most patients experience a softened phallus, so that they suffer from difficulties in sexual intercourse. In this report, we present our experience with phalloplasty by radial forearm osteocutaneous free flap, as well as an evaluation of the etiology and treatment of the softened phallus.MethodsBetween March 2005 and February 2010, 58 patients underwent phalloplasty by radial forearm osteocutaneous free flap. Most of their neophallus had been softened subjectively and among them, 12 patients who wanted correction were investigated. We performed repetitive fat injection, artificial dermis grafting, silicone rod insertion, and rib bone with cartilaginous tip graft. Physical examination, plain radiograph, computed tomography, bone scintigraphy, and satisfaction scores were investigated.ResultsMost of the participants' penises have been softened after phalloplasty, and the skin elasticity had been also decreased. On plain radiograph, the distal end of the bone was self-rounded; however, the bone shape of the neophallus had no significant interval changes or resorption. Computed tomography showed equivocal density of cortical bone. On bone scintigraphy, the bone metabolism was active at 3 months postoperatively, and remained active 9 years postoperatively.ConclusionsThe use of a rib bone with cartilaginous tip graft could be an option for improvement of the softened phallus. Silicon rod insertion is also worth considering for rigidity of the softened phallus. Decreased rigidity due to soft tissue atrophy could be alleviated with repeated fat injection and artificial dermis grafting.

  6. A multicentre randomised controlled trial and economic evaluation of ion-exchange water softeners for the treatment of eczema in children: the Softened Water Eczema Trial (SWET).

    Science.gov (United States)

    Thomas, K S; Koller, K; Dean, T; O'Leary, C J; Sach, T H; Frost, A; Pallett, I; Crook, A M; Meredith, S; Nunn, A J; Burrows, N; Pollock, I; Graham-Brown, R; O'Toole, E; Potter, D; Williams, H C

    2011-02-01

    To determine whether installation of an ion-exchange water softener in the home could improve atopic eczema in children and, if so, to establish its likely cost and cost-effectiveness. An observer-blind, parallel-group randomised controlled trial of 12 weeks duration followed by a 4-week observational period. Eczema was assessed by research nurses blinded to intervention at baseline, 4 weeks, 12 weeks and 16 weeks. The primary outcome was analysed as intent-to-treat, using the randomised allocation rather than actual treatment received. A secondary per-protocol analysis excluded participants who failed to receive their allocated treatment and who were deemed to be protocol violators. Secondary and primary care referral centres in England (UK) serving a variety of ethnic and social groups and including children living in both urban and periurban homes. Three hundred and thirty-six children (aged 6 months to 16 years) with moderate/severe atopic eczema, living in homes in England supplied by hard water (≥ 200 mg/l calcium carbonate). Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care (group A) for 12 weeks or usual eczema care alone (group B) for 12 weeks. This was followed by a 4-week observational period, during which water softeners were switched off/removed from group A homes and installed in group B homes. Standard procedure was to soften all water in the home, but to provide mains (hard) water at a faucet-style tap in the kitchen for drinking and cooking. Participants were therefore exposed to softened water for bathing and washing of clothes, but continued to drink mains (hard) water. Usual care was defined as any treatment that the child was currently using in order to control his or her eczema. New treatment regimens used during the trial period were documented. Primary outcome was the difference between group A and group B in mean change in disease severity at 12 weeks compared with baseline, as

  7. Plasma assisted heat treatment: annealing

    International Nuclear Information System (INIS)

    Brunatto, S F; Guimaraes, N V

    2009-01-01

    This work comprises a new dc plasma application in the metallurgical-mechanical field, called plasma assisted heat treatment, and it presents the first results for annealing. Annealing treatments were performed in 90% reduction cold-rolled niobium samples at 900 deg. C and 60 min, in two different heating ways: (a) in a hollow cathode discharge (HCD) configuration and (b) in a plasma oven configuration. The evolution of the samples' recrystallization was determined by means of the microstructure, microhardness and softening rate characterization. The results indicate that plasma species (ions and neutrals) bombardment in HCD plays an important role in the recrystallization process activation and could lead to technological and economical advantages considering the metallic materials' heat treatment application. (fast track communication)

  8. A randomised controlled trial of ion-exchange water softeners for the treatment of eczema in children.

    Directory of Open Access Journals (Sweden)

    Kim S Thomas

    2011-02-01

    Full Text Available Epidemiological studies and anecdotal reports suggest a possible link between household use of hard water and atopic eczema. We sought to test whether installation of an ion-exchange water softener in the home can improve eczema in children.This was an observer-blind randomised trial involving 336 children (aged 6 months to 16 years with moderate/severe atopic eczema. All lived in hard water areas (≥200 mg/l calcium carbonate. Participants were randomised to either installation of an ion-exchange water softener plus usual eczema care, or usual eczema care alone. The primary outcome was change in eczema severity (Six Area Six Sign Atopic Dermatitis Score, SASSAD at 12 weeks, measured by research nurses who were blinded to treatment allocation. Analysis was based on the intent-to-treat population. Eczema severity improved for both groups during the trial. The mean change in SASSAD at 12 weeks was -5.0 (20% improvement for the water softener group and -5.7 (22% improvement for the usual care group (mean difference 0.66, 95% confidence interval -1.37 to 2.69, p = 0.53. No between-group differences were noted in the use of topical corticosteroids or calcineurin inhibitors.Water softeners provided no additional benefit to usual care in this study population. Small but statistically significant differences were found in some secondary outcomes as reported by parents, but it is likely that such improvements were the result of response bias, since participants were aware of their treatment allocation. A detailed report for this trial is also available at http://www.hta.ac.uk.Current Controlled Trials ISRCTN71423189 Please see later in the article for the Editors' Summary.

  9. Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening

    OpenAIRE

    Wombacher, William D.; Hornbuckle, Keri C.

    2009-01-01

    Synthetic musk fragrances are common personal care product additives and wastewater contaminants that are routinely detected in the environment. This study examines the presence eight synthetic musk fragrances (AHTN, HHCB, ATII, ADBI, AHMI, musk xylene, and musk ketone) in source water and the removal of these compounds as they flow through a Midwestern conventional drinking water plant with lime softening. The compounds were measured in water, waste sludge, and air throughout the plant. HHCB...

  10. A multicentre randomised controlled trial and economic evaluation of ion-exchange water softeners for the treatment of eczema in children:the Softened Water Eczema Trial (SWET)

    OpenAIRE

    Thomas, K. S.; Koller, K.; Dean, Tara; O'Leary, C. J.; Sach, T. H.; Frost, A.; Pallett, I.; Crook, A. M.; Meredith, S.; Nunn, A. J.; Burrows, N.; Pollock, I.; Graham-Brown, R.; O'Toole, E.; Potter, D.

    2011-01-01

    Objectives: To determine whether installation of an ion-exchange water softener in the home could improve atopic eczema in children and, if so, to establish its likely cost and cost-effectiveness. Design: An observer-blind, parallel-group randomised controlled trial of 12 weeks duration followed by a 4-week observational period. Eczema was assessed by research nurses blinded to intervention at baseline, 4 weeks, 12 weeks and 16 weeks. The primary outcome was analysed as intent-to-treat, using...

  11. Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening.

    Science.gov (United States)

    Wombacher, William D; Hornbuckle, Keri C

    2009-11-01

    Synthetic musk fragrances are common personal care product additives and wastewater contaminants that are routinely detected in the environment. This study examines the presence eight synthetic musk fragrances (AHTN, HHCB, ATII, ADBI, AHMI, musk xylene, and musk ketone) in source water and the removal of these compounds as they flow through a Midwestern conventional drinking water plant with lime softening. The compounds were measured in water, waste sludge, and air throughout the plant. HHCB and AHTN were detected in 100% of the samples and at the highest concentrations. A mass balance on HHCB and AHTN was performed under warm and cold weather conditions. The total removal efficiency for HHCB and AHTN, which averaged between 67% to 89%, is dominated by adsorption to water softener sludge and its consequent removal by sludge wasting and media filtration. Volatilization, chlorine disinfection, and the disposal of backwash water play a minor role in the removal of both compounds. As a result of inefficient overall removal, HHCB and AHTN are a constant presence at low levels in finished drinking water.

  12. Effect of water treatment additives on lime softening residual trace chemical composition--implications for disposal and reuse.

    Science.gov (United States)

    Cheng, Weizhi; Roessler, Justin; Blaisi, Nawaf I; Townsend, Timothy G

    2014-12-01

    Drinking water treatment residues (WTR) offer potential benefits when recycled through land application. The current guidance in Florida, US allows for unrestricted land application of lime softening WTR; alum and ferric WTR require additional evaluation of total and leachable concentrations of select trace metals prior to land application. In some cases a mixed WTR is produced when lime softening is accompanied by the addition of a coagulant or other treatment chemical; applicability of the current guidance is unclear. The objective of this research was to characterize the total and leachable chemical content of WTR from Florida facilities that utilize multiple treatment chemicals. Lime and mixed lime WTR samples were collected from 18 water treatment facilities in Florida. Total and leachable concentrations of the WTR were measured. To assess the potential for disposal of mixed WTR as clean fill below the water table, leaching tests were conducted at multiple liquid to solid ratios and under reducing conditions. The results were compared to risk-based soil and groundwater contamination thresholds. Total metal concentrations of WTR were found to be below Florida soil contaminant thresholds with Fe found in the highest abundance at a concentration of 3600 mg/kg-dry. Aluminum was the only element that exceeded the Florida groundwater contaminant thresholds using SPLP (95% UCL = 0.23 mg/L; risk threshold = 0.2 mg/L). Tests under reducing conditions showed elevated concentrations of Fe and Mn, ranging from 1 to 3 orders of magnitude higher than SPLP leachates. Mixed lime WTR concentrations (total and leachable) were lower than the ferric and alum WTR concentrations, supporting that mixed WTR are appropriately represented as lime WTR. Testing of WTR under reducing conditions demonstrated the potential for release of certain trace metals (Fe, Al, Mn) above applicable regulatory thresholds; additional evaluation is needed to assess management options where

  13. Heat treatment furnace

    Science.gov (United States)

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  14. Circular economy in drinking water treatment: reuse of ground pellets as seeding material in the pellet softening process.

    Science.gov (United States)

    Schetters, M J A; van der Hoek, J P; Kramer, O J I; Kors, L J; Palmen, L J; Hofs, B; Koppers, H

    2015-01-01

    Calcium carbonate pellets are produced as a by-product in the pellet softening process. In the Netherlands, these pellets are applied as a raw material in several industrial and agricultural processes. The sand grain inside the pellet hinders the application in some high-potential market segments such as paper and glass. Substitution of the sand grain with a calcite grain (100% calcium carbonate) is in principle possible, and could significantly improve the pellet quality. In this study, the grinding and sieving of pellets, and the subsequent reuse as seeding material in pellet softening were tested with two pilot reactors in parallel. In one reactor, garnet sand was used as seeding material, in the other ground calcite. Garnet sand and ground calcite performed equally well. An economic comparison and a life-cycle assessment were made as well. The results show that the reuse of ground calcite as seeding material in pellet softening is technologically possible, reduces the operational costs by €38,000 (1%) and reduces the environmental impact by 5%. Therefore, at the drinking water facility, Weesperkarspel of Waternet, the transition from garnet sand to ground calcite will be made at full scale, based on this pilot plant research.

  15. Cation Exchange Water Softeners

    Science.gov (United States)

    WaterSense released a notice of intent to develop a specification for cation exchange water softeners. The program has made the decision not to move forward with a spec at this time, but is making this information available.

  16. The effect of gas tungsten arc welding and pulsed-gas tungsten arc welding processes’ parameters on the heat affected zone-softening behavior of strain-hardened Al–6.7Mg alloy

    International Nuclear Information System (INIS)

    Hadadzadeh, Amir; Ghaznavi, Majid Mahmoudi; Kokabi, Amir Hossein

    2014-01-01

    Highlights: • The strain-hardened Al–6.7Mg alloy was welded using GTAW and PGTAW processes. • The HAZ softening behavior of the welding joint was characterized. • Employing pulsed current in GTAW process eliminated the HAZ softening. • Duration ratio did not affect the weld strength while the frequency influenced it. - Abstract: The heat affected zone (HAZ) softening behavior of strain-hardened Al–6.7Mg alloy welded by gas tungsten arc welding (GTAW) process was investigated. Increasing the heat input during welding led to formation of a wider HAZ. Moreover, the size of the precipitates was increased at higher heat inputs. Consequently, by increasing the heat input, lower strength was obtained for the welding joints. At the second stage of the study, pulsed-GTAW (PGTAW) process was employed to improve the strength of the joints. It was observed that the overall strength of the welding joints was improved and the fracture during tensile test was moved from the HAZ to the fusion zone. Moreover, the effect of duration ratio and pulse frequency was studied. For the current study, the duration ratio did not have a significant effect on the strength and microstructure of the weld, but increasing the frequency led to higher strength of the weld and finer microstructure

  17. REMOVAL OF BERYLLIUM FROM DRINKING WATER BY CHEMICAL COAGULATION AND LIME SOFTENING

    Science.gov (United States)

    The effectiveness of conventional drinking water treatment and lime softening was evaluated for beryllium removal from two drinking water sources. ar test studies were conducted to determine how common coagulants (aluminum sulfate and ferric chloride and lime softening performed ...

  18. 29 CFR 1919.80 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.80 Section 1919.80 Labor Regulations...) GEAR CERTIFICATION Certification of Shore-Based Material Handling Devices § 1919.80 Heat treatment. (a) Wherever heat treatment of any loose gear is recommended by the manufacturer, it shall be carried out in...

  19. 29 CFR 1919.36 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.36 Section 1919.36 Labor Regulations...) GEAR CERTIFICATION Certification of Vessels: Tests and Proof Loads; Heat Treatment; Competent Persons § 1919.36 Heat treatment. (a) The annealing of wrought iron gear required by this part shall be...

  20. Surface engineering and heat treatment

    International Nuclear Information System (INIS)

    Morton, P.H.

    1991-01-01

    This book is the proceedings of a Conference organised jointly by The Institute of Metals and The Centre for Exploitation of Science and Technology (CEST). It sets out to review this role and point the way to the future by collecting together a series of invited papers written by noted authorities in their fields. The opening review by CEST highlights the economic and industrial importance of Surface Engineering and is followed by a group of four articles devoted to specific branches of industry. Several technical papers then describe various aspects of the development of heat treatment over the last twenty-five years. These are followed by papers describing advances made possible by new technologies such as plasma, laser and ion beam. A separate abstract has been prepared for a paper on materials aspects of ion beam technology. (author)

  1. Hemodialysis Catheter Heat Transfer for Biofilm Prevention and Treatment.

    Science.gov (United States)

    Richardson, Ian P; Sturtevant, Rachael; Heung, Michael; Solomon, Michael J; Younger, John G; VanEpps, J Scott

    2016-01-01

    Central line-associated bloodstream infections (CLABSIs) are not easily treated, and many catheters (e.g., hemodialysis catheters) are not easily replaced. Biofilms (the source of infection) on catheter surfaces are notoriously difficult to eradicate. We have recently demonstrated that modest elevations of temperature lead to increased staphylococcal susceptibility to vancomycin and significantly soften the biofilm matrix. In this study, using a combination of microbiological, computational, and experimental studies, we demonstrate the efficacy, feasibility, and safety of using heat as an adjuvant treatment for infected hemodialysis catheters. Specifically, we show that treating with heat in the presence of antibiotics led to additive killing of Staphylococcus epidermidis with similar trends seen for Staphylococcus aureus and Klebsiella pneumoniae. The magnitude of temperature elevation required is relatively modest (45-50°C) and similar to that used as an adjuvant to traditional cancer therapy. Using a custom-designed benchtop model of a hemodialysis catheter, positioned with tip in the human vena cava as well as computational fluid dynamic simulations, we demonstrate that these temperature elevations are likely achievable in situ with minimal increased in overall blood temperature.

  2. Heat treatment of nickel alloys

    International Nuclear Information System (INIS)

    Smith, D.F. Jr.; Clatworthy, E.F.

    1975-01-01

    A heat treating process is described that can be used to produce desired combinations of strength, ductility, and fabricability characteristics in heat resistant age-hardenable alloys having precipitation-hardening amounts of niobium, titanium, and/or tantalum in a nickel-containing matrix. (U.S.)

  3. 29 CFR 1919.16 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.16 Section 1919.16 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels' Cargo Gear § 1919.16 Heat treatment. (a) All chains (other...

  4. Advances in the heat treatment of steels

    International Nuclear Information System (INIS)

    Morris, J.W. Jr.; Kim, J.I.; Syn, C.K.

    1978-06-01

    A number of important recent advances in the processing of steels have resulted from the sophisticated uses of heat treatment to tailor the microstructure of the steels so that desirable properties are established. These new heat treatments often involve the tempering or annealing of the steel to accompish a partial or complete reversion from martensite to austenite. The influence of these reversion heat treatments on the product microstructure and its properties may be systematically discussed in terms of the heat treating temperature in relation to the phase diagram. From this perspective, four characteristic heat treatments are defined: (1) normal tempering, (2) inter-critical tempering, (3) intercritical annealing, and (4) austenite reversion. The reactions occurring during each of these treatments are described and the nature and properties of typical product microstructures discussed, with specific reference to new commercial or laboratory steels having useful and exceptional properties

  5. MATHEMATICAL MODELING OF HEATING RATE PRODUCT AT HIGH HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    M. M. Akhmedova

    2014-01-01

    Full Text Available Methods of computing and mathematical modeling are all widely used in the study of various heat exchange processes that provide the ability to study the dynamics of the processes, as well as to conduct a reasonable search for the optimal technological parameters of heat treatment.This work is devoted to the identification of correlations among the factors that have the greatest effect on the rate of heating of the product at hightemperature heat sterilization in a stream of hot air, which are chosen as the temperature difference (between the most and least warming up points and speed cans during heat sterilization.As a result of the experimental data warming of the central and peripheral layers compote of apples in a 3 liter pot at high-temperature heat treatment in a stream of hot air obtained by the regression equation in the form of a seconddegree polynomial, taking into account the effects of pair interaction of these parameters. 

  6. Heat Treatment of Tools in Light Industry

    Science.gov (United States)

    Petukhov, V. A.

    2005-09-01

    Heat treatment processes for some tools (knitting needles, travelers for thimbles of spinning and doubling frames, thread-forming spinnerets) used for the production of cloths, hosiery, and other articles) in the knitting and textile industries are considered. Problems of the choice of steel and the kind and parameters of heat treatment are discussed in connection with the special features of tool design and operating conditions.

  7. Heat-treatment and heat-to-heat variations in the fracture toughness of Alloy 718

    International Nuclear Information System (INIS)

    Mills, W.J.

    1981-07-01

    The effect of heat-treatment and heat-to-heat variations on the J Ic fracture toughness response of Alloy 718 was examined at room and elevated temperatures using the multiple-specimen R-curve technique. Six heats of alloy 718 were tested in the conventional and modified heat-treated conditions. The fracture toughness response for the modified superalloy was found to be superior to that exhibited by the conventional material. Heat-to-heat variations in the J Ic response of Alloy 718 were observed in both heat-treated conditions; the modified treatment exhibited much larger variability. The J Ic and corresponding K Ic fracture toughness values were analyzed statistically to establish minimum expected toughness, values for use in design and safety analyses. 26 refs., 10 figs., 9 tabs

  8. 49 CFR 179.400-12 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.400-12 Section 179... and 107A) § 179.400-12 Postweld heat treatment. (a) Postweld heat treatment of the inner tank is not... be attached before postweld heat treatment. Welds securing the following need not be postweld heat...

  9. Failures of tool steels after heat treatments

    International Nuclear Information System (INIS)

    Nunez-Gonzalez, G.

    1990-01-01

    The main objective of the work was to determine the most common defects occuring in tool steels of the AISI D-2, S-1, 0-1 and W-2 series during thermal treatment. Defects were evaluated by metallographic analyses, a method used to determine and recognize micro structural defects and their origin in order to be able to eliminate and correct some of the stages that are caused by heat treatment. Results show a large number of defects due to irregularities during thermal heating such as excess or lack of temperature, heating time, and atmosphere, rectifying and handling in service and, to a lesser extent, poor design. In conclusion, with the results obtained for each of the thermal treatments it is necessary to define, particularly the values each of these variables should have since they affect the material properties. (Author)

  10. Lowcost automated control for steel heat treatments

    International Nuclear Information System (INIS)

    Zambaldi, Edimilson; Magalhães, Ricardo R.; Barbosa, Bruno H.G.; Silva, Sandro P. da; Ferreira, Danton D.

    2017-01-01

    Highlights: • Control the furnace temperature measured by thermocouple and adjusts it. • Activating the furnace resistors through Pulse Width Modulation. • Appling heat treatments to steels by a low-cost controller. - Abstract: The aim of this paper is to propose a low cost, automated furnace control system for the heat treatment of steel. We used an open source electronic prototyping platform to control the furnace temperature, thus reducing human interaction during the heat process. The platform can be adapted to non-controlled commercial furnaces, which are often used by small businesses. A Proportional-Integral-Derivative (PID) controller was implemented to regulate the furnace temperature based on a defined heat treatment cycle. The embedded system activates the furnace resistors through Pulse Width Modulation (PWM), allowing for control of electrical power supplied to the furnace. Hardening and tempering were performed on standard steel samples using a traditional method (visual inspection without temperature control) as well the embedded system with PID feedback control. The results show that the proposed system can reproduce an arbitrary heat treatment curve with accuracy and provide the desired final hardness as inferred through metallographic analysis. In addition, we observed a 6% saving in energy consumption using the proposed control system. Furthermore, the estimated cost to implement the system is 42% lower than a commercial controller model implemented in commercial furnaces.

  11. Basic process of irradiation softening

    International Nuclear Information System (INIS)

    Makii, Koichi; Tsutsumi, Tetsuo; Aono, Yasuhisa; Kuramoto, Eiichi

    1987-01-01

    The authors have been engaged in research that uses the Johnson-Wilson potential (i.e., potential between two bodies) to analyze the interaction between the core of a spiral dislocation and point defects (interstitial atoms) under stress. Metals with the body-centered cubic structure, however, have covalent bonding nature and multi-body effects of d-electrons cannot be ignored. In the present work, the N-body potential, which takes into account such multi-body effects of d-electrons, is compared with the Johnson-Wilson potential. Compared to the Johnson-Wilson potential, the N-body potential suffers a considerably smaller misfit energy and allows computer simulation of the interaction to be performed at an external force level closer to that used in measurement. Low-stress, long-period relaxation causes pipe diffusion of crowdions. This causes the expansion of ''three-kink configuration'', leading to hardening. As a result of the pipe diffusion, crowdions are absorbed into spiral dislocations and released out of the crystal. It has been reported that during a tensile test at 77 K, irradiated samples are softened at the yield point and the degree of softening recovers as the strain increases. This also supports the idea that the number of defects decreases due to the interaction between dislocations and interstitial atoms. (Nogami, K.)

  12. 49 CFR 179.220-11 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.220-11 Section 179... Postweld heat treatment. (a) Postweld heat treatment of the inner container is not a specification requirement. (b) Postweld heat treatment of the cylindrical portions of the outer shell to which the anchorage...

  13. 49 CFR 179.500-6 - Heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Heat treatment. 179.500-6 Section 179.500-6...-6 Heat treatment. (a) Each necked-down tank shall be uniformly heat treated. Heat treatment shall... treatment of alternate steels shall be approved. All scale shall be removed from outside of tank to an...

  14. Life cycle assessment of central softening of very hard drinking water

    DEFF Research Database (Denmark)

    Godskesen, Berit; Hauschild, Michael Zwicky; Rygaard, Martin

    2012-01-01

    Life Cycle Assessment (LCA) to quantify the environmental impacts of central softening of drinking water considering both the negative effects at the waterworks and the positive effects imposed by the changed water quality in the households. The LCA modeling considered central softening of drinking......Many consumers prefer softened water due to convenience issues such as avoidance of removing limescale deposits from household appliances and surfaces, and to reduce consumption of cleaning agents and laundry detergents leading to lower household expenses. Even though central softening of drinking...... water entailed an increased use of energy, sand and chemicals at the waterworks, the distributed and softened drinking water supported a decrease in consumption of energy and chemical agents in the households along with a prolonged service life of household appliances which heat water. This study used...

  15. Assembly for melting and heat treatment

    International Nuclear Information System (INIS)

    Blumenfeld, M.

    1976-11-01

    Laboratory scale production of alloys having a precise alloying materials content and the exact heat treatment of metallurgical specimens are discussed. The design and assembly of two relevant instruments are described. These instruments include a laboratory vacuum induction furnace and a specially designed glass lathe, that enables even an unskilled operator to encapsulate and seal metallurgical specimens in glass capsules. (author)

  16. Effect of heat treatment temperature on microstructure

    Indian Academy of Sciences (India)

    The results of electrochemical performance measurements for the HCSs as anode material for lithium ion batteries indicate that the discharge capacity of the HCSs is improved after heat treatment at 800°C compared with the as-prepared HCSs and have a maximum value of 357 mAh/g and still retains 303 mAh/g after 40 ...

  17. Plasma treatment of heat-resistant materials

    International Nuclear Information System (INIS)

    Vlasov, V A; Kosmachev, P V; Skripnikova, N K; Bezukhov, K A

    2015-01-01

    Refractory lining of thermal generating units is exposed to chemical, thermal, and mechanical attacks. The degree of fracture of heat-resistant materials depends on the chemical medium composition, the process temperature and the material porosity. As is known, a shortterm exposure of the surface to low-temperature plasma (LTP) makes possible to create specific coatings that can improve the properties of workpieces. The aim of this work is to produce the protective coating on heat-resistant chamotte products using the LTP technique. Experiments have shown that plasma treatment of chamotte products modifies the surface, and a glass-ceramic coating enriched in mullite is formed providing the improvement of heat resistance. For increasing heat resistance of chamotte refractories, pastes comprising mixtures of Bacor, alumina oxide, and chamot were applied to their surfaces in different ratios. It is proved that the appropriate coating cannot be created if only one of heat-resistant components is used. The required coatings that can be used and recommended for practical applications are obtained only with the introduction of powder chamot. The paste composition of 50% chamot, 25% Bacor, and 25% alumina oxide exposed to plasma treatment, has demonstrated the most uniform surface fusion. (paper)

  18. In situ heat treatment process utilizing a closed loop heating system

    Science.gov (United States)

    Vinegar, Harold J.; Nguyen, Scott Vinh

    2010-12-07

    Systems and methods for an in situ heat treatment process that utilizes a circulation system to heat one or more treatment areas are described herein. The circulation system may use a heated liquid heat transfer fluid that passes through piping in the formation to transfer heat to the formation. In some embodiments, the piping may be positioned in at least two of the wellbores.

  19. Heat Treatment and Properties of Iron and Steel

    National Research Council Canada - National Science Library

    Digges, Thomas

    1966-01-01

    .... Chemical compositions, heat treatments, and some properties and uses are presented for structural steels, tool steels, stainless and heat-resisting steels, precipitation-hardenable stainless steels...

  20. Fabrication techniques to eliminate postweld heat treatment

    International Nuclear Information System (INIS)

    Lochhead, J.C.

    1978-01-01

    Postweld heat treatments to reduce residual stresses (stress relief operations) have been a common practice in the pressure vessel industry for a large number of years. A suitable heat treatment operation can, in particular for low alloy steels, have additional beneficial effects, i.e. a reduction in peak hardness values in the heat-affected zone, an improvement in weld metal properties, and a lowering of the adverse effects of the welding process on the mechanical properties of the parent material adjacent to the weld metal. However, continuing studies in the field of brittle fracture, improved parent materials, and more sophisticated nondestructive testing techniques have led to the elimination of such a practice in ever-increasing thickness ranges and types of material. For instance, the recently issued BS 5500 compared with BS 1113 (1969) lifts the thickness limit requiring stress relief in certain circumstances from 19 to 35mm for C steels. With respect to materials the CEGB has stated that as a result of successful operational experience it will no longer be necessary to postweld heat treat butt welds in 2 1/4 Cr-1Mo tubes of certain dimensions. Despite this trend, over a period of years a number of instances have arisen where, because of some factor, postweld heat treatment, although perhaps desirable, is not possible. This Paper describes several such examples. It must be noted that the examples quoted consist of relatively important and major items. It has been necessary within the confines of this Paper to condense the reports. It is hoped that no significant factors have been omitted. (author)

  1. Combined heat and gamma-irradiation treatments for the control of strawberry diseases under market conditions

    International Nuclear Information System (INIS)

    Brodrick, H.T.; Thomas, A.C.; Van Tonder, A.J.; Terblanche, J.C.

    1977-02-01

    The spoilage of strawberries under local market conditions was investigated. It was confirmed that the major losses are due to 'leak' disease caused by Rhizopus stolonifer (Ehr. ex Fr.) Lind. It was also established that further fruit losses in summer are due to anthracnose caused by the fungus Colletotrichum acutatum Simmonds. This is the first time that the latter pathogen has been isolated and identified and recognised as a problem on strawberries in South Africa. Studies with R. stolonifer in culture showed that 46 degrees Celsius for 20 min (the previous international standard heat treatment for fruit) was disappointing, while a treatment at 50 degrees Celsius for 10 min effectively inhibited spore germination. Irradiation studies with cultures of R. stolonifer and C. acutatum showed that a dose of 200 and 100 krad, respectively, resulted in excellent inhibition of spore germination. However, irradiating in nitrogen gas resulted in a tenfold reduction in the effectiveness of the irradiation treatments. The use of nitrogen during irradiation, therefore, cannot be considered, especially where an effective control of the fungal pathogens is desired. Investigations with different cultivars clearly demonstrated the synergistic effect on disease control obtained when combining heat and irradiation treatments. The combination treatment (moist heat at 50-52 degrees Celsius for 10 min plus 200 krad), besides effectively controlling both diseases in strawberries, did not adversely affect berry quality. In simulated transport tests it was shown that a minimal amount of berry softening did occur with this treatment, but this adverse effect was negligible compared with the beneficial effect obtained from disease control. In semi-commercial experiments it was shown that the combination heat and irradiation treatment effectively controlled spoilage diseases for a period of several days from picking, thus allowing sufficient time to market the fruit under local market

  2. Arsenic removal by lime softening

    DEFF Research Database (Denmark)

    Kaosol, T.; Suksaroj, C.; Bregnhøj, Henrik

    2002-01-01

    This paper focuses on the study of arsenic removal for drinking water by lime softening. The initial arsenic (V) concentration was 500 and 1,000 ug/L in synthetic groundwater. The experiments were performed as batch tests with varying lime dosages and mixing time. For the synthetic groundwater......, arsenic (V) removal increased with increasing lime dosage and mixing time, as well as with the resulting pH. The residual arsenic (V) in all cases was lower than the WHO guideline of 10 ug/L at pH higher than 11.5. Kinetic of arsenic (V) removal can be described by a first-order equation as C1 = C0*e......^-k*t. The relation between the constant (k value) and increasing lime dosage was found to be linear, described by k = 0.0034 (Dlime). The results support a theory from the literature that the arsenic (V) was removed by precipitation af Ca3(AsO4)2. The results obtained in the present study suggest that lime...

  3. Induction heat treatment of laser welds

    DEFF Research Database (Denmark)

    Bagger, Claus; Olsen, Flemming Ove; Sørensen, Joakim Ilsing

    2003-01-01

    of an induction coil. A number of systematic laboratory tests were then performed in order to study the effects of the coil on bead-on-plate laser welded samples. In these tests, important parameters such as coil current and distance between coil and sample were varied. Temperature measurements were made...... the laser beam as close as possible. After welding, the samples were quality assessed according to ISO 13.919-1 and tested for hardness. The metallurgical phases are analysed and briefly described. A comparison between purely laser welded samples and induction heat-treated laser welded samples is made......In this paper, a new approach based on induction heat-treatment of flat laser welded sheets is presented. With this new concept, the ductility of high strength steels GA260 with a thickness of 1.8 mm and CMn with a thickness of 2.13 mm is believed to be improved by prolonging the cooling time from...

  4. 49 CFR 179.200-11 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.200-11 Section 179.200-11 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Postweld heat treatment. When specified in § 179.201-1, after welding is complete, postweld heat treatment...

  5. The effect of treatment parameters and detergent additions on the softening of radioactively contaminated process wastewater at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Roe, M.M.; Kent, T.E.

    1993-01-01

    Oak Ridge National Laboratory (ORNL) is a research facility owned by the Department of Energy and operated by Martin Marietta Energy Systems. At ORNL, research is performed in a wide range of areas including nuclear energy research, environmental sciences, materials research, health and safety research, and production of radioisotopes. These activities generate 70 million gallons per year of process wastewater which is basically tap water and ground water containing trace amounts of radioactive compounds. This water is treated for removal of contaminants at the Process Waste Treatment Plant (PWTP) before discharge to the environment

  6. Irradiation softening in pure iron single crystals

    International Nuclear Information System (INIS)

    Meshii, M.

    1975-01-01

    The characteristics of irradiation softening in Fe were studied. Results show that irradiation softening effect can be explained by the intrinsic mechanism, namely, the interaction of screw dislocations with randomly dispersed interstitials. At least some of the solid solution softening phenomena observed in alloys can be explained by the same mechanism. However, the alloying may be accompanied by an additional effect such as solute segregation to dislocations which may also strongly affect the yield stress. This effect may mask the softening effect partially or totally. Changes in the dislocation structure of deformed specimens caused by alloying, which are often reported in electron microscopic investigations, support this contention. The alloying, therefore, may not be as good as the low temperature irradiation in studying the effect of random solutes on dislocation motion and yield stress

  7. Softening behaviour of concrete : numerical research

    NARCIS (Netherlands)

    Bongers, J.P.W.; Rutten, H.S.; Fijneman, H.J.

    1994-01-01

    Experimental research shows, apart from the influence of multiaxial loading conditions, that softening of concrete loaded in compression is accompanied by localization of deformations. Therefore, numerical modelling of concrete material behaviour has to take this effect into account. This implies

  8. Viscose liquid heat treatment using plate scraper heat exchanger

    Directory of Open Access Journals (Sweden)

    K. A. Rashkin

    2012-01-01

    Full Text Available The current work analyzes the use of different types of heat exchangers, depending on the technology of production. It is taken the detail analysis of the ways of applicability of various types of heat exchangers, depending on the viscosity of the processed product. It is posed the problem of the analytical determination of the required area of heat exchange with the use of differential equations of heat transfer in a moving liquid media, written in cylindrical coordinates, for symmetrical temperature distribution, without taking in account the energy dissipation.

  9. Life cycle assessment of central softening of very hard drinking water.

    Science.gov (United States)

    Godskesen, B; Hauschild, M; Rygaard, M; Zambrano, K; Albrechtsen, H-J

    2012-08-30

    Many consumers prefer softened water due to convenience issues such as avoidance of removing limescale deposits from household appliances and surfaces, and to reduce consumption of cleaning agents and laundry detergents leading to lower household expenses. Even though central softening of drinking water entailed an increased use of energy, sand and chemicals at the waterworks, the distributed and softened drinking water supported a decrease in consumption of energy and chemical agents in the households along with a prolonged service life of household appliances which heat water. This study used Life Cycle Assessment (LCA) to quantify the environmental impacts of central softening of drinking water considering both the negative effects at the waterworks and the positive effects imposed by the changed water quality in the households. The LCA modeling considered central softening of drinking water from the initial hardness of the region of study (Copenhagen, Denmark) which is 362 mg/L as CaCO(3) to a final hardness as CaCO(3) of 254 (a softening depth of 108) mg/L or 145 (a softening depth of 217) mg/L. Our study showed that the consumer preference can be met together with reducing the impact on the environment and the resource consumption. Environmental impacts decreased by up to 3 mPET (milli Personal Equivalent Targeted) and the break-even point from where central softening becomes environmentally beneficial was reached at a softening depth of only 22 mg/L as CaCO(3). Both energy-related and chemically related environmental impacts were reduced as well as the consumption of resources. Based on scarcity criteria, nickel was identified as the most problematic non-renewable resource in the system, and savings of up to 8 mPR (milli Person Reserve) were found. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Mortality of insect life stages during simulated heat treatment

    Science.gov (United States)

    . Heat treatment for insect disinfestation uses elevated air temperatures that are lethal to stored-product insects. Heat treatment has been demonstrated in our research to offer a reduced-risk alternative to fumigation or residual pesticide use in empty bins. Heat is also compatible with organic gr...

  11. Efficacy of heat treatment for disinfestation of concrete grain silos

    Science.gov (United States)

    Field experiments were conducted in 2007 and 2008 to evaluate heat treatment for disinfestations of empty concrete elevator silos. A Mobile Heat Treatment Unit was used to introduce heat into silos to attain target conditions of 50°C for at least 6 h. Ventilated plastic containers with a capacity of...

  12. Modification of Textile Materials' Surface Properties Using Chemical Softener

    Directory of Open Access Journals (Sweden)

    Jurgita KOŽENIAUSKIENĖ

    2011-03-01

    Full Text Available In the present study the effect of technological treatment involving the processes of washing or washing and softening with chemical cationic softener "Surcase" produced in Great Britain on the surface properties of cellulosic textile materials manufactured from cotton, bamboo and viscose spun yarns was investigated. The changes in textile materials surface properties were evaluated using KTU-Griff-Tester device and FEI Quanta 200 FEG scanning electron microscope (SEM. It was observed that the worst hand properties and the higher surface roughness are observed of cotton materials if compared with those of bamboo and viscose materials. Also, it was shown that depending on the material structure the handle parameters of knitted materials are the better than the ones of woven fabrics.http://dx.doi.org/10.5755/j01.ms.17.1.249

  13. 49 CFR 179.100-10 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.100-10 Section 179...-10 Postweld heat treatment. (a) After welding is complete, steel tanks and all attachments welded... treatment is prohibited. (c) Tank and welded attachments, fabricated from ASTM A 240/A 240M (IBR, see § 171...

  14. Stress-Softening Formulae of Polymer Bearings

    Directory of Open Access Journals (Sweden)

    M. H. B. M. Shariff

    2015-01-01

    Full Text Available The motivation for this work was the absence of closed form solutions that can reasonably describe the axial deformation behaviour of stress-softening polymer bearings. In this paper, new closed form solutions that exhibit Mullins phenomenon are developed. We show that the apparent Young modulus depends on the shape factor and the minimal infinitesimal strain. We furthermore found that, in a nonlinear deformation, the shape factor plays an important role in stress softening. The solutions are design friendly and are consistent with expected results.

  15. Communication: Surface-facilitated softening of ordinary and vapor-deposited glasses

    Science.gov (United States)

    Cubeta, Ulyana; Bhattacharya, Deepanjan; Sadtchenko, Vlad

    2017-08-01

    A common distinction between the ordinary glasses formed by melt cooling and the stable amorphous films formed by vapor deposition is the apparent mechanism of their devitrification. Using quasi-adiabatic, fast scanning calorimetry that is capable of heating rates in excess of 105 K s-1, we have investigated the softening kinetics of micrometer-scale, ordinary glass films of methylbenzene and 2-propanol. At the limit of high heating rates, the transformation mechanism of ordinary glasses is identical to that of their stable vapor-deposited counterparts. In both cases, softening is likely to begin at the sample surface and progress into its bulk via a transformation front. Furthermore, such a surface-facilitated mechanism complies with zero-order, Arrhenius rate law. The activation energy barriers for the softening transformation imply that the kinetics must be defined, at least in part, by the initial thermodynamic and structural state of the samples.

  16. Not changing minds but softening hearts.

    Science.gov (United States)

    Morey, Jerad

    2013-01-01

    When a political decision threatened to divide communities, the Minnesota Council of Churches found a way not to change minds but to soften hearts. The Respectful Conversations Project built empathy and improved relationships, and is still helping to bring peace to communities and strengthening civic engagement in the state.

  17. Softening and elution of monomers in ethanol

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Asmussen, Erik; Munksgaard, E Christian

    2009-01-01

    The purpose of this study was to investigate the effect of light-curing protocol on softening and elution of monomers in ethanol as measured on a model polymer. It was a further aim to correlate the measured values with previously reported data on degree of conversion and glass transition...

  18. Softening behaviour of concrete : experimental research

    NARCIS (Netherlands)

    Geel, van H.J.G.M.; Rutten, H.S.; Fijneman, H.J.

    1994-01-01

    Uniaxial compressive softening tests on two types of concrete have been carried out, varying the type of loading platen and specimen size. In total 37 specimens were tested, 18 with polished steel loading platens and 19 with teflon loading platens. Half of the specimens were made of normal strength

  19. Effects of heat treatment on the radiosensitivity of Salmonellae

    International Nuclear Information System (INIS)

    Choi, E.H.; Yang, J.S.; Lee, S.R.

    1978-01-01

    When the food poisoning bacteria Salmonella enteritidis and S. typhimurium were treated with radiation (cobalt-60 γ-rays) and heat (10 minutes at 45 0 C or 50 0 C), their sterilizing effect was revealed differently depending on the order of treatments. Post-irradiation heating showed a synergistic effect whereas pre-irradiation heating revealed the opposite effect and the effects differed slightly with heating temperature. (author)

  20. 49 CFR 179.300-10 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.300-10 Section 179.300-10 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Postweld heat treatment. After welding is complete, steel tanks and all attachments welded thereto, must be...

  1. Effect of heat treatment on structure and magnetic properties

    Indian Academy of Sciences (India)

    Fe46Co35Ni19/CNTs nanocomposites have been prepared by an easy two-step route including adsorption and heat treatment processes. We investigated the effect of heat treatment conditions on structure, morphology, nanoparticle sizes and magnetic properties of the Fe46Co35Ni19 alloy nanoparticles attached on the ...

  2. 7 CFR 58.236 - Pasteurization and heat treatment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pasteurization and heat treatment. 58.236 Section 58... Service 1 Operations and Operating Procedures § 58.236 Pasteurization and heat treatment. All milk and... is handled according to sanitary conditions approved by the Administrator. (a) Pasteurization. (1...

  3. Effect of heat treatment temperature on binder thermal conductivities

    International Nuclear Information System (INIS)

    Wagner, P.

    1975-12-01

    The effect of heat treatment on the thermal conductivities of a pitch and a polyfurfuryl alcohol binder residue was investigated. Graphites specially prepared with these two binders were used for the experiments. Measured thermal conductivities were treated in terms of a two-component system, and the binder thermal conductivities were calculated. Both binder residues showed increased thermal conductivity with increased heat treatment temperature

  4. Investigation of anodic oxide coatings on zirconium after heat treatment

    International Nuclear Information System (INIS)

    Sowa, Maciej; Dercz, Grzegorz; Suchanek, Katarzyna; Simka, Wojciech

    2015-01-01

    Highlights: • Oxide layers prepared via PEO of zirconium were subjected to heat treatment. • Surface characteristics were determined for the obtained oxide coatings. • Heat treatment led to the partial destruction of the anodic oxide layer. • Pitting corrosion resistance of zirconium was improved after the modification. - Abstract: Herein, results of heat treatment of zirconium anodised under plasma electrolytic oxidation (PEO) conditions at 500–800 °C are presented. The obtained oxide films were investigated by means of SEM, XRD and Raman spectroscopy. The corrosion resistance of the zirconium specimens was evaluated in Ringer's solution. A bilayer oxide coatings generated in the course of PEO of zirconium were not observed after the heat treatment. The resulting oxide layers contained a new sublayer located at the metal/oxide interface is suggested to originate from the thermal oxidation of zirconium. The corrosion resistance of the anodised metal was improved after the heat treatment

  5. A novel eco-friendly technique for efficient control of lime water softening process.

    Science.gov (United States)

    Ostovar, Mohamad; Amiri, Mohamad

    2013-12-01

    Lime softening is an established type of water treatment used for water softening. The performance of this process is highly dependent on lime dosage. Currently, lime dosage is adjusted manually based on chemical tests, aimed at maintaining the phenolphthalein (P) and total (M) alkalinities within a certain range (2 P - M > or = 5). In this paper, a critical study of the softening process has been presented. It has been shown that the current method is frequently incorrect. Furthermore, electrical conductivity (EC) has been introduced as a novel indicator for effectively characterizing the lime softening process.This novel technique has several advantages over the current alkalinities method. Because no chemical reagents are needed for titration, which is a simple test, there is a considerable reduction in test costs. Additionally, there is a reduction in the treated water hardness and generated sludge during the lime softening process. Therefore, it is highly eco-friendly, and is a very cost effective alternative technique for efficient control of the lime softening process.

  6. Curvature Effect and the Spectral Softening Phenomenon Detected ...

    Indian Academy of Sciences (India)

    soft spectral evolution, indicating that this spectral softening is not a rare phenomenon .... of time, there exists a temporal steep decay phase accompanied by spectral softening. (d) In most cases, the temporal power law index α and the spectral.

  7. Softening behaviour of brown coal ashes. Influence of ash components and gas atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Hegermann, R; Huettinger, K J [Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Chemische Technik

    1990-03-01

    The softening behaviour of brown coal ashes during gasification is important for three reasons: (1) Formation of large agglomerates, (2) inactivation of catalytically active ash components, (3) encapsulation of parts of the coal. The softening behaviour of the ashes was studied with a high temperature dilatometer at ambient pressure in various atmospheres (air, CO{sub 2}, Ar/H{sub 2}O, Ar, H{sub 2}/H{sub 2}O, H{sub 2}) using a push-rod with a conical tip. The heating rate was 5 Kmin{sup -1}, the final temperature 1000deg C, the residence time 1 h. (orig.).

  8. New Nomenclatures for Heat Treatments of Additively Manufactured Titanium Alloys

    Science.gov (United States)

    Baker, Andrew H.; Collins, Peter C.; Williams, James C.

    2017-07-01

    The heat-treatment designations and microstructure nomenclatures for many structural metallic alloys were established for traditional metals processing, such as casting, hot rolling or forging. These terms do not necessarily apply for additively manufactured (i.e., three-dimensionally printed or "3D printed") metallic structures. The heat-treatment terminology for titanium alloys generally implies the heat-treatment temperatures and their sequence relative to a thermomechanical processing step (e.g., forging, rolling). These designations include: β-processing, α + β-processing, β-annealing, duplex annealing and mill annealing. Owing to the absence of a thermomechanical processing step, these traditional designations can pose a problem when titanium alloys are first produced via additive manufacturing, and then heat-treated. This communication proposes new nomenclatures for heat treatments of additively manufactured titanium alloys, and uses the distinct microstructural features to provide a correlation between traditional nomenclature and the proposed nomenclature.

  9. Thermoluminescent determination of prehistoric heat treatment of chert artifacts

    International Nuclear Information System (INIS)

    Melcher, C.L.; Zimmerman, D.W.

    1977-01-01

    In recent years archeologists have become interested in the extent to which prehistoric peoples heat-treated chert prior to shaping it into tools. Thermoluminescent determination of the radiation dose accumulated by an artifact since it was formed or last heated provides a simple, reliable test for such heat treatment. This test can be applied to single artifacts without the need for raw source material for comparison. Results on 25 artifacts from four sites indicate that, for many chert sources, color and luster are not useful indicators of heat treatment by prehistoric peoples

  10. Effect of heat treatment on workability of Cr-Ni-Mo steels

    International Nuclear Information System (INIS)

    Barcal, J.; Macek, K.

    1988-01-01

    The workability was studied of the new development generation of hardenable martensite Cr-Ni-Mo steels of the 10-10-2 and 6-11-3 types whose application is envisaged in future in nuclear engineering. Attention is paid to identification of inclusions and the phase analysis ofthe structure with respect to heat treatment and steel type. Face milling was used in the test of workability. In addition, tensile strength and impact bending strength testing was performed. The results showed that steel of the 6-11-3 type in the quenched condition was best workable. However, this steel showed a significant reduction in workability when in the hardened condition. Reduced workability can also be presumed for type 10-10-2 steel in the hardened condition when life is considered. Microstructure changes leading to softening of steel by aging had a favourable effect on workability, especially in steels of the 10-10-2 type. Hardened steels of the 6-11-3 type are recommended to be re-quenched. (Z.M.). 7 figs., 3 tabs., 9 refs

  11. Process for forming thin film, heat treatment process of thin film sheet, and heat treatment apparatus therefor

    International Nuclear Information System (INIS)

    Watanabe, S.

    1984-01-01

    The invention provides a process for forming a magnetic thin film on a base film, a heat treatment process of a thin film sheet consisting of the base film and the magnetic thin film, and an apparatus for performing heat treatment of the thin film sheet. Tension applied to the thin film sheet is substantially equal to that applied to the base film when the magnetic thin film is formed thereon. Then, the thin film sheet is treated with heat. The thin film sheet is heated with a given temperature gradient to a reactive temperature at which heat shrinkage occurs, while the tension is being applied thereto. Thereafter, the thin film sheet to which the tension is still applied is cooled with substantially the same temperature gradient as applied in heating. The heat treatment apparatus has a film driving unit including a supply reel, a take-up reel, a drive source and guide rollers; a heating unit including heating plates, heater blocks and a temperature controller for heating the sheet to the reactive temperature; and a heat insulating unit including a thermostat and another temperature controller for maintaining the sheet at the nonreactive temperature which is slightly lower than the reactive temperature

  12. A Study of Ballast Water Treatment Using Engine Waste Heat

    Science.gov (United States)

    Balaji, Rajoo; Yaakob, Omar; Koh, Kho King; Adnan, Faizul Amri bin; Ismail, Nasrudin bin; Ahmad, Badruzzaman bin; Ismail, Mohd Arif bin

    2018-05-01

    Heat treatment of ballast water using engine waste heat can be an advantageous option complementing any proven technology. A treatment system was envisaged based on the ballast system of an existing, operational crude carrier. It was found that the available waste heat could raise the temperatures by 25 °C and voyage time requirements were found to be considerable between 7 and 12 days to heat the high volumes of ballast water. Further, a heat recovery of 14-33% of input energies from exhaust gases was recorded while using a test rig arrangement representing a shipboard arrangement. With laboratory level tests at temperature ranges of around 55-75 °C, almost complete species mortalities for representative phytoplankton, zooplankton and bacteria were observed while the time for exposure varied from 15 to 60 s. Based on the heat availability analyses for harvesting heat from the engine exhaust gases(vessel and test rig), heat exchanger designs were developed and optimized using Lagrangian method applying Bell-Delaware approaches. Heat exchanger designs were developed to suit test rig engines also. Based on these designs, heat exchanger and other equipment were procured and erected. The species' mortalities were tested in this mini-scale arrangement resembling the shipboard arrangement. The mortalities realized were > 95% with heat from jacket fresh water and exhaust gases alone. The viability of the system was thus validated.

  13. Effect of heat treatment on carbon steel pipe welds

    International Nuclear Information System (INIS)

    Mohamad Harun.

    1987-01-01

    The heat treatment to improve the altered properties of carbon steel pipe welds is described. Pipe critical components in oil, gasification and nuclear reactor plants require adequate room temperature toughness and high strength at both room and moderately elevated temperatures. Microstructure and microhardness across the welds were changed markedly by the welding process and heat treatment. The presentation of hardness fluctuation in the welds can produce premature failure. A number of heat treatments are suggested to improve the properties of the welds. (author) 8 figs., 5 refs

  14. Ultrasonic evaluation of heat treatment for stress relief in steel

    International Nuclear Information System (INIS)

    Bittencourt, Marcelo de S.Q.; Lamy, Carlos A.; Goncalves Filho, Orlando J.A.; Payao Filho, Joao da C.

    2000-01-01

    Residual stresses in materials arise due to the manufacturing processes. As a consequence, in the nuclear area some components must suffer a stress relief treatment according to strict criteria. Although these treatments are carefully carried on, concern with nuclear safety is constantly growing. This work proposes a nondestructive ultrasonic method to guarantee the efficiency of the heat treatment. It was used a short peened steel plate with tensile and compressive stresses which was submitted to a stress relief treatment. The results show that the proposed ultrasonic method could be used to confirm the efficiency of the stress relief heat treatment. (author)

  15. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots

    NARCIS (Netherlands)

    Kok, H. Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D.; Stalpers, Lukas J. A.; Crezee, Johannes

    2017-01-01

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to

  16. Heat Transfer Analysis of Localized Heat-Treatment for Grade 91 Steel

    Science.gov (United States)

    Walker, Jacob D.

    Many of the projects utilizing Grade 91 steel are large in scale, therefore it is necessary to assemble on site. The assembly of the major pieces requires welding in the assembly; this drastically changes the superior mechanical properties of Grade 91 steel that it was specifically developed for. Therefore, because of the adverse effects of welding on the mechanical properties of Grade 91, it is necessary to do a localized post weld heat treatment. As with most metallic materials grade 91 steel requires a very specific heat treatment process. This process includes a specific temperature and duration at that temperature to achieve the heat treatment desired. Extensive research has been done to determine the proper temperatures and duration to provide the proper microstructure for the superior mechanical properties that are inherent to Grade 91 steel. The welded sections are typically large structures that require local heat treatments and cannot be placed in an oven. The locations of these structures vary from indoors in a controlled environment to outdoors with unpredictable environments. These environments can be controlled somewhat, however in large part the surrounding conditions are unchangeable. Therefore, there is a need to develop methods to accurately apply the surrounding conditions and geometries to a theoretical model in order to provide the proper requirements for the local heat treatment procedure. Within this requirement is the requirement to define unknowns used in the heat transfer equations so that accurate models can be produced and accurate results predicted. This study investigates experimentally and numerically the heat transfer and temperature fields of Grade 91 piping in a local heat treatment. The objective of this thesis research is to determine all of the needed heat transfer coefficients. The appropriate heat transfer coefficients are determined through the inverse heat conduction method utilizing a ceramic heat blanket. This will be done

  17. Examination of heat treatments at preservation of grape must

    Directory of Open Access Journals (Sweden)

    Péter Korzenszky

    2014-02-01

    Full Text Available Heat treatment is a well-known process in food preservation. It is made to avoid and to slow down food deterioration. The process was developed by Louise Pasteur French scientist to avoid late among others wine further fermentation. The different heat treatments influence the shelf life in food production. In our article we present the process of grape must fermentation, as grape must is the base material of wine production. The treatment of harvested fresh grape juice has a big influence on end product quality. It is our experiments we examined the same grape must with four different methods in closed and in open spaces to determine CO2 concentration change. There are four different methods for treatment of grape juice: boiling, microwave treatment, treatment by water bath thermostat and a control without treatment. As a result of the comparison it can be stated that the heat treatment delays the start of fermentation, thereby increasing shelf life of grape must. However, no significant differences were found between two fermentation of heat-treated grape must by the microwave and water-bath thermostat. The different heat treatment of grape must base materials was done at the laboratory in Faculty of Mechanical Engineering of Szent István University. The origin of the table grapes used for the examination was Gödöllő-hillside. Normal 0 21 false false false HU X-NONE X-NONE

  18. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    OpenAIRE

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-01-01

    Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in ...

  19. Softened food reduces weight loss in the streptozotocin-induced male mouse model of diabetic nephropathy

    DEFF Research Database (Denmark)

    Nørgaard, Sisse A; Sand, Fredrik W; Sørensen, Dorte B

    2018-01-01

    The streptozotocin (STZ)-induced diabetic mouse is a widely used model of diabetes and diabetic nephropathy (DN). However, it is a well-known issue that this model is challenged by high weight loss, which despite supportive measures often results in high euthanization rates. To overcome...... these issues, we hypothesized that supplementing STZ-induced diabetic mice with water-softened chow in addition to normal chow would reduce weight loss, lower the need for supportive treatment, and reduce the number of mice reaching the humane endpoint of 20% weight loss. In a 15 week STZ-induced DN study we...... demonstrated that diabetic male mice receiving softened chow had reduced acute weight loss following STZ treatment ( p = 0.045) and additionally fewer mice were euthanized due to weight loss. By supplementing the diabetic mice with softened chow, no mice reached 20% weight loss whereas 37.5% of the mice...

  20. Improved process for the treatment of bituminous materials. [two heat treatments

    Energy Technology Data Exchange (ETDEWEB)

    1947-04-30

    A continuous process for recovering valuable hydrocarbon oils from solid minerals adapted to produce such oils upon application of heat, consists of reducing the raw minerals to a powder, suspending the powdered minerals in a gaseous medium and subjecting the suspension thus formed to heat treatment in a primary reaction zone, followed by heat treatment in a secondary reaction zone separate from the primary reaction zone. The temperature during the second of said treatments being substantially higher than that of the first.

  1. Heat treatment of cathodic arc deposited amorphous hard carbon films

    Energy Technology Data Exchange (ETDEWEB)

    Anders, S.; Ager, J.W. III; Brown, I.G. [and others

    1997-02-01

    Amorphous hard carbon films of varying sp{sup 2}/sp{sup 3} fractions have been deposited on Si using filtered cathodic are deposition with pulsed biasing. The films were heat treated in air up to 550 C. Raman investigation and nanoindentation were performed to study the modification of the films caused by the heat treatment. It was found that films containing a high sp{sup 3} fraction sustain their hardness for temperatures at least up to 400 C, their structure for temperatures up to 500 C, and show a low thickness loss during heat treatment. Films containing at low sp{sup 3} fraction graphitize during the heat treatment, show changes in structure and hardness, and a considerable thickness loss.

  2. Effect of heat-treatment on elevated temperature fatigue-crack growth behavior of two heats of Alloy 718

    International Nuclear Information System (INIS)

    Mills, W.J.; James, L.A.

    1978-05-01

    The room temperature and elevated temperature fatigue-crack growth behavior of two heats of Alloy 718 was characterized within a linear-elastic fracture mechanics framework. Two different heat-treatments were used: the ''conventional'' (ASTM A637) treatment, and a ''modified'' heat-treatment designed to improve the toughness of Alloy 718 base metal and weldments. Heat-to-heat variations in the fatigue-crack propagation behavior were observed in the conventionally-treated material. On the other hand, no heat-to-heat variations were observed in the modified condition. Furthermore, both heats of Alloy 718 exhibited superior fatigue-crack growth resistance when given the modified heat-treatment. Electron fractographic examination of Alloy 718 fatigue fracture surfaces revealed that the operative crack growth mechanisms were dependent on heat-treatment, temperature, and ΔK level

  3. Effect of heat moisture treatment and annealing on physicochemical ...

    African Journals Online (AJOL)

    Red sorghum starch was physically modified by annealing and heat moisture treatment. The swelling power and solubility increased with increasing temperature range (60-90°), while annealing and heatmoisture treatment decreased swelling power and solubility of starch. Solubility and swelling were pH dependent with ...

  4. Softened food reduces weight loss in the streptozotocin-induced male mouse model of diabetic nephropathy.

    Science.gov (United States)

    Nørgaard, Sisse A; Sand, Fredrik W; Sørensen, Dorte B; Abelson, Klas Sp; Søndergaard, Henrik

    2018-01-01

    The streptozotocin (STZ)-induced diabetic mouse is a widely used model of diabetes and diabetic nephropathy (DN). However, it is a well-known issue that this model is challenged by high weight loss, which despite supportive measures often results in high euthanization rates. To overcome these issues, we hypothesized that supplementing STZ-induced diabetic mice with water-softened chow in addition to normal chow would reduce weight loss, lower the need for supportive treatment, and reduce the number of mice reaching the humane endpoint of 20% weight loss. In a 15 week STZ-induced DN study we demonstrated that diabetic male mice receiving softened chow had reduced acute weight loss following STZ treatment ( p = 0.045) and additionally fewer mice were euthanized due to weight loss. By supplementing the diabetic mice with softened chow, no mice reached 20% weight loss whereas 37.5% of the mice without this supplement reached this humane endpoint ( p = 0.0027). Excretion of corticosterone metabolites in faeces was reduced in diabetic mice on softened chow ( p = 0.0007), suggesting lower levels of general stress. Finally, it was demonstrated that the water-softened chow supplement did not significantly affect the induction of key disease parameters, i.e. %HbA1C and albuminuria nor result in abnormal teeth wear. In conclusion, supplementation of softened food is refining the STZ-induced diabetic mouse model significantly by reducing stress, weight loss and the number of animals sacrificed due to humane endpoints, while maintaining the key phenotypes of diabetes and nephropathy.

  5. Hypoxia-responsive ERFs involved in postdeastringency softening of persimmon fruit.

    Science.gov (United States)

    Wang, Miao-Miao; Zhu, Qing-Gang; Deng, Chu-Li; Luo, Zheng-Rong; Sun, Ning-Jing; Grierson, Donald; Yin, Xue-Ren; Chen, Kun-Song

    2017-11-01

    Removal of astringency by endogenously formed acetaldehyde, achieved by postharvest anaerobic treatment, is of critical importance for many types of persimmon fruit. Although an anaerobic environment accelerates de-astringency, it also has the deleterious effect of promoting excessive softening, reducing shelf life and marketability. Some hypoxia-responsive ethylene response factors (ERFs) participate in anaerobic de-astringency, but their role in accelerated softening was unclear. Undesirable rapid softening induced by high CO 2 (95%) was ameliorated by adding the ethylene inhibitor 1-MCP (1 μL/L), resulting in reduced astringency while maintaining firmness, suggesting that CO 2 -induced softening involves ethylene signalling. Among the hypoxia-responsive genes, expression of eight involved in fruit cell wall metabolism (Dkβ-gal1/4, DkEGase1, DkPE1/2, DkPG1, DkXTH9/10) and three ethylene response factor genes (DkERF8/16/19) showed significant correlations with postdeastringency fruit softening. Dual-luciferase assay indicated that DkERF8/16/19 could trans-activate the DkXTH9 promoter and this interaction was abolished by a mutation introduced into the C-repeat/dehydration-responsive element of the DkXTH9 promoter, supporting the conclusion that these DkERFs bind directly to the DkXTH9 promoter and regulate this gene, which encodes an important cell wall metabolism enzyme. Some hypoxia-responsive ERF genes are involved in deastringency and softening, and this linkage was uncoupled by 1-MCP. Fruit of the Japanese cultivar 'Tonewase' provide a model for altered anaerobic response, as they lost astringency yet maintained firmness after CO 2 treatment without 1-MCP and changes in cell wall enzymes and ERFs did not occur. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  6. Evaluation of the impact of lime softening waste disposal in natural environments

    Science.gov (United States)

    Drinking water treatment residues (WTR), generated from the lime softening processes, are commonly reused or disposed of in a number of applications; these include use as a soil amendment or a subsurface fill. Recently questions were posed by the Florida regulatory community on w...

  7. ARSENIC REMOVAL FROM DRINKING WATER BY COAGULATION/FILTRATION AND LIME SOFTENING PLANTS

    Science.gov (United States)

    This report documents a long term performance (one year) study of 3 water treatment plants to remove arsenic from drinking water sources. The 3 plants consisted of 2 conventional coagulation/filtration plants and 1 lime softening plant. The study involved the collecting of weekly...

  8. First order reversal curve analysis on NdFeB nanocomposite ribbons subjected to Joule heating treatments

    Energy Technology Data Exchange (ETDEWEB)

    Pampillo, L.G. [INTECIN-Instituto de Tecnologias y ciencias de la Ingenieria ' Hilario Fernandez Long' (UBA-CONICET), Facultad de Ingenieria, Paseo Colon 850 (C1063ACV), C. A. B. A. (Argentina); Saccone, F.D., E-mail: fsaccone@fi.uba.ar [INTECIN-Instituto de Tecnologias y ciencias de la Ingenieria ' Hilario Fernandez Long' (UBA-CONICET), Facultad de Ingenieria, Paseo Colon 850 (C1063ACV), C. A. B. A. (Argentina); Knobel, M. [Instituto de Fisica Gleb Wataghin-Departamento de Fisica de Materia Condensada-Universidade Estadual de Campinas, Cidade Universitaria Zeferino Vaz, Barao Geraldo 13083-970, Campinas, Sao Paulo (Brazil); Sirkin, H.R.M. [INTECIN-Instituto de Tecnologias y ciencias de la Ingenieria ' Hilario Fernandez Long' (UBA-CONICET), Facultad de Ingenieria, Paseo Colon 850 (C1063ACV), C. A. B. A. (Argentina)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Nd-lean amorphous precursors subjected to Joule heating. Black-Right-Pointing-Pointer Exchange-spring magnets. Black-Right-Pointing-Pointer FORC diagrams of irreversible switching fields. Black-Right-Pointing-Pointer This last techniques helped us to verify the optimized treatments conditions. - Abstract: Amorphous precursors with composition Nd{sub 4.5}Fe{sub 72-x}Co{sub 3+x}Cr{sub 2}Al{sub 1}B{sub 17.5} (x = 0, 2, 7, 12) were thermally treated by the Joule heating technique with a linearly varying electrical current. The crystallization kinetics was followed by monitoring the resistance of the ribbons during the heating up to the final applied current. Crystallized nanostructured phases coexist with an amorphous matrix, as it was observed by means of Moessbauer Spectroscopy and X-ray diffraction. The irreversible magnetic response of the Joule heated ribbons was analyzed by the First Order Reversal Curves (FORC) diagram technique. For the optimal treatments, associated with the higher maximum energy products for each sample composition, it was found that the main interaction is of a strongly dipolar characteristic. Over annealed samples show a FORC diagram that gives into account of softening, due to grain growth, for those phases precipitated at the first crystallization stage. When it is measured at 20 K, the hardest magnetic sample (Fe = 72 at.%, Co = 3 at.%, I{sub final} = 0.5 A), exhibits a diagram with characteristics corresponding to dipolar interactions of soft phases. This fact is consistent with an enhancement of the exchange length due to the increase in the soft phase stiffness as it is expected at low temperatures.

  9. Irradiation in combination of heat treatment of mango puree

    International Nuclear Information System (INIS)

    Noomhorm, A.; Apintanapong, M.

    1996-01-01

    The effect of irradiation with heat combination treatment on the shelf life and quality of mango puree was studied. Thermal inactivation of polyphenol oxidase enzyme at 80 degree C and 15 min. was used as a measure of adequacy of pre-heat treatment. Irradiation of mango puree after heat treatment at dosage of 0, 2, 4, 6 and 8 kGy showed no change in mc, pH, acidity, and TSS but during storage, growth of microorganisms brought changes in these values. Irradiation in combination with low temperature (5 degree C) reduced discoloration and darkening rate during storage. Irradiation dose from 0 to 8 kGy resulted in log linear reductions in microorganism levels but at 6 and 8 kGy, there was no growth of microorganisms. Products irradiated at 8 kGy showed no microorganism growth at both temperatures

  10. Softening during deformation of Zr alloys

    International Nuclear Information System (INIS)

    Kral, R.; Trojanova, Z.; Lukac, P.

    1994-01-01

    The strain hardening behaviour is described by the work hardening rate. The work hardening rate depends on the dislocation density changes which result from the competition between the rate of dislocation storage and the rate of annihilation of dislocations. In the present work the deformation behaviour of Zr-based alloys is investigated. From the stress-strain curves the work hardening rate is calculated and its stress dependence is studied at various temperatures between 300 and 1000 K. Experimental investigations show that at first the work hardening rate decreases quasi-linearly with increasing stress. After a certain stress is reached, the work hardening rate decreases more slowly with increasing stress. We discuss the influence of hardening and softening processes on the deformation behaviour. Analytical models are compared with experimental results. (orig.)

  11. Using geothermal energy to heat a portion of a formation for an in situ heat treatment process

    Science.gov (United States)

    Pieterson, Roelof; Boyles, Joseph Michael; Diebold, Peter Ulrich

    2010-06-08

    Methods of using geothermal energy to treat subsurface formations are described herein. Methods for using geothermal energy to treat a subsurface treatment area containing or proximate to hydrocarbons may include producing geothermally heated fluid from at least one subsurface region. Heat from at least a portion of the geothermally heated fluid may be transferred to the subsurface treatment area to heat the subsurface treatment area. At least some hydrocarbon fluids may be produced from the formation.

  12. Desensitization of stainless steels by laser surface heat-treatment

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Yoshikuni; Nishimoto, Kazutoshi

    1987-11-01

    Laser heating was applied for the desensitization heat-treatment of the surface layer in the sensitized HAZ of Type 304 stainless steel. The degree of sensitization was examined by EPR technique and the 10 % oxalic acid electrolytic etch test. The CO/sub 2/ laser with maximum power of 1.5 kW was used for heat-treatment. Time-Temperature-Desensitization diagram (TTDS diagram) for sensitized Type 304 stainless steels were developed by calculation assuming the chromium diffusion control for desensitization which might occur when the chromium depleted zone was healed up due to dissolution of chromium carbide and chromium diffusion from the matrix being heated at the solution annealing temperatures. TTDS diagrams calculated agree fairly well with ones determined by corrosion tests. Laser irradiation conditions (e.g., Laser power, beam diameter and traveling velocity) required for desensitization of sensitized Type 304 stainless steels were calculated using additivity rule from the TTDS diagram calculated and theoretical thermal curve of laser heating derived from the heat conduction theory. After laser beam irradiated under an optimum condition predicted by calculation, the sensitized HAZ of Type 304 stainless steel restored complete resistance to intergranular corrosion.

  13. Impact Toughness and Heat Treatment for Cast Aluminum

    Science.gov (United States)

    Lee, Jonathan A (Inventor)

    2016-01-01

    A method for transforming a cast component made of modified aluminum alloy by increasing the impact toughness coefficient using minimal heat and energy. The aluminum alloy is modified to contain 0.55%-0.60% magnesium, 0.10%-0.15% titanium or zirconium, less than 0.07% iron, a silicon-tomagnesium product ratio of 4.0, and less than 0.15% total impurities. The shortened heat treatment requires an initial heating at 1,000deg F. for up to I hour followed by a water quench and a second heating at 350deg F. to 390deg F. for up to I hour. An optional short bake paint cycle or powder coating process further increase.

  14. EFFECT OF HEAT TREATMENT ON SOYBEAN PROTEIN SOLUBILITY

    Directory of Open Access Journals (Sweden)

    RODICA CĂPRIŢĂ

    2007-05-01

    Full Text Available The use of soybean products in animal feeds is limited due to the presence of antinutritional factors (ANF. Proper heat processing is required to destroy ANF naturally present in raw soybeans and to remove solvent remaining from the oil extraction process. Over and under toasting of soybean causes lower nutritional value. Excessive heat treatment causes Maillard reaction which affects the availability of lysine in particular and produces changes to the chemical structure of proteins resulting in a decrease of the nutritive value. The objective of this study was to evaluate the effect of heating time on the protein solubility. The investigation of the heating time on protein solubility in soybean meal (SBM revealed a negative correlation (r = -0.9596. Since the urease index is suitable only for detecting under processed SBM, the protein solubility is an important index for monitoring SBM quality.

  15. Heat treatment effect on ductility of nickel-base alloys

    International Nuclear Information System (INIS)

    Burnakov, K.K.; Khasin, G.A.; Danilov, V.F.; Oshchepkov, B.V.; Listkova, A.I.

    1979-01-01

    Causes of low ductility of the KhN75MBTYu and KhN78T alloys were studied along with the heat treatment effects. Samples were tested at 20, 900, 1100, 1200 deg C. Large amount of inclusions was found in intercrystalline fractures of the above low-ductile alloys. The inclusions of two types took place: (α-Al 2 O 3 , FeO(Cr 2 O 3 xAl 2 O 3 )) dendrite-like ones and large-size laminated SiO 2 , FeO,(CrFe) 2 O 3 inclusions situated as separate colonies. Heat treatment of the alloys does not increase high-temperature impact strength and steel ductility. The heating above 1000 deg C leads to a partial dissolution and coagulation of film inclusions which results in an impact strength increase at room temperature

  16. Effect of heat treatment on brewer's yeast fermentation activity

    OpenAIRE

    Kharandiuk, Tetiana; Kosiv, Ruslana; Palianytsia, Liubov; Berezovska, Natalia

    2015-01-01

    The influence of temperature treatment of brewer's yeast strain Saflager W-34/70 at temperatures of -17, 20, 25, 30, 35, 40 °C on their fermentative activity was studied. It was established that the freezing of yeast leads to a decrease of fermentation activity in directly proportional to the duration way. Fermentative activity of yeast samples can be increased by 20-24% by heat treatment at 35 °C during 15-30 minutes.

  17. Evaluation of hardening and softening behaviors in Zn–21Al–2Cu alloy processed by equal channel angular pressing

    Directory of Open Access Journals (Sweden)

    José Luis Hernández-Rivera

    2017-10-01

    Full Text Available The microstructural evolution of as-cast and homogenized Zn–21Al–2Cu samples after two and six passes in an equal channel angular pressing (ECAP at room temperature was reported. A homogenization treatment for 24 h at 350 °C was applied to the as-cast samples followed by deformation. An annealing heat treatment was performed on all samples after the ECAP process. Our results showed that the homogenized and deformed samples displayed a uniform fine-grained microstructure after annealing, while as-cast samples without homogenization treatment presented only some regions of fine-grained microstructure. The level of microsegregation was higher in the as-cast samples as compared to the homogenized ones even after annealing. Vickers microhardness measurement on samples after deformation is smaller than the original material indicating a softening. However, after the annealing treatment, the microhardness increased, indicating that there was a slight hardening of the material. Keywords: Severe plastic deformation, ECAP, Work softening, Annealing, Hardening, Fine grain

  18. Heat treatment effect on impact strength of 40Kh steel

    International Nuclear Information System (INIS)

    Golubev, V.K.; Novikov, S.A.; Sobolev, Yu.S.; Yukina, N.A.

    1984-01-01

    The paper presents results of studies on the effect of heat treatment on strength and pattern of 40Kh steel impact failure. Loading levels corresponding to macroscopic spalling microdamage initiation in the material are determined for three initial states. Metallographic study on the spalling failure pattern for 40Kh steel in different initial states and data on microhardness measurement are presented

  19. Influence of heat treatment temperature on bonding and oxidation ...

    Indian Academy of Sciences (India)

    The effects of heat treatment temperature on the morphology, composition, chemical bonds, oxidation resistance and compressive strength of diamond particles coated with TiO2 films were characterized through scanning electron microscopy, Fourier transform infrared, Raman spectroscopy, X-ray diffraction analysis, X-ray ...

  20. Influence of heat treatment temperature on bonding and oxidation ...

    Indian Academy of Sciences (India)

    Administrator

    Diamond; TiO2 film; heat treatment temperature; anti-oxidation; mechanical properties. 1. Introduction. Due to its ..... figure 4a, which was due to the change of chemical envi- ronment of ... graphite, diamond, diamond-like carbon and carbon.10.

  1. The effects of heat treatment on physical and technological ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... ween 450 and 660 m altitudes in Cide-Sehdagi (Gercek et al., 1998; Dogu ... changes continue as the temperature is increased in ... Heat treatment slows water uptake and wood cell wall absorbs ...... The Effect of Boiling Time.

  2. The effects of heat treatment on physical and technological ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... surface of wood were used to evaluate the effect of heat treatment on the surface characteristics of ... Some of the products developed by thermal treat- .... boards were stored uncontrolled condition in an unheated room for .... These results can be explained with material loses in ...... Finland-state of the art.

  3. Application of microjet in heat treatment of aluminium bronzes

    Directory of Open Access Journals (Sweden)

    Z. Górny

    2011-04-01

    Full Text Available Mechanical properties of a CuAl10Fe4Ni4 bronze subjected to solution heat treatment and toughening were examined. In solution heattreatment, a microjet was used to raise the cooling rate. A slight increase of mechanical properties was observed.

  4. THE EFFECTS OF INTERCRITICAL HEAT TREATMENTS ON THE ...

    African Journals Online (AJOL)

    Effect of intercritical heat treatment on 0.14wt%C 0.56wt%Mn 0.13wt%Si struc- ... Table 1: Chemical composition of the steel used (wt. %) with its critical temperature (calculated). C. Mn. Si. Ni. S ... primary austenitic grain size hardening and.

  5. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    Effect of heat treatment (55°C/20 min) on polyphenol oxidase (PPO) and peroxidase (POD) activities and total phenolic compounds was investigated in Algerian dates (Deglet Nour variety) at Tamar (fully ripe) stage and in dates stored for 5 months at ambient temperature and in cold storage (10°C). Results obtained ...

  6. Laser heat treatment of welds for various stainless steels

    Science.gov (United States)

    Dontu, O.; Ganatsios, S.; Alexandrescu, N.; Predescu, C.

    2008-03-01

    The paper presents a study concerning the post - weld heat treatment of a duplex stainless steel. Welded joint samples were surface - treated using the same laser source adopted during welding in order to counterbalance the excess of ferrite formed in the welding process.

  7. Effects of heat treatment on density, dimensional stability and color ...

    African Journals Online (AJOL)

    The purpose of this study was to evaluate the effect of heat treatment on some physical properties and color change of Pinus nigra wood which has high industrial use potential and large growing stocks in Turkey. Wood samples which comprised the material of the study were obtained from an industrial plant. Samples were ...

  8. Heat treatment giving a stable high temperature micro-structure in cast austenitic stainless steel

    Science.gov (United States)

    Anton, Donald L.; Lemkey, Franklin D.

    1988-01-01

    A novel micro-structure developed in a cast austenitic stainless steel alloy and a heat treatment thereof are disclosed. The alloy is based on a multicomponent Fe-Cr-Mn-Mo-Si-Nb-C system consisting of an austenitic iron solid solution (.gamma.) matrix reinforced by finely dispersed carbide phases and a heat treatment to produce the micro-structure. The heat treatment includes a prebraze heat treatment followed by a three stage braze cycle heat treatment.

  9. A new paradigm for heat treatment of alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ustinovshikov, Y., E-mail: ust@ftiudm.ru

    2014-11-25

    Highlights: • The sign of the ordering energy in alloys varies with the temperature. • Each temperature of heating leads to formation of its characteristic microstructure. • Quenching of alloys is a totally unnecessary and useless operation. - Abstract: The article considers the consequences in the field of heat treatment of alloys that could follow the introduction of the concept of phase transition ordering-phase separation into common use. By example of the Fe{sub 50}Cr{sub 50} alloy, industrial carbon tool steel and Ni{sub 88}Al{sub 12} alloy, it is shown that this transition occurs at a temperature, which is definite for each system, that the change of the sign of the chemical interaction between component atoms reverses the direction of diffusion fluxes in alloys, which affects changes in the type of microstructures. The discovery of this phase transition dramatically changes our understanding of the solid solution, changes the ideology of alloy heat treatment. It inevitably leads to the conclusion about the necessity of carrying out structural studies with the help of TEM in order to adjust the phase diagrams of the systems where this phase transition has been discovered. Conclusions have been made that quenching of alloys from the so-called region of the solid solution, which is usually performed before tempering (aging) is a completely unnecessary and useless operation, that the final structure of the alloy is formed during tempering (aging) no matter what the structure was before this heat treatment.

  10. Sour gas injection for use with in situ heat treatment

    Science.gov (United States)

    Fowler, Thomas David [Houston, TX

    2009-11-03

    Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for providing acidic gas to a subsurface formation is described herein. The method may include providing heat from one or more heaters to a portion of a subsurface formation; producing fluids that include one or more acidic gases from the formation using a heat treatment process. At least a portion of one of the acidic gases may be introduced into the formation, or into another formation, through one or more wellbores at a pressure below a lithostatic pressure of the formation in which the acidic gas is introduced.

  11. Novel magnetic heating probe for multimodal cancer treatment.

    Science.gov (United States)

    Kan-Dapaah, Kwabena; Rahbar, Nima; Soboyejo, Wole

    2015-05-01

    Multifunctional materials consisting of polymers and magnetic nanoparticles (MNPs) are highly sought after in the field of biomedical engineering. These materials offer new opportunities for the development of novel cancer treatment modalities that can increase the efficacy of cancer therapy. In this paper, a novel probe for multimodal cancer treatment is proposed and analyzed. The probe is essentially a cannula with two main parts: a distal heat generating tip made of a magnetic nanocomposite and a proximal insulated shaft. A description of the concept and functional operations of the probe is presented. In an effort to assess its feasibility, the authors evaluated the ability of probe tip (made of PMMA-Fe3O4 nanocomposite) to generate heat in biological tissue using alternating magnetic field (AMF) parameters (field strength and frequency) that are acceptable for human use. Heat generation by MNPs was determined using the linear response theory. The effects of Fe3O4 volume fraction on heat generation as well as treatment time on the thermal dose were studied. The finite element method model was tested for its validity using an analytical model. Lesions were revealed to have an ellipsoidal shape and their sizes were affected by treatment time. However, their shapes remained unchanged. The comparison with the analytical model showed reasonably a good agreement to within 2%. Furthermore, the authors' numerical predictions also showed reasonable agreement with the experimental results previously reported in the literature. The authors' predictions demonstrate the feasibility of their novel probe to achieve reasonable lesion sizes, during hyperthermic or ablative heating using AMF parameters (field strength and frequency) that are acceptable for human use.

  12. Comparative study of heat transfer and wetting behaviour of conventional and bioquenchants for industrial heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Peter; Prabhu, K. Narayan [Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal, P.O. Srinivasnagar 575 025 Mangalore, Karnataka State (India)

    2008-02-15

    An investigation was conducted to study the suitability of vegetable oils as bioquenchants for industrial heat treatment. The study involved the assessment of the severity of quenching and wetting behaviour of conventional and vegetable oil quench media. Quench severities of sunflower, coconut and palm oils were found to be greater than mineral oil. The quench severity of aqueous media is greater than oil media although their wettability is poor as indicated by their higher contact angles. A dimensionless contact angle parameter defined in this work is found to be a better parameter to compare the wetting behaviour with heat transfer. (author)

  13. Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment

    Science.gov (United States)

    Baars, Destiny L.; Pelegri, Francisco

    2016-01-01

    Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, specifically the generation of homozygous gynogenetic diploids is useful in genetic analysis because it allows the direct production of homozygotes from a single heterozygous mother. This article describes a modified protocol for ploidy duplication based on a heat pulse during the first cell cycle, Heat Shock 2 (HS2). Through inhibition of centriole duplication, this method results in a precise cell division stall during the second cell cycle. The precise one-cycle division stall, coupled to unaffected DNA duplication, results in whole genome duplication. Protocols associated with this method include egg and sperm collection, UV treatment of sperm, in vitro fertilization and heat pulse to cause a one-cell cycle division delay and ploidy duplication. A modified version of this protocol could be applied to induce ploidy changes in other animal species. PMID:28060351

  14. Grain Refinement of Low Carbon Martensitic Steel by Heat Treatment

    Directory of Open Access Journals (Sweden)

    N. V. Kolebina

    2015-01-01

    Full Text Available The low-carbon steels have good corrosion and technological properties. Hot deformation is the main operation in manufacturing the parts from these steels. So one of the important properties of the material is a property of plasticity. The grain size significantly influences on the ductility properties of steel. The grain size of steel depends on the chemical composition of the crystallization process, heat treatment, and steel machining. There are plenty methods to have grain refinement. However, taking into account the large size of the blanks for the hydro turbine parts, the thermal cycling is an advanced method of the grain refinement adaptable to streamlined production. This work experimentally studies the heat treatment influence on the microstructure of the low-carbon 01X13N04 alloy steel and proposes the optimal regime of the heat treatment to provide a significantly reduced grain size. L.M. Kleiner, N.P. Melnikov and I.N. Bogachyova’s works focused both on the microstructure of these steels and on the influence of its parameters on the mechanical properties. The paper focuses mainly on defining an optimal regime of the heat treatment for grain refinement. The phase composition of steel and temperature of phase transformation were defined by the theoretical analysis. The dilatometric experiment was done to determine the precise temperature of the phase transformations. The analysis and comparison of the experimental data with theoretical data and earlier studies have shown that the initial sample has residual stress and chemical heterogeneity. The influence of the heat treatment on the grain size was studied in detail. It is found that at temperatures above 950 ° C there is a high grain growth. It is determined that the optimal number of cycles is two. The postincreasing number of cycles does not cause further reducing grain size because of the accumulative recrystallization process. Based on the results obtained, the thermal cycling

  15. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    Directory of Open Access Journals (Sweden)

    Laura D'Evoli

    2013-07-01

    Full Text Available Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g. Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (−17%, while for lutein it was greater in the pulp fraction (−25%. Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (−36%. The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  16. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes.

    Science.gov (United States)

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-07-31

    Tomatoes and tomato products are rich sources of carotenoids-principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g). Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (-17%), while for lutein it was greater in the pulp fraction (-25%). Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (-36%). The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  17. Heat treatments of TiAl-Cr-V casting alloy

    International Nuclear Information System (INIS)

    Pu, Z.J.; Ma, J.L.; Wu, K.H.

    1995-01-01

    The need to investigate various kinds of fine microstructure based on casting TiAl alloy led to development of a multiple-stage heat treatment procedure. The first stage required the transformation of as-cast lamellar structure into near-gamma structure, followed by required transformation of near-gamma structure into various kinds of fine microstructure. The as-cast lamellar structure can be changed into near-gamma structure by annealing the alloy at 1,200 C for at least 50 hours. During the annealing process, two mechanisms are involved in transforming the lamellar structure into a near-gamma structure. One is the discontinuous coarsening (DC) process, and the other is the continuous coarsening (CC) process. With the near-gamma structure as an initial structure, the alloy being heat-treated in the γ + α and in the α fields can produce various kinds of microstructure with fine grain size. These microstructure significantly differ from the microstructure produced by heat-treating the deformed lamellar structure. Results of the investigation show that careful control of the time of the heat-treatment process in the single a field can produce a fine fully lamellar structure

  18. The heat treatment of steel. A mathematical control problem

    Energy Technology Data Exchange (ETDEWEB)

    Hoemberg, Dietmar; Kern, Daniela

    2009-07-21

    The goal of this paper is to show how the heat treatment of steel can be modelled in terms of a mathematical optimal control problem. The approach is applied to laser surface hardening and the cooling of a steel slab including mechanical effects. Finally, it is shown how the results can be utilized in industrial practice by a coupling with machine-based control. (orig.)

  19. Deep heat muscle treatment: A mathematical model - I

    International Nuclear Information System (INIS)

    Ogulu, A.; Bestman, A.R.

    1992-03-01

    The flow of blood during deep heat muscle treatment is studied in this paper. We model the blood vessel as a long tube in circular section whose radius varied slowly. Under the Boussinesq approximation, we seek asymptotic series expansions for the velocity components, temperature and pressure about a small parameter, ε, characterizing the radius variation. The study reveals mathematically why physicians recommend a hot bath for cuts and physiotherapists use ice packs for bruises. (author). 5 refs, 3 figs

  20. Microwave heat treatment as a substitute for conventional treatment of palm oil fruits

    International Nuclear Information System (INIS)

    Mujahid H Al-Fayadh; Nor Azura Masabbir Ali

    1996-01-01

    Microwave energy has become a sound method of heat treatment because of its high penetration power, cleanliness and possible economic significance. In this research, microwave heat was used as a substitute for conventional blanching method of palm oil fruits. Microwave treatment at 2450 MHz and 800 watts gave very close color and frn,frying characteristics to oil of blanched fruits after one minute exposure time. However, five minutes of microwave heat gave severe husk oil discoloration after 49 hours of deep frying, compared to all oils extracted from fruits treated by either low, microwave exposure time or conventional steam treatment. Kernel oil, after five minutes of microwave treatment, was less discolored than both steam or microwave-treated fruits for one minute. More carotenes and discoloration compounds may be contributed to discoloration during microwave treatments. Oil chemical constants of both husk and kernel oils treated by microwave heat were close to those treated by conventional heat. Further research is needed to investigate detailed oil characteristics and evaluate the feasibility study for using microwave energy, as a substitute for conventional heat in palm oil industry

  1. Simulations of Precipitate Microstructure Evolution during Heat Treatment

    Science.gov (United States)

    Wu, Kaisheng; Sterner, Gustaf; Chen, Qing; Jou, Herng-Jeng; Jeppsson, Johan; Bratberg, Johan; Engström, Anders; Mason, Paul

    Precipitation, a major solid state phase transformation during heat treatment processes, has for more than one century been intensively employed to improve the strength and toughness of various high performance alloys. Recently, sophisticated precipitation reaction models, in assistance with well-developed CALPHAD databases, provide an efficient and cost-effective way to tailor precipitate microstructures that maximize the strengthening effect via the optimization of alloy chemistries and heat treatment schedules. In this presentation, we focus on simulating precipitate microstructure evolution in Nickel-base superalloys under arbitrary heat treatment conditions. The newly-developed TC-PRISMA program has been used for these simulations, with models refined especially for non-isothermal conditions. The effect of different cooling profiles on the formation of multimodal microstructures has been thoroughly examined in order to understand the underlying thermodynamics and kinetics. Meanwhile, validations against several experimental results have been carried out. Practical issues that are critical to the accuracy and applicability of the current simulations, such as modifications that overcome mean-field approximations, compatibility between CALPHAD databases, selection of key parameters (particularly interfacial energy and nucleation site densities), etc., are also addressed.

  2. THE HEAT TREATMENT ANALYSIS OF E110 CASE HARDENING STEEL

    Directory of Open Access Journals (Sweden)

    MAJID TOLOUEI-RAD

    2016-03-01

    Full Text Available This paper investigates mechanical and microstructural behaviour of E110 case hardening steel when subjected to different heat treatment processes including quenching, normalizing and tempering. After heat treatment samples were subjected to mechanical and metallographic analysis and the properties obtained from applying different processes were analysed. The heat treatment process had certain effects on the resultant properties and microstructures obtained for E110 steel which are described in details. Quenching produced a martensitic microstructure characterized by significant increase in material’s hardness and a significant decreased in its impact energy. Annealed specimens produced a coarse pearlitic microstructure with minimal variation in hardness and impact energy. For normalized samples, fine pearlitic microstructure was identified with a moderate increase in hardness and significant reduction in impact energy. Tempering had a significant effect on quenched specimens, with a substantial rise in material ductility and reduction of hardness with increasing tempering temperature. Furthermore, Results provide additional substantiation of temper embrittlement theory for low-carbon alloys, and indicate potential occurrence of temper embrittlement for fine pearlitic microstructures.

  3. Heat treatment trials for ITER toroidal field coils

    International Nuclear Information System (INIS)

    Matsui, Kunihiro; Hemmi, Tsutomu; Koizumi, Norikiyo; Nakajima, Hideo; Kimura, Satoshi; Nakamoto, Kazunari

    2012-01-01

    Cable-in-conduit (CIC) conductors using Nb 3 Sn strands are used in ITER toroidal fields (TF) coils. Heat treatment generates thermal strain in CIC conductors because of the difference in thermal expansion between the Nb 3 Sn strands and the stainless-steel jacket. The elongation/shrinkage of the TF conductor may make it impossible to insert a wound TF conductor into the groove of a radial plate. In addition, it is expected that the deformation of the winding due to heat treatment-based release of the residual force in the jacket may also make it impossible to insert the winding in the groove, and that correcting the winding geometry to allow insertion of the winding may influence the superconducting performance of the TF conductor. The authors performed several trials using heat treatment as the part of activities in Phase II of TF coil procurement aiming to resolve the above-mentioned technical issues, and evaluated the elongations of 0.064, 0.074 and 0.072% for the straight and curved conductors and 1/3-scale double-pancake (DP) winding, respectively. It was confirmed that correction if the deformed winding did not influence the superconducting performance of the conductor. (author)

  4. Uninterrupted heat-treatment of starch raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Bronshtein, D Z

    1958-01-01

    A setup is presented, with a Rekord grinder, a Khronos scale, and other equipment of Soviet manufacture, in which oats, rye, wheat, and other grains are treated at 42 to 45 degrees prior to their use as raw materials in the ethanol industry. These materials are analyzed with respect to H/sub 2/O, starch, bulk, weight, screen analysis, and the final ethanol yields/ton of such raw materials. In a three year run in plant, this heat-treatment was advantageous, as compared to the former treatment of the starch materials.

  5. Uninterrupted heat-treatment of starch raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Bronshtein, D Z

    1958-01-01

    A setup is presented, with a Rekord grinder, a Khronos scale, and other equipment of Soviet manufacture, in which oats, rye, wheat, and other grains are treated at 42 to 45/sup 0/ prior to their use as raw materials in the ethanol industry. These materials are analyzed with respect to H/sub 2/O, starch, bulk weight, screen analysis, and the final ethanol yields/ton of such raw materials. In a three year run in a plant, this heat-treatment was advantageous, as compared to the former treatment of the starch materials.

  6. Hybrid fuzzy logic control of laser surface heat treatments

    International Nuclear Information System (INIS)

    Perez, Jose Antonio; Ocana, Jose Luis; Molpeceres, Carlos

    2007-01-01

    This paper presents an advanced hybrid fuzzy logic control system for laser surface heat treatments, which allows to increase significantly the uniformity and final quality of the obtained product, reducing the rejection rate and increasing the productivity and efficiency of the treatment. Basically, the proposed hybrid control structure combines a fuzzy logic controller, with a pure integral action, both fully decoupled, improving the performances of the process with a reasonable design cost, since the system nonlinearities are fully compensated by the fuzzy component of the controller, while the integral action contributes to eliminate the steady-state error

  7. Effect of pre-cooling and heat treatment on antioxidant enzymes ...

    African Journals Online (AJOL)

    Effect of pre-cooling and heat treatment on antioxidant enzymes profile of mango and banana. ... In banana, pre-cooling treatment (8 ºC) and heat treatment followed by cooling reduced CAT activity in peel and pulp, whereas POX activity increased. Pre-cooling and heat treatments altered normal homeostasis of these fruits, ...

  8. Magnetic enhancement and softening of fault gouges during seismic slip: Laboratory observation and implications

    Science.gov (United States)

    Yang, T.; Chen, J.; Dekkers, M. J.

    2017-12-01

    Anomalous rock magnetic properties have been reported in slip zones of many previous earthquakes (e.g., the 1995 Kobe earthquake, Japan; the 1999 Chi-Chi earthquake, Taiwan, and the 2008 Wenchuan earthquake, China). However, it is unclear whether short-duration frictional heating can actually induce such rock magnetic anomalies in fault zones; identification of this process in natural fault zones is not that straightforward. A promising approach to solve this problem is to conduct high-velocity friction (HVF) experiments that reproduce seismic fault movements and frictional heating in a simulated fault zone. Afterwards natural fault zones can be analyzed with renewed insight. Our HVF experiments on fault gouges that are simulating large amounts of earthquake slip, show significant magnetic enhancement and softening of sheared gouges. Mineral magnetic measurements reveal that magnetite was formed due to thermal decomposition of smectite during the HVF experiment on the paramagnetic fault gouge. Also, goethite was transformed to intermediate magnetite during the HVF experiment on the goethite-bearing fault gouge. Magnetic susceptibility, saturation remanence and saturation magnetization of sheared samples are linearly increasing with and strongly depend on the temperature rise induced by frictional heating; in contrast, coecivities are decreasing with increasing temperature. Thus, frictional heating can induce thermal decomposition/transformation during short-duration, high-velocity seismic slip, leading to magnetic enhancement and softening of a slip zone. Mineral magnetic methods are suited for diagnosing earthquake slip and estimating the temperature rise of co-seismic frictional heating.

  9. Water Softeners: How Much Sodium Do They Add?

    Science.gov (United States)

    ... diet is by putting away the saltshaker and cutting back on processed foods. With Sheldon G. Sheps, ... Original article: http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/water-softeners-sodium/ ...

  10. Effect of softening function on the cohesive crack fracture ...

    Indian Academy of Sciences (India)

    The cohesive crack model with linear softening yields the fracture process zones lower by ..... ignored during numerical simulation. In the crack band ..... performed with developed computer program using MATLAB for the following numerical.

  11. Evaluation of carbon diffusion in heat treatment of H13 tool steel under different atmospheric conditions

    Directory of Open Access Journals (Sweden)

    Maziar Ramezani

    2015-04-01

    Full Text Available Although the cost of the heat treatment process is only a minor portion of the total production cost, it is arguably the most important and crucial stage on the determination of material quality. In the study of the carbon diffusion in H13 steel during austenitization, a series of heat treatment experiments had been conducted under different atmospheric conditions and length of treatment. Four austenitization atmospheric conditions were studied, i.e., heat treatment without atmospheric control, heat treatment with stainless steel foil wrapping, pack carburization heat treatment and vacuum heat treatment. The results showed that stainless steel foil wrapping could restrict decarburization process, resulting in a constant hardness profile as vacuum heat treatment does. However, the tempering characteristic between these two heat treatment methods is different. Results from the gas nitrided samples showed that the thickness and the hardness of the nitrided layer is independent of the carbon content in H13 steel.

  12. Technical project of complex fast cycle heat treatment of hydrogenous coal preparation

    OpenAIRE

    Moiseev, V. A.; Andrienko, V. G.; Pileckij, V. G.; Urvancev, A. I.; Gvozdyakov, Dmitry Vasilievich; Gubin, Vladimir Evgenievich; Matveev, Aleksandr Sergeevich; Savostiyanova, Ludmila Viktorovna

    2015-01-01

    Problems of heat-treated milled hydrogenous coal preparation site creation in leading fast cycle heat treatment complex were considered. Conditions for effective use of electrostatic methods of heat-treated milled hydrogenous coal preparation were set. Technical project of heat treatment of milled hydrogenous coal preparation site was developed including coupling of working equipment complex on fast heat treatment and experimental samples of equipment being designed for manufacturing. It was ...

  13. Evaluation of the impact of lime softening waste disposal in ...

    Science.gov (United States)

    Drinking water treatment residues (WTR), generated from the lime softening processes, are commonly reused or disposed of in a number of applications; these include use as a soil amendment or a subsurface fill. Recently questions were posed by the Florida regulatory community on whether lime WTR that contained a small percentage of other treatment additives could appropriately be characterized as lime WTR, in terms of its total element content and leachability. A study was done using a broad range of leaching tests, including a framework of tests recently adopted by the United States-Environmental Protection Agency (EPA) and tests that were modified to account for scenario specific conditions, such as the presence of natural organic matter (NOM). The results of these additional leaching tests demonstrated that certain applications, including disposal in a water body with NOM or in placement anaerobic environment, did result in increased leaching of elements such as Fe, and that a site specific assessment should be conducted prior to using WTR in these types of applications. This study illustrates the importance of leaching test selection when attempting to provide an estimation of release in practice. Although leaching tests are just one component in a beneficial use assessment and other factors including aquifer and soil properties play a significant role in the outcome, leaching tests should be tailored to most appropriately represent the scenario or reuse ap

  14. Viscosity and Softening Behavior of Alkali Zinc Sulfophosphate Glasses

    DEFF Research Database (Denmark)

    Da, Ning; Krolikowski, Sebastian; Nielsen, Karsten Hansgaard

    2010-01-01

    We report on the softening properties and viscosity of glasses from the system ZnO-Na2O-SO3-P2O5 for low-temperature sealing applications. Up to a ratio of network-forming ions PO(4)3-:SO(4)2- of about 2:1, a gradual substitution of P2O5 by SO3 results in decreasing glass transition and softening...

  15. Genetic improvement of tomato by targeted control of fruit softening

    KAUST Repository

    Uluisik, Selman

    2016-07-25

    Controlling the rate of softening to extend shelf life was a key target for researchers engineering genetically modified (GM) tomatoes in the 1990s, but only modest improvements were achieved. Hybrids grown nowadays contain \\'non-ripening mutations\\' that slow ripening and improve shelf life, but adversely affect flavor and color. We report substantial, targeted control of tomato softening, without affecting other aspects of ripening, by silencing a gene encoding a pectate lyase. © 2016 Nature America, Inc. All rights reserved.

  16. Genetic improvement of tomato by targeted control of fruit softening

    KAUST Repository

    Uluisik, Selman; Chapman, Natalie H; Smith, Rebecca; Poole, Mervin; Adams, Gary; Gillis, Richard B; Besong, Tabot M.D.; Sheldon, Judith; Stiegelmeyer, Suzy; Perez, Laura; Samsulrizal, Nurul; Wang, Duoduo; Fisk, Ian D; Yang, Ni; Baxter, Charles; Rickett, Daniel; Fray, Rupert; Blanco-Ulate, Barbara; Powell, Ann L T; Harding, Stephen E; Craigon, Jim; Rose, Jocelyn K C; Fich, Eric A; Sun, Li; Domozych, David S; Fraser, Paul D; Tucker, Gregory A; Grierson, Don; Seymour, Graham B

    2016-01-01

    Controlling the rate of softening to extend shelf life was a key target for researchers engineering genetically modified (GM) tomatoes in the 1990s, but only modest improvements were achieved. Hybrids grown nowadays contain 'non-ripening mutations' that slow ripening and improve shelf life, but adversely affect flavor and color. We report substantial, targeted control of tomato softening, without affecting other aspects of ripening, by silencing a gene encoding a pectate lyase. © 2016 Nature America, Inc. All rights reserved.

  17. Brine reuse in ion-exchange softening: salt discharge, hardness leakage, and capacity tradeoffs.

    Science.gov (United States)

    Flodman, Hunter R; Dvorak, Bruce I

    2012-06-01

    Ion-exchange water softening results in the discharge of excess sodium chloride to the aquatic environment during the regeneration cycle. In order to reduce sodium chloride use and subsequent discharge from ion-exchange processes, either brine reclaim operations can be implemented or salt application during regeneration can be reduced. Both result in tradeoffs related to loss of bed volumes treated per cycle and increased hardness leakage. An experimentally validated model was used to compare concurrent water softening operations at various salt application quantities with and without the direct reuse of waste brine for treated tap water of typical midwestern water quality. Both approaches were able to reduce salt use and subsequent discharge. Reducing salt use and discharge by lowering the salt application rate during regeneration consequently increased hardness leakage and decreased treatment capacity. Single or two tank brine recycling systems are capable of reducing salt use and discharge without increasing hardness leakage, although treatment capacity is reduced.

  18. Effect of heat treatment on antimycotic activity of Sahara honey

    Directory of Open Access Journals (Sweden)

    Moussa Ahmed

    2014-11-01

    Full Text Available Objective: To evaluate the influence of the temperature on honey colour, polyphenol contents and antimycotic capacity and to evaluate the correlation between these parameters. Methods: Sahara honey were heated up to 25, 50, 75 and 100 °C for 15, 30 and 60 min, and their colour intensity, polyphenol contents and antimycotic capacity. The Folin-Ciocalteu test was used to determine the total polyphenol contents (TPC. The antimycotic activity was evaluated both by agar diffusion method and micro wells dilution method against the Candida albicans (C. albicans and Candida glabrata (C. glabrata. Results: Initial values for TPC in Sahara honey ranged from 0.55 to 1.14 mg of gallic acid per kg of honey, with the average value of 0.78 mg of gallic acid per kg of honey. The TPC values after heat-treatment were 0.54 to 1.54 with the average value of 1.49 mg. The minimal inhibitory concentrations before heat-treatment of Sahara honey against C. albicans and C. glabrata ranged from 3.06%-12.5% and 50% respectively. After heat-treatment the minimal inhibitory concentrations between 12.5% and 50% for C. albicans and C. glabrata, respectively. The diameters of inhibition zones of Sahara honey with 50% concentration varied from (12.67-15.00 mm by C. albicans to (14.33-15.67 mm by C. glabrata. The diameters of inhibition zones after heat-treatment at 25 and 50 °C for 15.30 and 60 min ranged from (2.00-18.67 mm by C. albicans to (8.00-16.67 mm by C. glabrata. Statistically significant relations between the TPC and the colour intensity of Sahara honey (r=0.99, P<0.05. Furthermore, the results showed that the TPC and colour is not correlated with the antimycotic capacity. Conclusions: To our knowledge this is the first report on the antimycotic capacity of Sahara honey.

  19. Modeling heat and mass transfer in the heat treatment step of yerba maté processing

    Directory of Open Access Journals (Sweden)

    J. M. Peralta

    2007-03-01

    Full Text Available The aim of this research was to estimate the leaf and twig temperature and moisture content of yerba maté branches (Ilex paraguariensis Saint Hilaire during heat treatment, carried out in a rotary kiln dryer. These variables had to be estimated (modeling the heat and mass transfer due to the difficulty of experimental measurement in the dryer. For modeling, the equipment was divided into two zones: the flame or heat treatment zone and the drying zone. The model developed fit well with the experimental data when water loss took place only in leaves. In the first zone, leaf temperature increased until it reached 135°C and then it slowly decreased to 88°C at the exit, despite the gas temperature, which varied in this zone from 460°C to 120°C. Twig temperature increased in the two zones from its inlet temperature (25°C up to 75°C. A model error of about 3% was estimated based on theoretical and experimental data on leaf moisture content.

  20. Applicability of Solid Solution Heat Treatments to Aluminum Foams

    Directory of Open Access Journals (Sweden)

    Miguel Rodríguez-Pérez

    2012-12-01

    Full Text Available Present research work evaluates the influence of both density and size on the treatability of Aluminum-based (6000 series foam-parts subjected to a typical solid solution heat treatment (water quenching. The results are compared with those obtained for the bulk alloy, evaluating the fulfilment of cooling requirements. Density of the foams was modeled by tomography analysis and the thermal properties calculated, based on validated density-scaled models. With this basis, cooling velocity maps during water quenching were predicted by finite element modeling (FEM in which boundary conditions were obtained by solving the inverse heat conduction problem. Simulations under such conditions have been validated experimentally. Obtained results address incomplete matrix hardening for foam-parts bigger than 70 mm in diameter with a density below 650 kg/m3. An excellent agreement has been found in between the predicted cooling maps and final measured microhardness profiles.

  1. Nanoscale thermal-mechanical probe determination of 'softening transitions' in thin polymer films

    International Nuclear Information System (INIS)

    Zhou Jing; Berry, Brian; Douglas, Jack F; Karim, Alamgir; Snyder, Chad R; Soles, Christopher

    2008-01-01

    We report a quantitative study of the softening behavior of glassy polystyrene (PS) films at length scales on the order of 100 nm using nano-thermomechanometry (nano-TM), an emerging scanning probe technique in which a highly doped silicon atomic force microscopy (AFM) tip is resistively heated on the surface of a polymer film. The apparent 'softening temperature' T s of the film is found to depend on the logarithm of the square root of the thermal ramping rate R. This relation allows us to estimate a quasi-equilibrium (or zero rate) softening transition temperature T s0 by extrapolation. We observe marked shifts of T s0 with decreasing film thickness, but the nature of these shifts, and even their sign, depend strongly on both the thermal and mechanical properties of the supporting substrate. Finite element simulations suggest that thin PS films on rigid substrates with large thermal conductivities lead to increasing T s0 with decreasing film thickness, whereas softer, less thermally conductive substrates promote reductions in T s0 . Experimental observations on a range of substrates confirm this behavior and indicate a complicated interplay between the thermal and mechanical properties of the thin PS film and the substrate. This study directly points to relevant factors for quantitative measurements of thermophysical properties of materials at the nanoscale using this nano-TM based method.

  2. Investigation of heat distribution during magnetic heating treatment using a polyurethane–ferrofluid phantom-model

    International Nuclear Information System (INIS)

    Henrich, F.; Rahn, H.; Odenbach, S.

    2014-01-01

    Magnetic heating treatment can be used as an adjuvant treatment for cancer therapy. In this therapy, magnetic nanoparticles are enriched inside the tumour and exposed to an alternating magnetic field. Due to magnetic losses the temperature in the tumour rises. The resulting temperature profile inside the tumour is useful for the therapeutic success. In this context heat transfer between tissue with nanoparticles and tissue without nanoparticles is a highly important feature which is actually not understood in detail. In order to investigate this, a phantom has been created which can be used to measure the temperature profile around a region enriched with magnetic nanoparticles. This phantom is composed of a material, which has similar thermal conductivity as human tissue. A tempered water bath surrounds the phantom to establish a constant surrounding temperature simulating the heat sink provided by the human body in a real therapeutic application. It has been found that even at a low concentration of magnetic nanoparticles around 13 mg/ml, sufficient heating of the enriched region can be achieved. Moreover it has been observed that the temperature drops rapidly in the material surrounding the enriched region. Corresponding numerical investigations provide a basis for future recalculations of the temperature inside the tumour using temperature data obtained in the surrounding tissue. - Highlights: • The temperature profile by magnetic hyperthermia was examined. • A model was built to get a deeper understanding of the temperature profile. • The temperature profile of the model inside magnetic fields was measured. • Based on the model a simulation of the temperature profile was performed. • The simulated temperature profile agreed well with the measured profile

  3. Effects of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) wood

    Science.gov (United States)

    Xianjun Li; Zhiyong Cai; Qunying Mou; Yiqiang Wu; Yuan Liu

    2011-01-01

    In this study the effect of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) was investigated. Wood specimens were subjected to heat treatment at 160, 180, 200 and 220°C for 1, 2, 3 and 4h. The results show that heat treatment resulted in a darkened color, decreased moisture performance and increased dimensional stability of...

  4. Optimization of properties of parts in the heat treatment

    International Nuclear Information System (INIS)

    Shpis, Kh.I.

    1981-01-01

    Properties of parts of the improved steel depending considerably on the structure obtained after the tempering have been investigated. It is shown that in many cases properties of steel with the structure of the tempered lower bainite are no worse than the properties of steels with the structure of tempered martensite. At certain dimensions of parts and under certain conditions of cooling tempering degree is determined with calcination. Calcination of steel is evaluated by the dispersion bands of hardness obtained using the method of end quenching. Account of the calcination when steels are selected permits to optimize part properties during heat treatment [ru

  5. COMPUTERIZED HEAT-TREATMENT IN A ZIMBABWEAN FACTORY

    Directory of Open Access Journals (Sweden)

    M. Collier

    2012-01-01

    Full Text Available In the context of Zimbabwe's current economic problems, parts of the manufacturing industry are turning their attention to the possibility of utilising local design talent in upgrading their manufacturing plants. This paper describes a project undertaken by the National University of Science and Technology to convert the heat-treatment process in a major manufacturing plant from semi -manual to a computerized one. The system comprises microcontroller connection to the furnaces and sensors, and communicates with a central computer on which software for a windowed user-interface is hosted. Experimental results for the system are presented, and a strategy for other companies in the same predicament is proposed.

  6. Vanadium and heat treatments effect on elastic characteristics of niobium

    International Nuclear Information System (INIS)

    Vasil'eva, E.V.; Tret'yakov, V.I.; Prokoshkin, D.A.; Pustovalov, V.A.

    1975-01-01

    The effect of vanadium content and of heat treatment conditions on the elastic properties of niobium at temperatures of 20 to 800 deg C was studied. Nb-V alloys were produced by binary vacuum remelting. The Nb-V alloys have been then subjected to thermal treatment. The total degree of deformation amounts to about 95%. The specimens were tested with a view to determine their microhardness, specific electric resistance, elasticity limit and modulus of elasticity. The elastic limit of niobium rises when alloyed with vanadium. With the increase of vanadium content the elastic limit of the alloy becomes greater. Pre-crystallization annealing at 600 - 700 deg C considerably increases the elastic limit, which is explained by development of the thermally activated processes leading to a decrease of dislocation mobility and thereby to a strengthening of the alloy

  7. Hierarchical Cu precipitation in lamellated steel after multistage heat treatment

    Science.gov (United States)

    Liu, Qingdong; Gu, Jianfeng

    2017-09-01

    The hierarchical distribution of Cu-rich precipitates (CRPs) and related partitioning and segregation behaviours of solute atoms were investigated in a 1.54 Cu-3.51 Ni (wt.%) low-carbon high-strength low-alloy (HSLA) steel after multistage heat treatment by using the combination of electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and atom probe tomography (APT). Intercritical tempering at 725 °C of as-quenched lathlike martensitic structure leads to the coprecipitation of CRPs at the periphery of a carbide precipitate which is possibly in its paraequilibrium state due to distinct solute segregation at the interface. The alloyed carbide and CRPs provide constituent elements for each other and make the coprecipitation thermodynamically favourable. Meanwhile, austenite reversion occurs to form fresh secondary martensite (FSM) zone where is rich in Cu and pertinent Ni and Mn atoms, which gives rise to a different distributional morphology of CRPs with large size and high density. In addition, conventional tempering at 500 °C leads to the formation of nanoscale Cu-rich clusters in α-Fe matrix. As a consequence, three populations of CRPs are hierarchically formed around carbide precipitate, at FSM zone and in α-Fe matrix. The formation of different precipitated features can be turned by controlling diffusion pathways of related solute atoms and further to tailor mechanical properties via proper multistage heat treatments.

  8. Modernization and efficiency of heat treatment and heating up plants; Modernisierung und Effizienz von Thermoprozessanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Peter [LOI Thermprocess GmbH, Essen (Germany); Kuehn, Friedhelm [Ingenieurbuero fuer Waermebehandlung, Industrieoefen und Energieberatung, Muelheim (Germany)

    2010-10-15

    A goal of this contribution is to show, using examples of the thermal heat treatment industry and the thermal processing units used there (Beltype plants, routary hearth, walking hearth, walking beam, pusher type furnaces and gas carburizing plants as well as case hardening plants), which increases in efficiency within and outside of the actual thermal treatment process and the necessary thermal processing units for the order are available today. From the possibilities of the reduction of energy employment resulting from that, a high potential for the discharge of the environment can be derived. The economic effect concerning energy employment and saving possibilities will also be considered. Concluding, examples of case-hardening show which variants of a change of process present themselves partially in the future, in order to achieve substantial production increases and thus energy cost reductions. (orig.)

  9. Heart rate variability during exertional heat stress: effects of heat production and treatment.

    Science.gov (United States)

    Flouris, Andreas D; Bravi, Andrea; Wright-Beatty, Heather E; Green, Geoffrey; Seely, Andrew J; Kenny, Glen P

    2014-04-01

    We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs. natural recovery) and the effect of exercise intensities (i.e., low vs. high) for restoring heart rate variability (HRV) indices during recovery from exertional heat stress (EHS). Nine healthy adults (26 ± 3 years, 174.2 ± 3.8 cm, 74.6 ± 4.3 kg, 17.9 ± 2.8 % body fat, 57 ± 2 mL·kg·(-1) min(-1) peak oxygen uptake) completed four EHS sessions incorporating either walking (4.0-4.5 km·h(-1), 2 % incline) or jogging (~7.0 km·h(-1), 2 % incline) on a treadmill in a hot-dry environment (40 °C, 20-30 % relative humidity) while wearing a non-permeable rain poncho for a slow or fast rate of rectal temperature (T re) increase, respectively. Upon reaching a T re of 39.5 °C, participants recovered until T re returned to 38 °C either passively or with whole-body immersion in 2 °C water. A comprehensive panel of 93 HRV measures were computed from the time, frequency, time-frequency, scale-invariant, entropy and non-linear domains. Exertional heat stress significantly affected 60/93 HRV measures analysed. Analyses during recovery demonstrated that there were no significant differences between HRV measures that had been influenced by EHS at the end of passive recovery vs. whole-body cooling treatment (p > 0.05). Nevertheless, the cooling treatment required statistically significantly less time to reduce T re (p whole-body immersion in 2 °C water results in faster cooling, there were no observed differences in restoration of autonomic heart rate modulation as measured by HRV indices with whole-body cold-water immersion compared to passive recovery in thermoneutral conditions.

  10. Heat treatment control of Bi-2212 coils: I. Unravelling the complex dependence of the critical current density of Bi-2212 wires on heat treatment

    Science.gov (United States)

    Shen, Tengming; Li, Pei; Ye, Liyang

    2018-01-01

    A robust and reliable heat treatment is crucial for developing superconducting magnets from several superconductors especially Bi-2212. An improper heat treatment may significantly reduce the critical current density Jc of a Bi-2212 superconducting coil, even to zero, since the Jc of Bi-2212 wires is sensitive to parameters of its heat treatment (partial melt processing). To provide an essential database for heat treating Bi-2212 coils, the dependence of Jc on heat treatment is studied systematically in 11 industrial Bi-2212 wires, revealing several common traits shared between these wires and outlier behaviors. The dependence of the Jc of Bi-2212 on heat treatment is rather complex, with many processing parameters affecting Jc, including the peak processing temperature Tp, the time at the peak temperature tp, the time in the melt tmelt, the rate at which Bi-2212 melt is initially cooled CR1, the rate at which the solidification of Bi-2212 melt occurs CR2, and the temperature Tq at which the cooling rate switches from CR1 to CR2. The role of these parameters is analyzed and clarified, in the perspective of heat treating a coil. Practical advices on heat treatment design are given. The ability of a Bi-2212 coil to follow the prescribed recipe decreases with increasing coil sizes. The size of a coil that can be properly heat treated is determined.

  11. Flexible and stable heat energy recovery from municipal wastewater treatment plants using a fixed-inverter hybrid heat pump system

    International Nuclear Information System (INIS)

    Chae, Kyu-Jung; Ren, Xianghao

    2016-01-01

    Highlights: • Specially designed fixed-inverter hybrid heat pump system was developed. • Hybrid operation performed better at part loads than single inverter operation. • The applied heat pump can work stably over a wide range of heat load variations. • Heat energy potential of treated effluent was better than influent. • The heat pump’s COP from the field test was 4.06 for heating and 3.64 for cooling. - Abstract: Among many options to improve energy self-sufficiency in sewage treatment plants, heat extraction using a heat pump holds great promise, since wastewater contains considerable amounts of thermal energy. The actual heat energy demand at municipal wastewater treatment plants (WWTPs) varies widely with time; however, the heat pumps typically installed in WWTPs are of the on/off controlled fixed-speed type, thus mostly run intermittently at severe part-load conditions with poor efficiency. To solve this mismatch, a specially designed, fixed-inverter hybrid heat pump system incorporating a fixed-speed compressor and an inverter-driven, variable-speed compressor was developed and tested in a real WWTP. In this hybrid configuration, to improve load response and energy efficiency, the base-heat load was covered by the fixed-speed compressor consuming relatively less energy than the variable-speed type at nominal power, and the remaining varying load was handled by the inverter compressor which exhibits a high load-match function while consuming relatively greater energy. The heat pump system developed reliably extracted heat from the treated effluent as a heat source for heating and cooling purposes throughout the year, and actively responded to the load changes with a high measured coefficient of performance (COP) of 4.06 for heating and 3.64 for cooling. Moreover, this hybrid operation yielded a performance up to 15.04% better on part loads than the single inverter operation, suggesting its effectiveness for improving annual energy saving when

  12. Twenty years of experience with central softening in The Netherlands : Water quality – Environmental benefits – Costs

    NARCIS (Netherlands)

    Hofman, J.A.M.H.; Kramer, O.J.I.; van der Hoek, J.P.; Nederlof, M; Groenendijk, M

    2006-01-01

    Central softening has been utilized by the Dutch water utilities since the late 1970s. It was introduced in the water treatment process as a method to supply water with an optimum water composition to prevent lead and copper release and to prevent excessive scaling. Twenty years of experience show

  13. Gas injection to inhibit migration during an in situ heat treatment process

    Science.gov (United States)

    Kuhlman, Myron Ira; Vinegar; Harold J.; Baker, Ralph Sterman; Heron, Goren

    2010-11-30

    Methods of treating a subsurface formation are described herein. Methods for treating a subsurface treatment area in a formation may include introducing a fluid into the formation from a plurality of wells offset from a treatment area of an in situ heat treatment process to inhibit outward migration of formation fluid from the in situ heat treatment process.

  14. Evaluation of carbon diffusion in heat treatment of H13 tool steel under different atmospheric conditions

    OpenAIRE

    Ramezani, Maziar; Pasang, Timotius; Chen, Zhan; Neitzert, Thomas; Au, Dominique

    2015-01-01

    Although the cost of the heat treatment process is only a minor portion of the total production cost, it is arguably the most important and crucial stage on the determination of material quality. In the study of the carbon diffusion in H13 steel during austenitization, a series of heat treatment experiments had been conducted under different atmospheric conditions and length of treatment. Four austenitization atmospheric conditions were studied, i.e., heat treatment without atmospheric contro...

  15. Influence of heat treatment on corrosive resistance of concrete steels

    International Nuclear Information System (INIS)

    Woldan, A.; Suliga, I.; Kusinski, J.; Jazowy, R.

    1998-01-01

    The reinforcing bars are essential elements of ferro-concrete structures. During the building structure service the reinforcing bars should co-operate with surrounding concrete. Any bonding defects as well as corrosion induced strength reduction may result in construction failure. The reinforcing steel working environment is determined by concrete chemical and phase composition and surrounding environmental properties. The aggressive corrosive activity of the letter implies necessity of effective ways development to protect elements against corrosion. The effect of heat treatment, increased Si content in steel on corrosion resistance of reinforcing steel in concrete was studied in the current work. Corrosion tests and metallographic examinations proved a positive influence of hardening and Si enrichment on corrosion resistance of reinforcing bars in ferro-concrete structures. (author)

  16. Zr-2.5 Nb microstructure evolution during heat treatments

    International Nuclear Information System (INIS)

    Campitelli, Emiliano N.; Banchik, Abrahan D.; Versaci, Raul A.

    1999-01-01

    This work has the following two basic objectives: 1) To gain experience in the preparation of thin layers of zirconium alloys to be used as T.E.M specimens. To construct a double jet thinning prototype able to perform this task with appropriate finishing and reproducible results to be used in a future work (point 2). To become familiar with the relevant parameters of the thinning process and to apply this experience in the prototype. The layers must have sufficient area with good transmission and mechanical support, free of deformations and defects polishing. 2) To perform T.E.M. observations and metallographies to study the microstructural evolution during heat treatments of Zr-2.5 Nb alloy samples. These samples were obtained from a pressure tube similar to those used in Candu power plants, in the as-received condition. This alloy served, in this application, to replace Zircaloy-2, for better creep and corrosion resistance. (author)

  17. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots.

    Science.gov (United States)

    Kok, H Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D; Stalpers, Lukas J A; Crezee, Johannes

    2017-11-15

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to improve the heating quality. The aim of this study was to evaluate the clinical benefit of online treatment planning during treatment of pelvic tumors heated with the AMC-8 locoregional hyperthermia system. For online adaptive hyperthermia treatment planning, a graphical user interface was developed. Electric fields were calculated in a preprocessing step using our in-house-developed finite-difference-based treatment planning system. This allows instant calculation of the temperature distribution for user-selected phase-amplitude settings during treatment and projection onto the patient's computed tomographic scan for online visualization. Online treatment planning was used for 14 treatment sessions in 8 patients to reduce the patients' reports of hot spots while maintaining the same level of tumor heating. The predicted decrease in hot spot temperature should be at least 0.5°C, and the tumor temperature should decrease less than 0.2°C. These predictions were compared with clinical data: patient feedback about the hot spot and temperature measurements in the tumor region. In total, 17 hot spot reports occurred during the 14 sessions, and the alternative settings predicted the hot spot temperature to decrease by at least 0.5°C, which was confirmed by the disappearance of all 17 hot spot reports. At the same time, the average tumor temperature was predicted to change on average -0.01°C (range, -0.19°C to 0.34°C). The measured tumor temperature change was on average only -0.02°C (range, -0.26°C to 0.31°C). In only 2 cases the temperature decrease was slightly larger than 0.2°C, but at most it was 0.26°C. Online application of hyperthermia treatment planning is

  18. Effect of heat treatment of whole cottonseed on in vitro, in situ and in ...

    African Journals Online (AJOL)

    Keywords: Amino acid flow, heat treatment, protein degradation, whole cononseed. * Author to whom ... heat-treated soybearu were compared with raw soybeans, it was found that ... et al., 1985; Faldet & Sarter, 1989) while milk fat percenrage.

  19. Structural steels for power generating equipment and heat and chemical heat treatments

    International Nuclear Information System (INIS)

    Astaf'ev, A.A.

    1979-01-01

    Development of structural steels for power generating equipment and for reactor engineering, in particular, is elucidated. Noted is utilization of the 15Kh2NMFA steels for the WWER-1000 reactor vessels, the 10GN2MFA steels for steam generators, pressurizers, vessels of the automatic emergency shut down and safety system; the 00Kh12N3DL steel for cast pump vessels and main locking bars. The recommendations on heat treatment of big forgings, for instance, ensuring the necessary complex of mechanical properties are given. Diffusion chromizing with subsequent nitriding of austenitic steels which increase durability of the components in BN reactors more than 4 times, is practised on a large scale

  20. Martensitic transformation and residual stresses after thermomechanical treatment of heat treatable steel 42CrMo4 (SAE 4140)

    Energy Technology Data Exchange (ETDEWEB)

    Weise, A. [Technische Univ. Chemnitz-Zwickau, Chemnitz (Germany). Fakultaet fuer Maschinenbau und Verfahrenstechnik; Fritsche, G. [Technische Univ. Chemnitz-Zwickau, Chemnitz (Germany). Fakultaet fuer Maschinenbau und Verfahrenstechnik

    1996-01-01

    The influence of thermomechanical deformation on the residual stresses caused by quenching in bar shaped specimens of heat treatable steel 42CrMo4 has been investigated using a mechanical method for determining the distribution of residual stresses of the first kind. The results obtained show that the residual stress distribution after quenching is affected by the strengthening and softening of the austenite as a result of deformation and recrystallization and the modified transformation behaviour in martensite stage. An attempt is made to discuss qualitatively the influence of these changes on the generation of residual stresses as compared to results obtained after conventional hardening. (orig.).

  1. Martensitic transformation and residual stresses after thermomechanical treatment of heat treatable steel 42CrMo4 (SAE 4140)

    International Nuclear Information System (INIS)

    Weise, A.; Fritsche, G.

    1996-01-01

    The influence of thermomechanical deformation on the residual stresses caused by quenching in bar shaped specimens of heat treatable steel 42CrMo4 has been investigated using a mechanical method for determining the distribution of residual stresses of the first kind. The results obtained show that the residual stress distribution after quenching is affected by the strengthening and softening of the austenite as a result of deformation and recrystallization and the modified transformation behaviour in martensite stage. An attempt is made to discuss qualitatively the influence of these changes on the generation of residual stresses as compared to results obtained after conventional hardening. (orig.)

  2. Saving energy resources during heat treatment - the most important problem of the branch

    Energy Technology Data Exchange (ETDEWEB)

    Zadernovskiy, V V; Firger, I V

    1980-01-01

    Natural gas fired thermal furnaces expend significantly less fuel than electric furnaces with an equal quality of metal heating. An important reserve in power reserve economy is the use of the forging heat in an article for heat treatment (TOB), where besides the power resources, metal is also saved as a result of the reduction in the volume of heating means and production spaces. From the experience in the progressive enterprises of the branch, in a number of cases it is possible to combine heating for plastic deformation with heating for primary or secondary heat treatment. Other measures are examined which save power resources in heat treatment: the use of thermal furnaces for aerodynamic heating, the use of local heat treatment, the reduction in the duration of the heat treatment processes, savings in the power carriers during heat treatment in furnaces with a roll out hearth. Fibrous refractory materials are being used more and more as fettling materials in the construction of thermal furnaces.

  3. Local total and radiative heat-transfer coefficients during the heat treatment of a workpiece in a fluidised bed

    International Nuclear Information System (INIS)

    Gao, W.M.; Kong, L.X.; Hodgson, P.D.

    2006-01-01

    The heat-transfer coefficients around a workpiece immersed in an electrically heated heat treatment fluidised bed were studied. A suspension probe designed to simulate a workpiece of complex geometry was developed to measure local total and radiative heat-transfer coefficients at a high bed temperature. The probe consisted of an energy-storage region separated by insulation from the fluidised bed, except for the measuring surface, and a multi-thermocouple measurement system. Experiments in the fluidised bed were performed for a fluidising medium of 120-mesh alumina, a wide temperature range of 110-1050 deg. C and a fluidising number range of 1.18-4.24. It was found that the workpiece surface temperature has a more significant effect on heat transfer than the bed temperature. The total heat-transfer coefficient at the upper surface of the workpiece sharply decreased at the start of heating, and then steadily increased as heating progressed, while a sharp decrease became a rapid increase and then a slow increase for the radiative heat-transfer coefficient. A great difference in the heat-transfer coefficients around the workpiece was observed

  4. Metadynamic and static recrystallization softening behavior of a bainite steel

    Science.gov (United States)

    Li, Lixin; Zheng, Liangyu; Ye, Ben; Tong, Zeqiong

    2018-01-01

    The metadynamic recrystallization (MDRX) and static recrystallization (SRX) softening behavior of a bainite steel was investigated by two-pass isothermal compression experiments at temperatures of 1173, 1273, 1373, and 1473 K and strain rates of 0.01, 0.1, 1, and 10 s-1 with inter-pass times of 1, 5, 10, and 30 s on a Gleeble-1500 thermo-mechanical simulator. Kinetic equations were developed to evaluate the softening fractions caused by MDRX and SRX. A comparison between the experimental and predicted softening fractions showed that the proposed kinetic equations can provide a precise estimation of the MDRX and SRX behavior of the studied steel. The results based on the kinetic equations indicated that the MDRX and SRX softening fraction increases with the increase in strain rate, deformation temperature, inter-pass time, and pre-strain; the activation energy of MDRX is much smaller than that of SRX; and the no-recrystallization temperature of the investigated steel is 1179.4 K.

  5. Hardening and softening mechanisms of pearlitic steel wire under torsion

    International Nuclear Information System (INIS)

    Zhao, Tian-Zhang; Zhang, Shi-Hong; Zhang, Guang-Liang; Song, Hong-Wu; Cheng, Ming

    2014-01-01

    Highlights: • Mechanical behavior of pearlitic steel wire is studied using torsion. • Work hardening results from refinement lamellar pearlitic structure. • Softening results from recovery, shear bands and lamellar fragmentations. • A microstructure based analytical flow stress model is established. - Abstract: The mechanical behaviors and microstructure evolution of pearlitic steel wires under monotonic shear deformation have been investigated by a torsion test and a number of electron microscopy techniques including scanning electron microscopy (SEM) and transmission electron microscopy (TEM), with an aim to reveal the softening and hardening mechanisms of a randomly oriented pearlitic structure during a monotonic stain path. Significantly different from the remarkable strain hardening in cold wire drawing, the strain hardening rate during torsion drops to zero quickly after a short hardening stage. The microstructure observations indicate that the inter-lamellar spacing (ILS) decreases and the dislocations accumulate with strain, which leads to hardening of the material. Meanwhile, when the strain is larger than 0.154, the enhancement of dynamic recovery, shear bands (SBs) and cementite fragmentations results in the softening and balances the strain hardening. A microstructure based analytical flow stress model with considering the influence of ILS on the mean free path of dislocations and the softening caused by SBs and cementite fragmentations, has been established and the predicted flow shear curve meets well with the measured curve in the torsion test

  6. Stress-Softening and Residual Strain Effects in Suture Materials

    Directory of Open Access Journals (Sweden)

    Alex Elías-Zúñiga

    2013-01-01

    Full Text Available This work focuses on the experimental characterization of suture material samples of MonoPlus, Monosyn, polyglycolic acid, polydioxanone 2–0, polydioxanone 4–0, poly(glycolide-co-epsilon-caprolactone, nylon, and polypropylene when subjected to cyclic loading and unloading conditions. It is found that all tested suture materials exhibit stress-softening and residual strain effects related to the microstructural material damage upon deformation from the natural, undistorted state of the virgin suture material. To predict experimental observations, a new constitutive material model that takes into account stress-softening and residual strain effects is developed. The basis of this model is the inclusion of a phenomenological nonmonotonous softening function that depends on the strain intensity between loading and unloading cycles. The theory is illustrated by modifying the non-Gaussian average-stretch, full-network model to capture stress-softening and residual strains by using pseudoelasticity concepts. It is shown that results obtained from theoretical simulations compare well with suture material experimental data.

  7. Methods for microwave heat treatment of manufactured components

    Science.gov (United States)

    Ripley, Edward B.

    2010-08-03

    An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases. The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

  8. Effects of Heat-treatments on the Mechanical Strength of Coated YSZ: An Experimental Assessment

    DEFF Research Database (Denmark)

    Toftegaard, Helmuth Langmaack; Sørensen, Bent F.; Linderoth, Søren

    2009-01-01

    The mechanical strength of thin, symmetric sandwich specimens consisting of a dense yttria-stabilized zirconia (YSZ) substrate coated with a porous NiO–YSZ layer at both major faces was investigated. Specimens were loaded in uniaxial tension to failure following heat treatments at various...... temperatures. In comparison with the YSZ material, the failure strength of coated specimens was found to increase for heat treatments at 1100°C, but decreased again with further increased heat-treatment temperatures....

  9. Characterization of major ripening events during softening in grape: turgor, sugar accumulation, abscisic acid metabolism, colour development, and their relationship with growth.

    Science.gov (United States)

    Castellarin, Simone D; Gambetta, Gregory A; Wada, Hiroshi; Krasnow, Mark N; Cramer, Grant R; Peterlunger, Enrico; Shackel, Kenneth A; Matthews, Mark A

    2016-02-01

    Along with sugar accumulation and colour development, softening is an important physiological change during the onset of ripening in fruits. In this work, we investigated the relationships among major events during softening in grape (Vitis vinifera L.) by quantifying elasticity in individual berries. In addition, we delayed softening and inhibited sugar accumulation using a mechanical growth-preventing treatment in order to identify processes that are sugar and/or growth dependent. Ripening processes commenced on various days after anthesis, but always at similarly low elasticity and turgor. Much of the softening occurred in the absence of other changes in berry physiology investigated here. Several genes encoding key cell wall-modifying enzymes were not up-regulated until softening was largely completed, suggesting softening may result primarily from decreases in turgor. Similarly, there was no decrease in solute potential, increase in sugar concentration, or colour development until elasticity and turgor were near minimum values, and these processes were inhibited when berry growth was prevented. Increases in abscisic acid occurred early during softening and in the absence of significant expression of the V. vinifera 9-cis-epoxycarotenoid dioxygenases. However, these increases were coincident with decreases in the abscisic acid catabolite diphasic acid, indicating that initial increases in abscisic acid may result from decreases in catabolism and/or exogenous import. These data suggest that softening, decreases in turgor, and increases in abscisic acid represent some of the earliest events during the onset of ripening. Later, physical growth, further increases in abscisic acid, and the accumulation of sugar are integral for colour development. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  10. Effect of heat-treatment on toughness and strength properties of C-Mn steel

    International Nuclear Information System (INIS)

    Mohd bin Harun; Goh Kian Seong; Jasmin binti Baba

    1991-01-01

    The strength and toughness of the heat-treated and tempered C-Mn are studied. Two types of heat-treatment have been carried out with the specimens in an argon gas. The variation in the fracture surfaces of the heat-treated and tempered specimens with impact test temperature is discussed also

  11. Effect of heat treatment of toughness and strength properties of C-Mn steel

    International Nuclear Information System (INIS)

    Mohamad bin Harun; Goh Kian Seong; Yasmin binti Baba

    1989-01-01

    The strength and toughness of the heat-treated and tempered C-Mn are studied. Two type of heat-treatments have been carried out with the specimens in an argon gas. The variation in the fracture surfaces of the heat-treated and tempered specimens with impact test temperatures also is discussed. (author)

  12. Calculation and Designing of Up-to-Date Gas-Flame Plants for Metal Heating and Heat Treatment

    Directory of Open Access Journals (Sweden)

    V. I. Тimoshpolsky

    2008-01-01

    Full Text Available An analysis of development trends in the CIS machine-building industry and current status of the heating and heat treatment furnaces of main machine-building enterprises of the Republic of Belarus as of the 1st quarter of 2008 is given in the paper.The paper presents the most efficient engineering solutions from technological and economic point of view that concern calculation and designing of up-to-date gas-flame plants which are to be applied for modernization of the current heating and heat treatment furnaces of the machine-building enterprises in the Republic of Belarus.A thermo-technical calculation of main indices of the up-to-date gas-flame plant has been carried out in the paper.

  13. Microstructural evolution of aluminide coatings on Eurofer during heat treatments

    International Nuclear Information System (INIS)

    Bhanumurthy, K.; Krauss, W.; Konys, J.

    2011-01-01

    Development of ceramic coatings are essential for the realization of Demo fusion reactor beyond ITER. These functional coatings have to be stable at high temperatures, provide insulating coatings to reduce MHD effects and also act as corrosion barriers to reduce tritium permeation. Some of important development of high temperature coatings are CVD process, powder slurry coatings, hot-dip aluminization and plasma detonation jet processes. Recently Galvono-Al (ECA) process is being used for depositing Al from organic electrolyte, where Al is existing as an toluol-based Al(C x H y ) complex. The deposit is performed under Ar cover gas at 100 deg C with a deposit rate of 10-12 μm/hr. This process is suitable for coating large and complex shaped assemblies and is a well established industrial process for coating Al for wide range of applications including automobile industry. In order to study the effect of high temperature on these coatings, few Al coated on Eurofer specimens were obtained from M/s. Rasant-Alcotec, Germany. The thickness of these coating is around 20 μm. The objective of the presents studies is to subject these coatings to standard heat treatment schedule of Eurofer and study the evolution of microchemistry and microstructure

  14. Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, Steven J [ORNL; Hsu, Julia [Massachusetts Institute of Technology (MIT)

    2010-11-01

    The cavitation-erosion resistance of carburized 316LN stainless steel was significantly degraded but not destroyed by heat treatment in the temperature range 500-800 C. The heat treatments caused rejection of some carbon from the carburized layer into an amorphous film that formed on each specimen surface. Further, the heat treatments encouraged carbide precipitation and reduced hardness within the carburized layer, but the overall change did not reduce surface hardness fully to the level of untreated material. Heat treatments as short as 10 min at 650 C substantially reduced cavitation-erosion resistance in mercury, while heat treatments at 500 and 800 C were found to be somewhat less detrimental. Overall, the results suggest that modest thermal excursions perhaps the result of a weld made at some distance to the carburized material or a brief stress relief treatment will not render the hardened layer completely ineffective but should be avoided to the greatest extent possible.

  15. Heat treatment device for extending the life of a pressure vessel, particularly a reactor pressure vessel

    International Nuclear Information System (INIS)

    Krauss, P.; Mueller, E.; Poerner, H.; Weber, R.

    1979-01-01

    A support body in the form of an insulating cylinder is tightly sealed by connected surfaces at its outer circumference to the inner wall of the pressure vessel. It forms an annular heating space. The heat treatment or tempering of the pressure vessel takes place with the reactor space empty and screened from the outside by ceiling bolts. Heating gas or an induction winding can be used as the means of heating. (DG) [de

  16. Effect of heat treatment on the microstructure and properties of Ni based soft magnetic alloy.

    Science.gov (United States)

    Li, Chunhong; Ruan, Hui; Chen, Dengming; Li, Kejian; Guo, Donglin; Shao, Bin

    2018-04-20

    A Ni-based alloy was heat treated by changing the temperature and ambient atmosphere of the heat treatment. Morphology, crystal structure, and physical performance of the Ni-based alloy were characterized via SEM, XRD, TEM, and PPMS. Results show that due to the heat treatment process, the grain growth of the Ni-based alloy and the removal of impurities and defects are promoted. Both the orientation and stress caused by rolling are reduced. The permeability and saturation magnetization of the alloy are improved. The hysteresis loss and coercivity are decreased. Higher heat treatment temperature leads to increased improvement of permeability and saturation magnetization. Heat treatment in hydrogen is more conducive to the removal of impurities. At the same temperature, the magnetic performance of the heat-treated alloy in hydrogen is better than that of an alloy with heat treatment in vacuum. The Ni-based alloy shows an excellent magnetic performance on 1,373 K heat treatment in hydrogen atmosphere. In this process, the µ m , B s , P u , and H c of the obtained alloy are 427 mHm -1 , 509 mT, 0.866 Jm -3 , and 0.514 Am -1 , respectively. At the same time, the resistivity of alloy decreases and its thermal conductivity increases in response to heat treatment. © 2018 Wiley Periodicals, Inc.

  17. Nuclear safety inspection in treatment process for SG heat exchange tubes deficiency of unit 1, TNPS

    International Nuclear Information System (INIS)

    Zhang Chunming; Song Chenxiu; Zhao Pengyu; Hou Wei

    2006-01-01

    This paper describes treatment process for SG heat exchange tubes deficiency of Unit 1, TNPS, nuclear safety inspection of Northern Regional Office during treatment process for deficiency and further inspection after deficiency had been treated. (authors)

  18. The local heat treatment equipment and technology of the pipelines welded joints

    International Nuclear Information System (INIS)

    Korol'kov, P.M.

    1998-01-01

    The principal methods and equipment for local treatment of the pipe-lines weld joints in different industry branches is described. Recommendations about heat treatment equipment and technology application are given

  19. Study of critical dependence of stable phases in Nitinol on heat treatment using electrical resistivity probe

    International Nuclear Information System (INIS)

    Uchil, J.; Mohanchandra, K.P.; Kumara, K.G.; Mahesh, K.K.

    1998-01-01

    Phase transformations in 40% cold-worked Nitinol as a function of heat treatment have been studied using electrical resistivity variation with temperature. The stabilisation of austenitic, rhombohedral and martensitic phases is shown to critically depend on the temperatures of heat treatment by the analysis of temperature dependence of electrical resistivity in heating and cooling parts of the cycle. Characteristic values of electrical resistivity of the stable phases are determined. The R-phase has been found to form continuously with increasing heat-treatment temperature starting from room temperature and to suddenly disappear beyond heat-treatment at 683 K. The observed presence or absence of R-phase is confirmed by heat capacity measurements as a function of temperature. (orig.)

  20. Prediction of heat treatment in food processing machinery

    DEFF Research Database (Denmark)

    Karlson, Torben; Friis, Alan; Szabo, Peter

    1997-01-01

    The velocity and temperature fields of a shear thinning fluid in a co-rotating disc scraped surface heat exchanger (CDHE) are calculated using the finite element method. By tracking and timingparticles through the heat exchanger residence time and thermal time distributions are computed. The resi...

  1. Solving the Standard Model Problems in Softened Gravity

    CERN Document Server

    Salvio, Alberto

    2016-11-16

    The Higgs naturalness problem is solved if the growth of Einstein's gravitational interaction is softened at an energy $ \\lesssim 10^{11}\\,$GeV (softened gravity). We work here within an explicit realization where the Einstein-Hilbert Lagrangian is extended to include terms quadratic in the curvature and a non-minimal coupling with the Higgs. We show that this solution is preserved by adding three right-handed neutrinos with masses below the electroweak scale, accounting for neutrino oscillations, dark matter and the baryon asymmetry. The smallness of the right-handed neutrino masses (compared to the Planck scale) and the QCD $\\theta$-term are also shown to be natural. We prove that a possible gravitational source of CP violation cannot spoil the model, thanks to the presence of right-handed neutrinos. Starobinsky inflation can occur in this context, even if we live in a metastable vacuum.

  2. Hardening by annealing and softening by deformation in nanostructured metals

    DEFF Research Database (Denmark)

    Huang, X.; Hansen, N.; Tsuji, N.

    2006-01-01

    We observe that a nanostructured metal can be hardened by annealing and softened when subsequently deformed, which is in contrast to the typical behavior of a metal. Microstructural investigation points to an effect of the structural scale on fundamental mechanisms of dislocation-dislocation and ......We observe that a nanostructured metal can be hardened by annealing and softened when subsequently deformed, which is in contrast to the typical behavior of a metal. Microstructural investigation points to an effect of the structural scale on fundamental mechanisms of dislocation....... As a consequence, the strength decreases and the ductility increases. These observations suggest that for materials such as the nanostructured aluminum studied here, deformation should be used as an optimizing procedure instead of annealing....

  3. Softening Behavior of a New Al-Zn-Mg-Cu Alloy Due to TIG Welding

    Science.gov (United States)

    Zhang, Liang; Li, Xiaoyan; Nie, Zuoren; Huang, Hui; Sun, Jiantong

    2016-05-01

    A new Al-Zn-Mg-Cu alloy with T6 temper was welded by TIG welding, and the softening behavior of the joint was evaluated. Results show that the ultimate tensile strength of the joint is 436.2 ± 26.4 MPa which is about 64.5% of that of the base metal (BM). Fusion zone (FZ) is the weakest region even though its microhardness increases from 107.6 to 131.3 HV within 90 days after welding. Microhardness of the heat-affected zone (HAZ) adjacent to FZ increases from 125.2 to 162.3 HV within 90 days. However, a valley value of microhardness appears in the rest of the HAZ that increases from 112.1 to 128.1 HV within 90 days. The variation of grain size and precipitates is regarded as the main cause of softening in both FZ and HAZ. The grain size of FZ is about 33.9 μm, whereas 8.7 and 8.4 μm for HAZ and BM, respectively. A large number of η' phases distribute dispersively in BM, whereas precipitates in FZ identified as GPI zones are finer and fewer. Besides, precipitates in HAZ adjacent to FZ are also GPI zones. Precipitates in HAZ far away from FZ are coarser and fewer than those in BM and η phases begin to emerge.

  4. A novel laboratory scale method for studying heat treatment of cake flour

    OpenAIRE

    Chesterton, AKS; Wilson, David Ian; Sadd, PI; Moggridge, Geoffrey Dillwyn

    2014-01-01

    A lab-scale method for replicating the time–temperature history experienced by cake flours undergoing heat treatment was developed based on a packed bed configuration. The performance of heat-treated flours was compared with untreated and commercially heat-treated flour by test baking a high ratio cake formulation. Both cake volume and AACC shape measures were optimal after 15 min treatment at 130 °C, though their values varied between harvests. Separate oscillatory rheometry tests of cake ba...

  5. Heat Treatment of Gas-Atomized Powders for Cold Spray Deposition

    Science.gov (United States)

    Story, William A.; Brewer, Luke N.

    2018-02-01

    This communication demonstrates the efficacy of heat treatment on the improved deposition characteristics of aluminum alloy powders. A novel furnace was constructed for solutionizing of feedstock powders in an inert atmosphere while avoiding sintering. This furnace design achieved sufficiently high cooling rates to limit re-precipitation during powder cooling. Microscopy showed homogenization of the powder particle microstructures after heat treatment. Cold spray deposition efficiency with heat-treated powders substantially increased for the alloys AA2024, AA6061, and AA7075.

  6. Heat stroke during long-term clozapine treatment: should we be concerned about hot weather?

    OpenAIRE

    Hoffmann, Maurício Scopel; Oliveira, Lucas Mendes; Lobato, Maria Inês Rodrigues; Belmonte-de-Abreu, Paulo

    2016-01-01

    Objective To describe the case of a patient with schizophrenia on clozapine treatment who had an episode of heat stroke. Case description During a heat wave in January and February 2014, a patient with schizophrenia who was on treatment with clozapine was initially referred for differential diagnose between systemic infection and neuroleptic malignant syndrome, but was finally diagnosed with heat stroke and treated with control of body temperature and hydration. Comments This report aims to...

  7. Effect of heat treatment duration on phase separation of sodium borosilicate glass, containing copper

    International Nuclear Information System (INIS)

    Shejnina, T.G.; Gutner, S.Kh.; Anan'in, N.I.

    1989-01-01

    The effect of heat treatment duration on phase separation of sodium borosilicate (SBS) glass, containing copper is studied. It is stated that phase separation close to equilibrium one is attained under 12 hours of heat treatment of SBS glass containing copper

  8. Industrial heat treatment of R-HPDC A356 automotive brake callipers

    CSIR Research Space (South Africa)

    Chauke, L

    2012-10-01

    Full Text Available Heat treatment of rheo-high pressure die cast (R-HPDC) A356 brake callipers has produced good mechanical properties on the laboratory scale. An industrial heat treatment is required to evaluate the applicability and conformance of the R-HPDC A356...

  9. Relaxation of residual stress in MMC after combined plastic deformation and heat treatment

    International Nuclear Information System (INIS)

    Bruno, G.; Ceretti, M.; Girardin, E.; Giuliani, A.; Manescu, A.

    2004-01-01

    Neutron Diffraction shows that plastic pre-deformation and heat treatments have opposite effects on the residual stress in Al-SiC p composites. The thermal micro residual stress is relaxed or even reversed by pre-strains above 0.2%, but restored by heat treatments. The sense of relaxation changes above 400 deg. C (the mixing temperature)

  10. Influence of heat treatment on magnesium alloys meant to automotive industry

    NARCIS (Netherlands)

    Popescu, G.; Moldovan, P.; Bojin, D.; Sillekens, W.H.

    2009-01-01

    The paper presents a study concerning the heat treatment realized on magnesium alloys, from AZ80 and ZK60 class. These alloys are destined to replace the conventional ferrous and aluminum alloys in automotive industry. It was realized the heat treatment, T5 - artificially aging, and it were

  11. Pemanfaatan ter sebagai softener dalam pembuatan karet riklim

    Directory of Open Access Journals (Sweden)

    Arum Yuniari

    2006-07-01

    Full Text Available The aims of this research was to study the effect of Coal Tar as softener for reclaim rubber production from waste of rubber of tyre rethreading as input materials was scrap rubber. Coal Tar as softener was used with variation; 2,5; 5; 7,5; 10; 12,5 and 15% respectively from total scrap rubber. Reclaimed rubber was made at temperature 1200C for 1 hour in autoclave and than it was subsequently ground with two rolls mills. The characteristics of the reclaimed rubber was tested for the vulcanization and physical properties. The results showed that Coal Tar could be utilized as softener for reclaimed rubber. Reclaimed rubber production containing Coal Tar 15% would give good vulcanization and physical properties. The vulcanization 1062 seconds, maximum torque 39,08 kgf-cm, minimum torque 4,71 kgf-cm. Good physical properties : tensile strength 80,74 kg/cm2 elongation at break 444,62%, hardness 49 shore A, tear strength 40,39 kg/cm, density 1,15 g/cm3, abrasion resistance 1,87 mm3/kgm, and no crack detected on the flex cracking test of 150 kcs

  12. Effects of heat treatment on the mechanical properties of kenaf fiber

    Energy Technology Data Exchange (ETDEWEB)

    Carada, Paulo Teodoro D. L. [Master’s student in the Graduate School of Science and Engineering, Mechanical Engineering, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, Kyoto Prefecture, 610-0394 (Japan); Fujii, Toru; Okubo, Kazuya [Professor in the Faculty of Science and Engineering, Department of Mechanical and Systems Engineering, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, Kyoto Prefecture, 610-0394 (Japan)

    2016-05-18

    Natural fibers are utilized in various ways. One specific application of it, is in the field natural fiber composite (NFC). Considerable amount of researches are conducted in this field due to rising concerns in the harmful effects of synthetic materials to the environment. Additionally, these researches are done in order to overcome the drawbacks which limit the wide use of natural fiber. A way to improve NFC is to look into the reinforcing component (natural fiber). Treatments, which are classified as mechanical or chemical in nature, can be done in order to improve the performance of the natural fiber. The aim of this study is to assess the effects of heat treatment in the mechanical properties of kenaf fiber. In addition, the response of mechanical properties after exposure to high moisture environment of heat-treated kenaf fibers was observed. Heat treatment was done for one hour with the following heating temperatures: 140, 160, 180, and 200 °C. X-ray diffraction analysis was done to calculate the crystallinity index of kenaf fibers after heat treatment. The results showed that increase in tensile strength can be attained when kenaf fibers are heat treated at 140 °C. However, the tensile modulus showed inconsistency with respect to heat treatment temperature. The computed crystallinity index of the fiber matched the tensile strength observed in non-treated and heat-treated kenaf fibers. The results obtained in this study can be used for applications where heat treatment on kenaf fibers is needed.

  13. Study of heat treatment parameters for large-scale hydraulic steel gate track

    Directory of Open Access Journals (Sweden)

    Ping-zhou Cao

    2013-10-01

    Full Text Available In order to enhance external hardness and strength, a large-scale hydraulic gate track should go through heat treatment. The current design method of hydraulic gate wheels and tracks is based on Hertz contact linear elastic theory, and does not take into account the changes in mechanical properties of materials caused by heat treatment. In this study, the heat treatment parameters were designed and analyzed according to the bearing mechanisms of the wheel and track. The quenching process of the track was simulated by the ANSYS program, and the temperature variation, residual stress, and deformation were obtained and analyzed. The metallurgical structure field after heat treatment was predicted by the method based on time-temperature-transformation (TTT curves. The results show that the analysis method and designed track heat treatment process are feasible, and can provide a reference for practical projects.

  14. Heat treatment evaluation of steel ASTM A-131 grade A by X-Ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Junior, Francisco; Feio, Luciana Gaspar; Costa, Ednelson Silva; Rodrigues, Lino Alberto Soares; Braga, Eduardo Magalhaes, E-mail: juniorferrer93@gmail.com [Universidade Federal do Pará (UFPA), Belém, PA (Brazil)

    2016-07-01

    Full text: This study evaluates the residual stress of naval steel ASTM A-131 grade A before and after heat treatment. Residual stresses were determined by the technique of X-ray diffraction (XRD). Before heat treatment the residual stress measurements were made at 36 (thirty six) points distributed in a specimen with dimensions of 400 mm long, 200 mm wide and 95 mm thick, then the plate under analysis was brought to the oven for the implementation of heat treatment. To check the performance of the heat treatment, the plate was again subjected to XRD measurements of the same points previously measured in order to compare the residual stresses. As result, there was a reduction of residual stresses with the application of heat treatment. References: [1] COLPAERT, H. Metalografia dos Produtos Siderurgicos Comuns. 4 Edição. Editora Blucher. Saõ Paulo, SP, 2008. [2] HILL, R. Princípios de Metalurgia Física, 1992. (author)

  15. Dimensional Behavior of Matrix Graphite Compacts during Heat Treatments for HTGR Fuel Element Fabrication

    International Nuclear Information System (INIS)

    Lee, Young-Woo; Yeo, Seunghwan; Cho, Moon Sung

    2015-01-01

    The carbonization is a process step where the binder that is incorporated during the matrix graphite powder preparation step is evaporated and the residue of the binder is carbonized during the heat treatment at about 1073 K. This carbonization step is followed by the final high temperature heat treatment where the carbonized compacts are heat treated at 2073-2173 K in vacuum for a relatively short time (about 2 hrs). In order to develop a fuel compact fabrication technology, and for fuel matrix graphite to meet the required material properties, it is essential to investigate the relationship among the process parameters of the matrix graphite powder preparation, the fabrication parameters of fuel element green compact and the heat treatments conditions, which has a strong influence on the further steps and the material properties of fuel element. In this work, the dimensional changes of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed, keeping other process parameters constant, such as the binder content, carbonization time, temperature and atmosphere (two hours ant 1073K and N2 atmosphere). In this work, the dimensional variations of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed

  16. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    GREGO

    2006-12-18

    Dec 18, 2006 ... enzymes in plant and its resistance to heat has been reported by a ... sintered glass funnel and washed with cold acetone under low vacuum ... Peroxidase activity was determined by measuring the colour deve- lopment at ...

  17. Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment

    OpenAIRE

    Baars, Destiny L.; Takle, Kendra A.; Heier, Jonathon; Pelegri, Francisco

    2016-01-01

    Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, specifically the generation of homozygous gynogenetic diploids is useful in genetic analysis because it allows the direct production of homozygotes from a single heterozygous mother. This article describes a modified protocol for ploidy duplication based on a heat pulse during the first cell cycle, Heat Shock 2 (HS2). Through inhibition of centriole...

  18. Interactions between goethite particles subjected to heat treatment

    DEFF Research Database (Denmark)

    Madsen, Daniel Esmarch; Hansen, Mikkel Fougt; Koch, C.B.

    2008-01-01

    We have studied the effect of heating on the magnetic properties of particles of nanocrystalline goethite by use of Mossbauer spectroscopy. Heating at 150 degrees C for 24 h leads to a change in the quadrupole shift in the low-temperature spectra, indicating a rotation of the sublattice...... magnetization directions. Fitting of quantiles, derived from the asymmetrically broadened spectra between 80 and 300 K, to the superferromagnetism model indicates that this change is due to a stronger magnetic coupling between the particles....

  19. Gas Furnace with Pulsed Feeding of the Heating Agent for Volume Precision Heat Treatment of CCM Rolls

    Science.gov (United States)

    Moroz, V. I.; Egorova, V. M.; Gusev, S. V.

    2001-05-01

    A standard chamber batch furnace of the Severstal' plant has been modified for precision heat treatment of CCM rolls. The certification tests of a charge of rolls from steel 24KhM1F have shown the technical and economical advantages of the new design.

  20. Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment.

    Science.gov (United States)

    Ramesh, Gopalan; Prabhu, Narayan Kotekar

    2011-04-14

    The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

  1. Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment

    Directory of Open Access Journals (Sweden)

    Ramesh Gopalan

    2011-01-01

    Full Text Available Abstract The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

  2. Phase-change materials: vibrational softening upon crystallization and its impact on thermal properties

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, Toshiyuki [Materials Science and Analysis Technology Centre, Panasonic Corporation, Osaka (Japan); Japan Synchrotron Radiation Research Institute Hyogo (Japan); Yamada, Noboru [Digital and Network Technology Development Centre, Panasonic Corporation, Osaka (Japan); Japan Synchrotron Radiation Research Institute Hyogo (Japan); Kojima, Rie [Digital and Network Technology Development Centre, Panasonic Corporation, Osaka (Japan); Shamoto, Shinichi [Neutron Science Research Centre, Japan Atomic Energy Research Institute, Ibaraki (Japan); Sato, Masugu; Tanida, Hajime; Uruga, Tomoya; Kohara, Shinji [Japan Synchrotron Radiation Research Institute, Hyogo (Japan); Takata, Masaki [SPring-8/RIKEN, Hyogo, Japan, Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo, Chiba (Japan); Zalden, Peter; Bruns, Gunnar; Wuttig, Matthias [I. Physikalisches Institut und JARA-FIT, RWTH Aachen Univ. (Germany); Sergueev, Ilya [European Synchrotron Radiation Facility, Grenoble (France); Wille, Hans Christian [Deutsches Elektronen-Synchrotron, Hamburg (Germany); Hermann, Raphael Pierre [Juelich Centre for Neutron Science JCNS and Peter Gruenberg, Institut PGI, JARA-FIT, Forschungszentrum Juelich GmbH (Germany); Faculte des Sciences, Universite de Liege (Belgium)

    2011-06-21

    Crystallization of an amorphous solid is usually accompanied by a significant change of transport properties, such as an increase in thermal and electrical conductivity. This fact underlines the importance of crystalline order for the transport of charge and heat. Phase-change materials, however, reveal a remarkably low thermal conductivity in the crystalline state. The small change in this conductivity upon crystallization points to unique lattice properties. The present investigation reveals that the thermal properties of the amorphous and crystalline state of phase-change materials show remarkable differences such as higher thermal displacements and a more pronounced anharmonic behavior in the crystalline phase. These findings are related to the change of bonding upon crystallization, which leads to an increase of the sound velocity and a softening of the optical phonon modes at the same time. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Dynamical Treatment of Virialization Heating in Galaxy Formation

    Science.gov (United States)

    Wang, Peng; Abel, Tom

    2008-01-01

    In a hierarchical picture of galaxy formation virialization continually transforms gravitational potential energy into kinetic energies of the baryonic and dark matter. For the gaseous component the kinetic, turbulent energy is transformed eventually into internal thermal energy through shocks and viscous dissipation. Traditionally this virialization and shock heating has been assumed to occur instantaneously, allowing an estimate of the gas temperature to be derived from the virial temperature defined from the embedding dark matter halo velocity dispersion. As the mass grows the virial temperature of a halo grows. Mass accretion hence can be translated into a heating term. We derive this heating rate from the extended Press Schechter formalism and demonstrate its usefulness in semianalytical models of galaxy formation. Our method explicitly conserves energy, unlike the previous impulsive heating assumptions. Our formalism can trivially be applied in all current semianalytical models as the heating term can be computed directly from the underlying merger trees. Our analytic results for the first cooling halos and the transition from cold to hot accretion are in agreement with numerical simulations.

  4. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarishirazabad, Mehdi [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Azadi, Mohammad, E-mail: m_azadi@ip-co.com [Fatigue and Wear Workgroup, Irankhodro Powertrain Company (IPCO), Tehran (Iran, Islamic Republic of); Hossein Farrahi, Gholam [School of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Winter, Gerhard; Eichlseder, Wilfred [Chair of Mechanical Engineering, University of Leoben, Leoben (Austria)

    2013-12-20

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests.

  5. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    International Nuclear Information System (INIS)

    Mokhtarishirazabad, Mehdi; Azadi, Mohammad; Hossein Farrahi, Gholam; Winter, Gerhard; Eichlseder, Wilfred

    2013-01-01

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests

  6. Evaluation of dry heat treatment of soft wheat flour for the production of high ratio cakes.

    Science.gov (United States)

    Keppler, S; Bakalis, S; Leadley, C E; Sahi, S S; Fryer, P J

    2018-05-01

    An accurate method to heat treat flour samples has been used to quantify the effects of heat treatment on flour functionality. A variety of analytical methods has been used such as oscillatory rheology, rheomixer, solvent retention capacity tests, and Rapid Visco Analysis (RVA) in water and in aqueous solutions of sucrose, lactic acid, and sodium carbonate. This work supports the hypothesis that heat treatment facilitates the swelling of starch granules at elevated temperature. Results furthermore indicated improved swelling ability and increased interactions of flour polymers (in particular arabinoxylans) of heat treated flour at ambient conditions. The significant denaturation of the proteins was indicated by a lack of gluten network formation after severe heat treatments as shown by rheomixer traces. Results of these analyses were used to develop a possible cake flour specification. A method was developed using response surfaces of heat treated flour samples in the RVA using i) water and ii) 50% sucrose solution. This can uniquely characterise the heat treatment a flour sample has received and to establish a cake flour specification. This approach might be useful for the characterisation of processed samples, rather than by baking cakes. Hence, it may no longer be needed to bake a cake after flour heat treatment to assess the suitability of the flour for high ratio cake production, but 2 types of RVA tests suffice. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Effect of heat treatment upon the fatigue-crack growth behavior of Alloy 718 weldments

    International Nuclear Information System (INIS)

    James, L.A.; Mills, W.J.

    1981-05-01

    Gas-tungsten-arc weldments in Alloy 718 were studied in fatigue-crack growth test conducted at five temperatures over the range 24--649 degree C. In general, crack growth rates increased with increasing temperature, and weldments given the ''conventional'' post-weld heat-treatment generally exhibited crack growth rates that were higher than for weldments given the ''modified'' (INEL) heat-treatment. Limited testing in the as-welded condition revealed crack growth rates significantly lower than observed for the heat-treated cases, and this was attributed to residual stresses. Three different heats of filler wire were utilized, and no heat-to-heat variations were noted. 23 refs., 9 figs., 6 tabs

  8. Optimisation of the T6 heat treatment of rheocast alloy A356

    CSIR Research Space (South Africa)

    Moller, H

    2007-11-01

    Full Text Available popular solution heat treatment employed for SSM processed A356 is 6 hours at 540oC (i.e. similar to that used for permanent mould cast A356)6,7,9. Only limited work has been performed on the optimisation of the solution heat treatment of SSM processed... was not adequately studied by either Dewhirst8 or Rosso and Actis Grande5. The optimum artificial aging heat treatment proposed in both papers5,8 is 180oC for 4 hours. This was also confirmed in this work, but importantly, this applies only when natural aging...

  9. EFFECT OF HEAT TREATMENT ON THE SURVIVAL OF ...

    African Journals Online (AJOL)

    BARTH EKWUEME

    seconds at temperatures ranging from 69OC to 73OC. E. coli O157:H7 ... inoculum was added to 90ml of sterile raw milk (heated in water bath ..... the high temperature short time (HTST) pasteurization technique .... I. The use of selective media.

  10. Influence of heat treatment on microstructure and passivity of Cu ...

    Indian Academy of Sciences (India)

    200 ◦C for 20 h in salt bath and air cooled), B (heating up to 800 ◦C for 20 h and water ... chloride ions on passivity was associated with the formation of copper oxides/hydroxide and ... passive layer inhibits copper redeposition and/or preferen-.

  11. Development of Tensile Softening Model for Plain Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.K.; Song, Y.C. [Korea Electric Power Research Institute, Taejon (Korea)

    2002-07-01

    Large-scale direct tensile softenng tests using plate concrete specimens(4000, 5000psi) with notch were performed under uniaxial stress. There were presented the basic physical properties and the complete load-CMOD(Crack Mouth Opening Displacement) curves for them And them the fracture energy was evaluated using the complete load-CMOD curves respectively, and there was presents optimal tensile softening model which is modified by a little revision of an existing one. Therefore, here provided the real verification data through the tests for developing other nonlinear concrete finite element models. (author). 32 refs., 38 figs., 4 tabs.

  12. Softening the supersymmetric flavor problem in orbifold grand unified theories

    International Nuclear Information System (INIS)

    Kajiyama, Yuji; Terao, Haruhiko; Kubo, Jisuke

    2004-01-01

    The infrared attractive force of the bulk gauge interactions is applied to soften the supersymmetric flavor problem in the orbifold SU(5) grand unified theory of Kawamura. Then this force aligns in the infrared regime the soft supersymmetry breaking terms out of their anarchical disorder at a fundamental scale, in such a way that flavor-changing neutral currents as well as dangerous CP-violating phases are suppressed at low energies. It is found that this dynamical alignment is sufficiently good compared with the current experimental bounds, as long as the diagonalization matrices of the Yukawa couplings are CKM-like

  13. Heat treatment regularity for viscose products in plate scrapers heat exchanger

    Directory of Open Access Journals (Sweden)

    K. A. Rashkin

    2012-01-01

    Full Text Available The current work describesthe construction of scraperplate-typeheat exchangerscurrently usedin industryand thetraffic patternof the productin it. Ananalytical model is represented and it is also posed the problemofthe analyticaldetermination ofthe requiredarea of heat exchangewith the use ofdifferential equations ofheat transfer in amovingliquid media, written in cylindrical coordinates, for symmetrical temperature distribution,without taking into accountthe energy dissipation.

  14. Softenin, a novel protein that softens the connective tissue of sea cucumbers through inhibiting interaction between collagen fibrils.

    Directory of Open Access Journals (Sweden)

    Yasuhiro Takehana

    Full Text Available The dermis in the holothurian body wall is a typical catch connective tissue or mutable collagenous tissue that shows rapid changes in stiffness. Some chemical factors that change the stiffness of the tissue were found in previous studies, but the molecular mechanisms of the changes are not yet fully understood. Detection of factors that change the stiffness by working directly on the extracellular matrix was vital to clarify the mechanisms of the change. We isolated from the body wall of the sea cucumber Stichopus chloronotus a novel protein, softenin, that softened the body-wall dermis. The apparent molecular mass was 20 kDa. The N-terminal sequence of 17 amino acids had low homology to that of known proteins. We performed sequential chemical and physical dissections of the dermis and tested the effects of softenin on each dissection stage by dynamic mechanical tests. Softenin softened Triton-treated dermis whose cells had been disrupted by detergent. The Triton-treated dermis was subjected to repetitive freeze-and-thawing to make Triton-Freeze-Thaw (TFT dermis that was softer than the Triton-treated dermis, implying that some force-bearing structure had been disrupted by this treatment. TFT dermis was stiffened by tensilin, a stiffening protein of sea cucumbers. Softenin softened the tensilin-stiffened TFT dermis while it had no effect on the TFT dermis without tensilin treatment. We isolated collagen from the dermis. When tensilin was applied to the suspending solution of collagen fibrils, they made a large compact aggregate that was dissolved by the application of softenin or by repetitive freeze-and-thawing. These results strongly suggested that softenin decreased dermal stiffness through inhibiting cross-bridge formation between collagen fibrils; the formation was augmented by tensilin and the bridges were broken by the freeze-thaw treatment. Softenin is thus the first softener of catch connective tissue shown to work on the cross

  15. Milk protein-gum tragacanth mixed gels: effect of heat-treatment sequence.

    Science.gov (United States)

    Hatami, Masoud; Nejatian, Mohammad; Mohammadifar, Mohammad Amin; Pourmand, Hanieh

    2014-01-30

    The aim of this study was to investigate the role of the heat-treatment sequence of biopolymer mixtures as a formulation parameter on the acid-induced gelation of tri-polymeric systems composed of sodium caseinate (Na-caseinate), whey protein concentrate (WPC), and gum tragacanth (GT). This was studied by applying four sequences of heat treatment: (A) co-heating all three biopolymers; (B) heating the milk-protein dispersion and the GT dispersion separately; (C) heating the dispersion containing Na-caseinate and GT together and heating whey protein alone; and (D) co-heating whey protein with GT and heating Na-caseinate alone. According to small-deformation rheological measurements, the strength of the mixed-gel network decreased in the order: C>B>D>A samples. SEM micrographs show that the network of sample C is much more homogenous, coarse and dense than sample A, while the networks of samples B and D are of intermediate density. The heat-treatment sequence of the biopolymer mixtures as a formulation parameter thus offers an opportunity to control the microstructure and rheological properties of mixed gels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Effect of Pressure and Heat Treatments on the Compressive Strength of Reactive Powder Concrete

    Directory of Open Access Journals (Sweden)

    Helmi Masdar

    2018-01-01

    Full Text Available This paper presents the corresponding compressive strength of RPC with variable pressure combined with heating rate, heating duration, and starting time of heating. The treatments applied were 8 MPa static pressure on fresh RPC prims and heat curing at 240 °C in an oven. The compressive strength test was conducted at 7-d and 28-d. The images of RPC morphology were captured on the surface of a fractured specimen using Scanning Electron Microscopy in Secondary Electron detector mode to describe pore filing mechanism after treatments. The results show that a heating rate at 50 °C/hr resulted in the highest compressive strength about 40 % more than those at 10 or 100 °C/hr. A heating duration of 48 hours led to the maximum compressive strength. Heat curing applied 2 days after casting resulted in the maximum compressive. Heat curing had a signicant effect on the compresssive strength due to the acceleration of both reactions (hydration and pozzolanic and the degree of transformation from tobermorite to xonotlite. It is concluded that the optimum condition of treatments is both pressure and heat curing at 2-day after casting with a rate of 50 °C/hr for 48 hours.

  17. Stone heat treatment in the Early Mesolithic of southwestern Germany: Interpretation and identification.

    Directory of Open Access Journals (Sweden)

    Patrick Schmidt

    Full Text Available The Early Mesolithic of southwestern Germany, the so-called Beuronian (9600-7100 BC, is a period of important transformations in the way people lived, in their subsistence and in the stone tools they produced. One of the perhaps most spectacular re-inventions of that time is heat treatment of stones prior to their manufacture into tools. Although heat treatment has been understood as one of the defining characteristics of the Beuronian of southwestern Germany, and although its existence has been known for almost 30 years now, relatively few systematic studies on it are available. In this paper, we present such a study, aiming to shed light on two questions: (1 what technique and heating parameters were used in the Beuronian and (2 how reliable are the macroscopic proxies traditionally used to identify heat treatment in this context? We investigate these questions using a non-destructive archaeometric technique for measuring past heating temperatures of heat-treated stones and a quantitative surface roughness analysis aiming to understand the relations between surface aspect and heat treatment. These methods are applied to 46 Jurassic chert artefacts from the site Helga-Abri located in the Swabian Alb region of southwestern Germany. Our results document that an opportunistic low-investment procedure was used to heat stone, probably relying on the use of the above-ground part of regular camp-fires. We also found that the traditionally used macroscopic criteria, such as colour and surface gloss, cannot be unambiguously used to identify heat treatment in assemblages made from Jurassic chert. These findings have important implications for our understanding of the Beuronian lithic chaîne opératoire in terms of the investment in time and resources necessary, and for the refinement of archaeological techniques used to identify heat treatment in the Mesolithic of the Swabian Alb.

  18. Stone heat treatment in the Early Mesolithic of southwestern Germany: Interpretation and identification.

    Science.gov (United States)

    Schmidt, Patrick; Spinelli Sanchez, Océane; Kind, Claus-Joachim

    2017-01-01

    The Early Mesolithic of southwestern Germany, the so-called Beuronian (9600-7100 BC), is a period of important transformations in the way people lived, in their subsistence and in the stone tools they produced. One of the perhaps most spectacular re-inventions of that time is heat treatment of stones prior to their manufacture into tools. Although heat treatment has been understood as one of the defining characteristics of the Beuronian of southwestern Germany, and although its existence has been known for almost 30 years now, relatively few systematic studies on it are available. In this paper, we present such a study, aiming to shed light on two questions: (1) what technique and heating parameters were used in the Beuronian and (2) how reliable are the macroscopic proxies traditionally used to identify heat treatment in this context? We investigate these questions using a non-destructive archaeometric technique for measuring past heating temperatures of heat-treated stones and a quantitative surface roughness analysis aiming to understand the relations between surface aspect and heat treatment. These methods are applied to 46 Jurassic chert artefacts from the site Helga-Abri located in the Swabian Alb region of southwestern Germany. Our results document that an opportunistic low-investment procedure was used to heat stone, probably relying on the use of the above-ground part of regular camp-fires. We also found that the traditionally used macroscopic criteria, such as colour and surface gloss, cannot be unambiguously used to identify heat treatment in assemblages made from Jurassic chert. These findings have important implications for our understanding of the Beuronian lithic chaîne opératoire in terms of the investment in time and resources necessary, and for the refinement of archaeological techniques used to identify heat treatment in the Mesolithic of the Swabian Alb.

  19. Reactions of lactose during heat treatment of milk : a quantitative study

    NARCIS (Netherlands)

    Berg, H.E.

    1993-01-01

    The kinetics of the chemical reactions of lactose during heat treatment of milk were studied. Skim milk and model solutions resembling milk were heated. Reaction products were determined and the influence of varying lactose, casein and fat concentration on the formation of these products

  20. Preparation, heat treatment, and mechanical properties of the uranium-5 weight percent chromium eutectic alloy

    International Nuclear Information System (INIS)

    Townsend, A.B.

    1980-10-01

    The eutectic alloy of uranium-5 wt % chromium (U-5Cr) was prepared from high-purity materials and cast into 1-in.-thick ingots. This material was given several simple heat treatments, the mechanical properties of these heat-treated samples were determined; and the microstructure was examined. Some data on the melting point and transformation temperatures were obtained

  1. Effect of Heat Treatment on the Lycopene Content of Tomato Puree ...

    African Journals Online (AJOL)

    Effect of Heat Treatment on the Lycopene Content of Tomato Puree. MI Mohammed, DI Malami. Abstract. Lycopene is a powerful antioxidant. Epidemiological studies have associated its consumption with numerous health benefits. In this study the effects of heating on lycopene were investigated by exposing tomato ...

  2. Improved corrosion resistance of aluminum brazing sheet by a post-brazing heat treatment

    NARCIS (Netherlands)

    Norouzi Afshar, F.; Tichelaar, F.D.; Glenn, A. M.; Taheri, P.; Sababi, M.; Terryn, H.A.; Mol, J.M.C.

    2017-01-01

    This work studies the influence of the microstructure on the corrosion mechanism and susceptibility of as-brazed aluminum sheet. Various microstructures are obtained using postbrazing heat treatments developed to enhance the corrosion resistance of an AA4xxx/AA3xxx brazing sheet. The heat

  3. Simulation of Distortion and Residual Stress Development During Heat Treatment of Steel Castings

    Energy Technology Data Exchange (ETDEWEB)

    Beckermann, Christoph; Carlson, Kent

    2011-07-22

    Heat treatment and associated processing, such as quenching, are critical during high strength steel casting production. These processes must be managed closely to prevent thermal and residual stresses that may result in distortion, cracking (particularly after machining), re-work, and weld repair. The risk of casting distortion limits aggressive quenching that can be beneficial to the process and yield an improved outcome. As a result of these distortions, adjustments must be made to the casting or pattern design, or tie bars must be added. Straightening castings after heat treatments can be both time-consuming and expensive. Residual stresses may reduce a casting's overall service performance, possibly resulting in catastrophic failure. Stress relieving may help, but expends additional energy in the process. Casting software is very limited in predicting distortions during heat treatment, so corrective measures most often involve a tedious trial-and-error procedure. An extensive review of existing heat treatment residual stress and distortion modeling revealed that it is vital to predict the phase transformations and microstructure of the steel along with the thermal stress development during heat treatment. After reviewing the state-of-the-art in heat treatment residual stress and distortion modeling, an existing commercial code was selected because of its advanced capabilities in predicting phase transformations, the evolving microstructure and related properties along with thermal stress development during heat treatment. However, this software was developed for small parts created from forgings or machined stock, and not for steel castings. Therefore, its predictive capabilities for heat treatment of steel castings were investigated. Available experimental steel casting heat treatment data was determined to be of insufficient detail and breadth, and so new heat treatment experiments were designed and performed, casting and heat treating modified versions

  4. Heat Transfer treatment in computer codes for safety analysis

    International Nuclear Information System (INIS)

    Jerele, A.; Gregoric, M.

    1984-01-01

    Increased number of operating nuclear power plants has stressed importance of nuclear safety evaluation. For this reason, accordingly to regulatory commission request, safety analyses with computer codes are preformed. In this paper part of this thermohydraulic models dealing with wall-to-fluid heat transfer correlations in computer codes TRAC=PF1, RELAP4/MOD5, RELAP5/MOD1 and COBRA-IV is discussed. (author)

  5. Development of the heat treatment system for the 40 T hybrid magnet superconducting outsert.

    Science.gov (United States)

    Chen, W G; Chen, Z M; Chen, Z Y; Huang, P C; He, P; Zhu, J W

    2011-10-01

    The heat treatment of Nb(3)Sn coil with the glass fabric insulation is one of the key and critical processes for the outsert solenoids of the 40 T hybrid magnet, which could be wound with cable-in-conduit conductors using the insulation-wind-and-react technique. The manufacturing of the large vertical type vacuum/Ar atmosphere-protection heat treatment system has been completed and recently installed in the High Magnetic Filed Laboratory, Chinese Academy of Sciences. The heat treatment system composed mainly the furnace, the purging gas supply system, the control system, the gas impurities monitoring system, and so on. At present, the regulation and testing of the heat treatment system has been successfully finished, and all of technical parameters meet or exceed specifications.

  6. Effects of Mead Wort Heat Treatment on the Mead Fermentation Process and Antioxidant Activity.

    Science.gov (United States)

    Czabaj, Sławomir; Kawa-Rygielska, Joanna; Kucharska, Alicja Z; Kliks, Jarosław

    2017-05-14

    The effects of mead wort heat treatment on the mead fermentation process and antioxidant activity were tested. The experiment was conducted with the use of two different honeys (multiflorous and honeydew) collected from the Lower Silesia region (Poland). Heat treatment was performed with the use of a traditional technique (gently boiling), the more commonly used pasteurization, and without heat treatment (control). During the experiment fermentation dynamics were monitored using high performance liquid chromatography with refractive index detection (HPLC-RID). Total antioxidant capacity (TAC) and total phenolic content (TPC) were estimated for worts and meads using UV/Vis spectrophotometric analysis. The formation of 5-hydroxymethylfurfural (HMF) was monitored by HPLC analyses. Heat treatment had a great impact on the final antioxidant capacity of meads.

  7. Effect of Carbon Nanofiber Heat Treatment on Physical Properties of Polymeric Nanocomposites—Part I

    Directory of Open Access Journals (Sweden)

    Khalid Lafdi

    2007-01-01

    Full Text Available The definition of a nanocomposite material has broadened significantly to encompass a large variety of systems made of dissimilar components and mixed at the nanometer scale. The properties of nanocomposite materials also depend on the morphology, crystallinity, and interfacial characteristics of the individual constituents. In the current work, vapor-grown carbon nanofibers were subjected to varying heat-treatment temperatures. The strength of adhesion between the nanofiber and an epoxy (thermoset matrix was characterized by the flexural strength and modulus. Heat treatment to 1800C∘ demonstrated maximum improvement in mechanical properties over that of the neat resin, while heat-treatment to higher temperatures demonstrated a slight decrease in mechanical properties likely due to the elimination of potential bonding sites caused by the elimination of the truncated edges of the graphene layers. Both the electrical and thermal properties of the resulting nanocomposites increased in conjunction with the increasing heat-treatment temperature.

  8. Experimental heat treatment of silcrete implies analogical reasoning in the Middle Stone Age.

    Science.gov (United States)

    Wadley, Lyn; Prinsloo, Linda C

    2014-05-01

    Siliceous rocks that were not heated to high temperatures during their geological formation display improved knapping qualities when they are subjected to controlled heating. Experimental heat treatment of South African silcrete, using open fires of the kind used during the Middle Stone Age, shows that the process needed careful management, notwithstanding recent arguments to the contrary. Silcrete blocks fractured when heated on the surface of open fires or on coal beds, but were heated without mishap when buried in sand below a fire. Three silcrete samples, a control, a block heated underground with maximum temperature between 400 and 500 °C and a block heated in an open fire with maximum temperature between 700 and 800 °C, were analysed with X-ray powder diffraction (XRD), X-ray fluorescence (XRF), optical microscopy, and both Fourier transform infrared (FTIR) and Raman spectroscopy. The results show that the volume expansion during the thermally induced α- to β-quartz phase transformation and the volume contraction during cooling play a major role in the heat treatment of silcrete. Rapid heating or cooling through the phase transformation at 573 °C will cause fracture of the silcrete. Successful heat treatment requires controlling surface fire temperatures in order to obtain the appropriate underground temperatures to stay below the quartz inversion temperature. Heat treatment of rocks is a transformative technology that requires skilled use of fire. This process involves analogical reasoning, which is an attribute of complex cognition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Internal friction and elastic softening in polycrystalline Nb3Sn

    International Nuclear Information System (INIS)

    Bussiere, J.F.; Faucher, B.; Snead, C.L. Jr.; Welch, D.O.

    1981-01-01

    The vibrating-reed technique was used to measure internal friction and Young's modulus of polycrystalline Nb 3 Sn in the form of composite Nb/Nb 3 Sn tapes from 6 to 300 K. In tapes with only small residual strain in the A15 layers, a dramatic increase in internal friction with decreasing temperature is observed with an abrupt onset at approx.48 K. The internal friction Q -1 between 6 and 48 K is believed to be associated with stress-induced motion of martensitic-domain walls. In this temperature range, Q -1 is approximately proportional to the square of the tetragonal strain of the martensitic phase; Q -1 α (c/a-1) 2 . With residual compressive strains of approx.0.2%, the internal friction associated with domain-wall motion is considerably reduced. This is attributed to a biasing of domain-wall orientation with residual stress, which reduces wall motion induced by the (much smaller) applied stress. The transformation temperature, however, is unchanged (within +- 1 K) by residual strains of up to 0.2%. Young's modulus exhibits substantial softening on cooling from 300 to 6 K. This softening, is substantially reduced in the presence of small residual compressive strains, indicating a highly nonlinear stress-strain relationship as previously reported for V 3 Si

  10. Influence of Heat Treatment on the Corrosion Behavior of Purified Magnesium and AZ31 Alloy

    OpenAIRE

    Khalifeh, Sohrab; Burleigh, T. David

    2017-01-01

    Magnesium and its alloys are ideal for biodegradable implants due to their biocompatibility and their low-stress shielding. However, they can corrode too rapidly in the biological environment. The objective of this research was to develop heat treatments to slow the corrosion of high purified magnesium and AZ31 alloy in simulated body fluid at 37{\\deg}C. Heat treatments were performed at different temperatures and times. Hydrogen evolution, weight loss, PDP, and EIS methods were used to measu...

  11. Regularities of texture formation in alloys undergoing phase transformations during heat treatment and plastic working

    International Nuclear Information System (INIS)

    Ageev, N.V.; Babarehko, A.A.

    1983-01-01

    Peculiarities of texture formation in metals undergoing phase transformations in the temperature range of heat treatment and hot working are investigated theoretically and experimentally. A low-temperature phase after hot working is shown to inherite a high-temperature phase texture due to definite orientation conformity during phase transformation. Strengthened heat and thermomechanical treatments, as a rule, do not destroy material texture but change it

  12. Synergistic effects of heat and irradiation treatment (thermoradiation) in the sterilization of medical products

    International Nuclear Information System (INIS)

    Trauth, C.A. Jr.; Sivinski, H.D.

    1975-01-01

    This paper describes a generic class of sterilization processes is which properly chosen combinations of radiation and heat synergistically inactivate many bacteria and viruses. Treatments with optimal combinations are shown to offer the possibility of using lower total doses and lower temperatures than would be required separately for sterilization. This results from easier elimination of heat-labile, radioresistant organisms and radiolabile, heat-resistant organisms, and from synergistic inactivation of organisms which are both radioresistant and heat resistant. These processes depend upon temperature, dose-rate, and time in fairly complex ways; therefore, an analytical framework in which they can be defined is also presented. (author)

  13. Evaluation of the Characteristics of the Aluminum Alloy Casting Material by Heat Treatment

    International Nuclear Information System (INIS)

    Lee, Syung Yul; Park, Dong Hyun; Won, Jong Pil; Kim, Yun Hae; Lee, Myung Hoon; Moon, Kyung Man; Jeong, Jae Hyun

    2012-01-01

    Aluminum is on active metal, but it is well known that its oxide film plays a role as protective barrier which is comparatively stable in air and neutral aqueous solution. Thus, aluminum alloys have been widely applied in architectural trim, cold and hot-water storage vessels and piping etc., furthermore, the aluminum alloy of AC8A have been widely used in mold casting material of engine piston because of its properties of temperature and wear resistance. In recent years, the oil price is getting higher and higher, thus the using of low quality oil has been significantly increased in engines of ship and vehicle. Therefore it is considered that evaluation of corrosion resistance as well as wear resistance of AC8A material is also important to improve its property and prolong its lifetime. In this study, the effect of solution and tempering heat treatment to corrosion and wear resistance is investigated with electrochemical method and measurement of hardness. The hardness decreased with solution heat treatment compared to mold casting condition, but its value increased with tempering heat treatment and exhibited the highest value of hardness with tempering heat treatment temperature at 190 .deg. C for 24hrs. Furthermore, corrosion resistance increased with decreasing of the hardness, and decreased with increasing of the hardness reversely. As a result, it is suggested that the optimum heat treatment to improve both corrosion and wear resistance is tempering heat treatment temperature at 190 .deg. C for 16hrs

  14. Static softening following multistage hot deformation of 7150 aluminum alloy: Experiment and modeling

    International Nuclear Information System (INIS)

    Jiang, Fulin; Zurob, Hatem S.; Purdy, Gary R.; Zhang, Hui

    2015-01-01

    Previous studies have demonstrated that the static softening kinetics of 7150 aluminum alloy showed typical sigmoidal behavior at 400 °C and softening plateaus at 300 °C (F.L. Jiang, et al., Mater. Sci. Eng. A, vol. 552, 2012, pp. 269–275). In present work, the static softening mechanisms, the microstructural evolution during post-deformation holding was studied by optical microscopy, scanning electron microscope, electron back-scattered diffraction and transmission electron microscopy. It was demonstrated that recrystallization is essentially absent during post-deformation holding, and that static recovery was the main contribution to static softening. Strain induced precipitation and coarsening caused softening plateaus at 300 °C. In order to better understand the static softening mechanism, physically-based modeling, which integrated recovery and multicomponent particle coarsening modeling, was employed to rationalize the experimental results.

  15. Aging of iron (hydr)oxides by heat treatment and effects on heavy metal binding

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Starckpoole, M. M.; Frenkel, A. I.

    2000-01-01

    their transformations caused by heat treatment prior to disposal or aging at a proper disposal site. The transformations were investigated by XRD, SEM, XANES, EXAFS, surface area measurements, pH static leaching tests, and extractions with oxalate and weak hydrochloric acid. It was found that at 600 and 900 °C the iron...... oxides were transformed to hematite, which had a greater thermodynamic stability but less surface area than the initial products. Heat treatment also caused some volatilization of heavy metals (most notably, Hg). Leaching with water at pH 9 (L/S 10, 24 h) and weak acid extraction showed that heat...

  16. Heat Treatment of Cr- and Cr-V ledeburitic tool steels

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2014-11-01

    Full Text Available Cr- and Cr-V ledeburitic cold work tool steels belong to the most important tool materials for large series manufacturing. To enable high production stability, the tools must be heat treated before use. This overview paper brings a comprehensive study on the heat treatment of these materials, starting from the soft annealing and finishing with the tempering. Also, it describes the impact of any step of the heat treatment on the most important structural and mechanical characteristics, like the hardness, the toughness and the wear resistance. The widely used AIS D2- steel (conventionally manufactured and Vanadis 6 (PM are used as examples in most cases.

  17. Study of tokamaks carbon deposits after heat treatment

    International Nuclear Information System (INIS)

    Richou, M.; Martin, C.; Roubin, P.; Delhaes, P.; Couzi, M.; Brosset, C.; Pegourie, B.

    2006-01-01

    One of the most important problem of tokamak is the interaction plasma-wall. The wall component is the graphite. Meanwhile it is submitted to erosion phenomena, deposition and co-deposition with the hydrogen. This carbon deposits have been studied and show an oval shape. In order to obtain more information on the structure and the growth of these deposits, the authors heated them till 2500 C. Raman spectroscopy, transmission microscopy, magnetic and density measurements have been realized and compared for two types of samples: from Tore Supra and from Textor. (A.L.B.)

  18. Hydrogenated amorphous carbon next deposit after heat treatment

    International Nuclear Information System (INIS)

    Salancon, E.; Durbeck, T.; Schwarz-Selinger, T.; Jacob, W.

    2006-01-01

    One of the main safety problems in the ITER tokamak project is the tritium adsorption in the reactor walls and in particular the deposits which appear after the plasma discharge. These deposits are amorphous hydrogenated carbon films, type polymer (soft a-C:H). The heating of these deposits with a pulse laser is a proposed solution for the tritium desorption. Meanwhile, Gibson and al show that in experimental conditions, products are deposed on the walls before entering the mass spectrometer. The authors present thermo-desorption spectra of different amorphous carbon films. (A.L.B.)

  19. Effect of alkali and heat treatments for bioactivity of TiO{sub 2} nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seo young, E-mail: mast6269@nate.com [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Kim, Yu kyoung, E-mail: yk0830@naver.com [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Park, Il song, E-mail: ilsong@jbnu.ac.kr [Division of Advanced Materials Engineering, Research Center for Advanced Materials Development and Institute of Biodegradable Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Jin, Guang chun, E-mail: jingc88@126.com [Oral Medical College, Beihua University, Jilin City 132013 (China); Bae, Tae sung, E-mail: bts@jbnu.ac.kr [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Lee, Min ho, E-mail: mh@jbnu.ac.kr [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of)

    2014-12-01

    Highlights: • TiO{sub 2} nanotubes formed via anodization were treated by alkali and heat. • The surface roughness was increased after alkali treatment (p < 0.05). • After alkali and heat treatment, the wettability was better than before treatment. • Alkali treated TiO{sub 2} nanotubes were shown higher HAp formation in SBF. • Heat treatment affected on the attachment of cells for alkali treated nanotubes. - Abstract: In this study, for improving the bioactivity of titanium used as an implant material, alkali and heat treatments were carried out after formation of the nanotubes via anodization. Nanotubes with uniform length, diameter, and thickness were formed by anodization. The alkali and heat-treated TiO{sub 2} nanotubes were covered with the complex network structure, and the Na compound was generated on the surface of the specimens. In addition, after 5 and 10 days of immersion in the SBF, the crystallized OCP and HAp phase was significantly increased on the surface of the alkali-treated TiO{sub 2} nanotubes (PNA) and alkali and heat-treated TiO{sub 2} nanotubes (PNAH) groups. Cell proliferation was decreased due to the formation of amorphous sodium titanate (Na{sub 2}TiO{sub 3}) layer on the surface of the PNA group. However, anatase and crystalline sodium titanate were formed on the surface of the PNAH group after heat treatment at 550 °C, and cell proliferation was improved. Thus, PNA group had higher HAp forming ability in the simulated body fluid. Additional heat treatment affected on enhancement of the bioactivity and the attachment of osteoblasts for PNA group.

  20. Heat treatment of large-sized welded rotors of steam turbines for atomic power stations

    Energy Technology Data Exchange (ETDEWEB)

    Kutasov, R F; Mukhina, M P; Tustanovskii, A S

    1977-01-01

    The heat treatment of a welded rotor of grade 25Kh2NMFA steel for steam turbines of nuclear power plants was considered. A following heat treatment schedule was suggested: charging the rotor in to a furnace at 100-150 deg C, heating to 200-250 deg C and holding for 12 hrs; slow heating (10 deg C/h) to 400-450 deg C and holding for 12 hrs; slow heating to 630-640 deg C and holding for 50 hrs, cooling at a rate of 5 deg C/h down to 100 deg C, holding for 20 hrs and cooling with the furnace open. The proposed heat treatment schedule of a duration of 356 hrs ensures a temperature gradient throughout the cross section and the length of the rotor of not more than +-5 deg C, least deviations of geometric dimensions and makes possible machining finish to within 0-0.02 mm. Described are the particularities of the design of a roll-out hearth electric chamber furnace, measuring 13000x5500x5000 mm and built for the purpose of carrying out said heat treatment. The power rating of the furnace is 2850 kW.

  1. Corrosion performance of 7075 alloy under laser heat treatment

    Science.gov (United States)

    Liu, Tong; Su, Ruiming; Qu, Yingdong; Li, Rongde

    2018-05-01

    Microstructure, exfoliation corrosion (EXCO), intergranular corrosion (IGC) and potentidynamic polarization test of the 7075 aluminum alloy after retrogression and re-aging (RRA) treatment, and laser retrogression and re-aging (LRRA), respectively, were studied by using scanning electron microscope, and transmission electron microscope (TEM). The results show that after pre-aging, laser treatment (650 W, 2 mm s‑1) and re-aging a lot of matrix precipitates of alloy were precipitated again. The semi-continuous grain boundary precipitates and the wider precipitate-free zones (PFZ) improve the corrosion resistance of the alloy. The corrosion properties of the alloy after LRRA (650 W, 2 mm s‑1) treatment are better than that after RRA treatment.

  2. Effects of heat treatment temperature on morphology and properties of opal crystal

    International Nuclear Information System (INIS)

    Duan Tao; China Academy of Engineering Physics, Mianyang; Peng Tongjiang; Chen Jiming; Tang Yongjian

    2008-01-01

    The monodispersed SiO 2 microspheres were synthesized by reactant mixed equally. The colloid crystal templates were assemblied by vertical sedimentation method in ethanol at certain temperatures, and the effects of the heat treatment temperature on the morphology and the properties of opal colloid crystals were investigated. SEM, TCr-DSC results indicate SiO 2 colloid templates should be heat treated at 700-800 degree C, enhancing the conglutination and mechanistic intensity of opal templates. UV-Vis analysis result indicates that the heat treatment process can remove the photonic band gap location of the opal colloid crystals, and with the heat treatment temperature increasing gradually, blue shift occurs and the gap narrows. (authors)

  3. UV-Heat Treatments for the Control of Foodborne Microbial Pathogens in Chicken Broth

    Directory of Open Access Journals (Sweden)

    M. Gouma

    2015-01-01

    Full Text Available This investigation established the process criteria for using UV-C light and mild heat (UV-H treatment to inactivate 5-Log10 cycles (performance criterion of common foodborne pathogen populations, Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus, when inoculated in chicken broth. To define the target microorganism and the proper UV-H treatment conditions (including UV dose, treatment time, and temperature that would achieve the stated performance criterion, mathematical equations based on Geeraerd’s model were developed for each microorganism. For the sake of comparison, inactivation equations for heat treatments were also performed on the same chicken broth and for the same microorganisms. L. monocytogenes was the most UV-H resistant microorganism at all temperatures, requiring a UV dose between 6.10 J/mL (5.6 min and 2.26 J/mL (2.09 min to achieve 5-Log10 reductions. In comparison with UV treatments at room temperatures, the combination of UV and mild heat allowed both the UV dose and treatment time to be reduced by 30% and 63% at 55°C and 60°C, respectively. Compared to heat treatments, the UV-H process reduced the heating time for 5-Log10 reductions of all the investigated microorganisms in chicken broth from 20-fold to 2-fold when the operating temperature varied from 53 to 60°C.

  4. Effect of heat treatment operations on the Rm tensile strength of silumins

    Directory of Open Access Journals (Sweden)

    J. Pezda

    2010-10-01

    Full Text Available Owing to good technological properties, low weight and good corrosion resistance, aluminum-silicon alloys are widely used as a material for cast machinery components. State of macro- and microstructure of a castings manufactured from Al-Si alloys, which is determined by a shape and distribution of hardening phases, segregation of alloying constituents and impurities, as well as distribution of porosity, create conditions to obtainment of proper mechanical properties. These properties can be improved through modification of the alloy and performed heat treatment operations. The paper presents effect of modification and heat treatment process on the Rm tensile strength of a selected silumins (EN AB-AlSi9Cu3(Fe, EN AB-AlSi12CuNiMg, EN AB-AlSi17Cu1Ni1Mg. Investigated alloys were put to treatments of refining and modification, and next to heat treatment. Temperature range of the heat treatment operations was determined on base of curves from the ATD method. Obtained results illustrate registered curves of melting and solidification from the ATD method and strength tests. On base of performed initial tests one determined parameters of the heat treatment process (temperature and duration of solutionig and ageing treatments enabling obtainment of improved Rm tensile strength of the investigated alloys.

  5. Impact of Heat-Shock Treatment on Yellowing of Pak Choy Leaves

    Institute of Scientific and Technical Information of China (English)

    WANG Xiang-yang; SHEN Lian-qing; YUAN Hai-na

    2004-01-01

    The physiological mechanism of maintaining the green colour of pak choy leaves (Brassica rapa var chinensis) with heat-shock treatment was studied. Chlorophyll in the outer leaves of pak choy degraded rapidly during storage at ambient temperature (20 ± 2℃), a slight yellow appeared. Heat-shock treatment (46- 50℃) had a mild effect on maintaining the green colour of outer leaves. Normal chlorophyll degradation was associated with a binding of chlorophyll with chlorophyll-binding-protein preceding chlorophyll breakdown.Heat-shock treatment was found to reduce the binding-capacity between chlorophyllbinding-protein and chlorophyll. In the chlorophyll degradation pathway, pheide dioxygenase was synthesized during leaf senescence which was considered to be a key enzyme in chlorophyll degradation. Activity of this enzyme was reduced following heat-shock treatment, which might explain the observed reduction in chlorophyll breakdown. Two groups of heat-shock proteins were detected in treated leaves, the first group containing proteins from 54KDa to 74 Kda, and the second group contained proteins from 15 KDa to 29KDa. Heat-shock treatment was also found to retard the decline of glucose and fructose (the main energy substrates) of outer leaves.

  6. A previously undescribed organic residue sheds light on heat treatment in the Middle Stone Age.

    Science.gov (United States)

    Schmidt, Patrick; Porraz, Guillaume; Bellot-Gurlet, Ludovic; February, Edmund; Ligouis, Bertrand; Paris, Céline; Texier, Pierre-Jean; Parkington, John E; Miller, Christopher E; Nickel, Klaus G; Conard, Nicholas J

    2015-08-01

    South Africa has in recent years gained increasing importance for our understanding of the evolution of 'modern human behaviour' during the Middle Stone Age (MSA). A key element in the suite of behaviours linked with modern humans is heat treatment of materials such as ochre for ritual purposes and stone prior to tool production. Until now, there has been no direct archaeological evidence for the exact procedure used in the heat treatment of silcrete. Through the analysis of heat-treated artefacts from the Howiesons Poort of Diepkloof Rock Shelter, we identified a hitherto unknown type of organic residue - a tempering-residue - that sheds light on the processes used for heat treatment in the MSA. This black film on the silcrete surface is an organic tar that contains microscopic fragments of charcoal and formed as a residue during the direct contact of the artefacts with hot embers of green wood. Our results suggest that heat treatment of silcrete was conducted directly using an open fire, similar to those likely used for cooking. These findings add to the discussion about the complexity of MSA behaviour and appear to contradict previous studies that had suggested that heat treatment of silcrete was a complex (i.e., requiring a large number of steps for its realization) and resource-consuming procedure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Study on Spheroidization and Related Heat Treatments of Medium Carbon Alloy Steels

    Directory of Open Access Journals (Sweden)

    Harisha S. R.

    2018-01-01

    Full Text Available The importance of medium carbon steels as engineering materials is reflected by the fact that out of the vast majority of engineering grade ferrous alloys available and used in the market today, a large proportion of them are from the family of medium carbon steels. Typically medium carbon steels have a carbon range of 0.25 to 0.65% by weight, and a manganese content ranging from 0.060 to 1.65% by weight. Medium carbon steels are more resistive to cutting, welding and forming as compared to low carbon steels. From the last two decades a number of research scholars reported the use of verity of heat treatments to tailor the properties of medium carbon steels. Spheroidizing is the novel industrial heat treatment employed to improve formability and machinability of medium/high carbon low alloy steels. This exclusive study covers procedure, the effects and possible outcomes of various heat treatments on medium carbon steels. In the present work, other related heat treatments like annealing and special treatments for property alterations which serve as pretreatments for spheroidizing are also reviewed. Medium carbon steels with property alterations by various heat treatment processes are finding increased responsiveness in transportation, aerospace, space, underwater along with other variegated fields. Improved tribological and mechanical properties consisting of impact resistance, stiffness, abrasion and strength are the main reasons for the increased attention of these steels in various industries. In the present scenario for the consolidation of important aspects of various heat treatments and effects on mechanical properties of medium carbons steel, a review of different research papers has been attempted. This review may be used as a guide to provide practical data for heat treatment industry, especially as a tool to enhance workability and tool life.

  8. Combined heat transfer and kinetic models to predict cooking loss during heat treatment of beef meat.

    Science.gov (United States)

    Kondjoyan, Alain; Oillic, Samuel; Portanguen, Stéphane; Gros, Jean-Bernard

    2013-10-01

    A heat transfer model was used to simulate the temperature in 3 dimensions inside the meat. This model was combined with a first-order kinetic models to predict cooking losses. Identification of the parameters of the kinetic models and first validations were performed in a water bath. Afterwards, the performance of the combined model was determined in a fan-assisted oven under different air/steam conditions. Accurate knowledge of the heat transfer coefficient values and consideration of the retraction of the meat pieces are needed for the prediction of meat temperature. This is important since the temperature at the center of the product is often used to determine the cooking time. The combined model was also able to predict cooking losses from meat pieces of different sizes and subjected to different air/steam conditions. It was found that under the studied conditions, most of the water loss comes from the juice expelled by protein denaturation and contraction and not from evaporation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Searching for Terrain Softening near Mercury's North Pole

    Science.gov (United States)

    Cobian, P. S.; Vilas, F.; Lederer, S. M.; Barlow, N. G.

    2004-01-01

    In 1999, following the initial discovery of radar bright craters near both poles of Mercury measured the depth-todiameter (d/D) ratios of 170 impact craters in Mariner 10 images covering four different regions on Mercury s surface. Rapid softening of crater structure, indicated by lower d/D ratios, could indicate the possibility of subsurface water ice in Mercury's terrain originating from an internal source in the planet. Their study included 3 specific radar bright craters suggested to contain ice. They concluded that no terrain softening was apparent, and a rapidly emplaced exogenic water source was the most likely source for the proposed ice in these craters. Recent radar observations of the Mercurian North pole have pinpointed many additional radar bright areas with a resolution 10x better than previous radar measurements, and which correlate with craters imaged by Mariner 10. These craters are correlated with regions that are permanently shaded from direct sunlight, and are consistent with observations of clean water ice. We have expanded the initial study by Barlow et al. to include d/D measurements of 12 craters newly identified as radar bright at latitudes poleward of +80o. The radar reflectivity resemblances to Mars south polar cap and echoes from three icy Galilean satellites suggest that these craters too may have polar ice on Mercury. The effect of subsurface H20 on impact craters is a decrease in its d/D ratio, and softening of crater rims over a period of time. The study of Barlow et al., focused on determining the d/D ratios of 170 impact craters in the Borealis (north polar), Tolstoj (equatorial), Kuiper (equatorial), and Bach (south polar) quadrangles. This work focuses on the newly discovered radar bright craters, investigating their d/D ratios as an expansion of the earlier work..We compare our results to the statistical results from Barlow et al. here. With the upcoming Messenger spacecraft mission to Mercury, this is an especially timely study

  10. Changes in alpha-L-arabinofuranosidase activity in peel and pulp of banana (Musa sp.) fruits during ripening and softening.

    Science.gov (United States)

    Zhuang, Jun-Ping; Su, Jing; Li, Xue-Ping; Chen, Wei-Xin

    2007-04-01

    Arabinose is one of the most dynamic cell wall glycosyl residues released during fruit ripening, alpha-L-arabinofuranosidase (alpha-Arab) are major glycosidases that may remove arabinose units from fruit cell wall polysaccharides. To find out whether alpha-Arab plays important roles in banana fruit softening, the enzyme activities in peel and pulp, fruit firmness, respiration rate and ethylene release rate were assayed during banana softening. The results showed that alpha-Arab activities in banana pulp and peel increased slightly at the beginning of storage and reached their maxima when the fruit firmness decreased drastically, alpha-Arab activity increased by more than ten folds in both pulp and peel during ripening and alpha-Arab activities were higher in pulp than in peel. Treatment of banana fruits with ethylene absorbent postponed the time of reaching of its maxima of respiration and ethylene, enhanced the firmness of pup and decreased alpha-Arab activity in the peel and pulp. These results suggest that alpha-Arab induced the decrease of fruit firmness and played an important role in banana fruit softening, and its activity was regulated by ethylene.

  11. Development of shelf stable, processed, low acid food products using heat-irradiation combination treatments

    International Nuclear Information System (INIS)

    Minnaar, A.

    1998-01-01

    The amount of ionizing irradiation needed to sterilize low acid vegetable and starch products (with and without sauces) commercially impairs their sensorial and nutritive qualities, and use of thermal processes for the same purpose may also have an adverse effect on the product quality. A systematic approach to the establishment of optimized combination parameters was developed for heat-irradiation processing to produce high quality, shelf stable, low acid food products. The effects of selected heat, heat-irradiation combination and irradiation treatments on the quality of shelf stable mushrooms in brine and rice, stored at ambient temperature, were studied. From a quality viewpoint, use of heat-irradiation combination treatments favouring low irradiation dose levels offered a feasible alternative to thermally processed or radappertized mushrooms in brine. However, shelf stable rice produced by heat-irradiation combination treatments offered a feasible alternative only to radappertized rice from the standpoint of quality. The technical requirements for the heat and irradiation processing of a long grain rice cultivar from the United States of America oppose each other directly, thereby reducing the feasibility of using heat-irradiation combination processing to produce shelf stable rice. The stability of starch thickened white sauces was found to be affected severely during high dose irradiation and subsequent storage at ambient temperature. However, use of pea protein isolate as a thickener in white sauces was found to have the potential to maintain the viscosity of sauces for irradiated meat and sauce products throughout processing and storage. (author)

  12. Heat treatment of transparent Yb:YAG and YAG ceramics and its influence on laser performance

    Science.gov (United States)

    Fujioka, Kana; Mochida, Tetsuo; Fujimoto, Yasushi; Tokita, Shigeki; Kawanaka, Junji; Maruyama, Momoko; Sugiyama, Akira; Miyanaga, Noriaki

    2018-05-01

    Composite transparent ceramic materials are promising for improving the performance of high-average-power lasers. A combination of room-temperature bonding via surface treatment by a fast atom beam and diffusion bonding via heating, which effectively controls the ion diffusion distance near the interface, makes the laser materials suitable for a variety of oscillator/amplifier. During the heat treatment of yttrium aluminum garnet (YAG) ceramics, the Si ions in the solid solution of the sintering aid incorporated within the grains were seen to segregate at the grain boundary, resulting in an increase of scattering sites. The number density and size of the scattering sites strongly depended on the post-heating temperature rather than the heating time. Specifically, heating at 1300 °C did not affect the transmittance of the YAG ceramic, whereas both the size and number of scattering sites substantially increased with a heat treatment at 1400 °C. The laser oscillation experiment using cryogenically-cooled Yb:YAG ceramics exhibited heating temperature dependence of the slope efficiency owing to the increasing scattering loss.

  13. Design and performance of a new induction furnace for heat treatment of superconducting radiofrequency niobium cavities.

    Science.gov (United States)

    Dhakal, Pashupati; Ciovati, Gianluigi; Rigby, Wayne; Wallace, John; Myneni, Ganapati Rao

    2012-06-01

    Superconducting radio frequency (SRF) cavities made of high purity niobium (Nb) are the building blocks of many modern particle accelerators. The fabrication process includes several cycles of chemical and heat treatment at low (∼120 °C) and high (∼800 °C) temperatures. In this contribution, we describe the design and performance of an ultra-high-vacuum furnace which uses an induction heating system to heat treat SRF cavities. Cavities are heated by radiation from the Nb susceptor. By using an all-niobium hot zone, contamination of the Nb cavity by foreign elements during heat treatment is minimized and allows avoiding subsequent chemical etching. The furnace was operated up to 1400 °C with a maximum pressure of ∼1 × 10(-5) Torr and the maximum achievable temperature is estimated to be higher than 2000 °C. Initial results on the performance of a single cell 1.5 GHz cavity made of ingot Nb heat treated at 1200 °C using this new induction furnace and without subsequent chemical etching showed a reduction of the RF losses by a factor of ∼2 compared to cavities made of fine-grain Nb which underwent standard chemical and heat treatments.

  14. The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Mamum, Md Abdullah A. [Old Dominion Univ., Norfolk, VA (United States); Elmustafa, Abdelmageed A, [Old Dominion Univ., Norfolk, VA (United States); Stutzman, Marcy L. [JLAB, Newport News, VA (United States); Adderley, Philip A. [JLAB, Newport News, VA (United States); Poelker, Matthew [JLAB, Newport News, VA (United States)

    2014-03-01

    The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the uncoated stainless steel. An evaluation of coating composition suggests the presence of elemental titanium which could provide pumping and lead to an artificially low outgassing rate. The outgassing results are discussed in terms of diffusion-limited versus recombination-limited processes.

  15. Softening in Random Networks of Non-Identical Beams.

    Science.gov (United States)

    Ban, Ehsan; Barocas, Victor H; Shephard, Mark S; Picu, Catalin R

    2016-02-01

    Random fiber networks are assemblies of elastic elements connected in random configurations. They are used as models for a broad range of fibrous materials including biopolymer gels and synthetic nonwovens. Although the mechanics of networks made from the same type of fibers has been studied extensively, the behavior of composite systems of fibers with different properties has received less attention. In this work we numerically and theoretically study random networks of beams and springs of different mechanical properties. We observe that the overall network stiffness decreases on average as the variability of fiber stiffness increases, at constant mean fiber stiffness. Numerical results and analytical arguments show that for small variabilities in fiber stiffness the amount of network softening scales linearly with the variance of the fiber stiffness distribution. This result holds for any beam structure and is expected to apply to a broad range of materials including cellular solids.

  16. A truly Newtonian softening length for disc simulations

    Science.gov (United States)

    Huré, J.-M.; Trova, A.

    2015-02-01

    The softened point mass model is commonly used in simulations of gaseous discs including self-gravity while the value of associated length λ remains, to some degree, controversial. This `parameter' is however fully constrained when, in a discretized disc, all fluid cells are demanded to obey Newton's law. We examine the topology of solutions in this context, focusing on cylindrical cells more or less vertically elongated. We find that not only the nominal length depends critically on the cell's shape (curvature, radial extension, height), but it is either a real or an imaginary number. Setting λ as a fraction of the local disc thickness - as usually done - is indeed not the optimal choice. We then propose a novel prescription valid irrespective of the disc properties and grid spacings. The benefit, which amounts to 2-3 more digits typically, is illustrated in a few concrete cases. A detailed mathematical analysis is in progress.

  17. Direct Cytoskeleton Forces Cause Membrane Softening in Red Blood Cells

    Science.gov (United States)

    Rodríguez-García, Ruddi; López-Montero, Iván; Mell, Michael; Egea, Gustavo; Gov, Nir S.; Monroy, Francisco

    2015-01-01

    Erythrocytes are flexible cells specialized in the systemic transport of oxygen in vertebrates. This physiological function is connected to their outstanding ability to deform in passing through narrow capillaries. In recent years, there has been an influx of experimental evidence of enhanced cell-shape fluctuations related to metabolically driven activity of the erythroid membrane skeleton. However, no direct observation of the active cytoskeleton forces has yet been reported to our knowledge. Here, we show experimental evidence of the presence of temporally correlated forces superposed over the thermal fluctuations of the erythrocyte membrane. These forces are ATP-dependent and drive enhanced flickering motions in human erythrocytes. Theoretical analyses provide support for a direct force exerted on the membrane by the cytoskeleton nodes as pulses of well-defined average duration. In addition, such metabolically regulated active forces cause global membrane softening, a mechanical attribute related to the functional erythroid deformability. PMID:26083919

  18. Preliminary observations of heat treatment to control Phytophthora ramorum in infected wood species: an extended abstract

    Science.gov (United States)

    K.M. Tubajika; R. Singh; Shelly J.R.

    2008-01-01

    Identification of appropriate phytosanitary treatments that can be used for certifying solid wood packing material movement from areas infested or threatened by actionable plant pests and pathogens into uninfested areas is mportant. Heat treatment has been used on commodities to control fungal diseases and insect infestations for many years. The restricted use of...

  19. Do bark beetles and wood borers infest lumber following heat treatment? The role of bark

    Science.gov (United States)

    Robert A. Haack; Toby R. Petrice; Pascal Nzokou

    2007-01-01

    Wood packing material (WPM) is an important pathway for the movement of bark- and wood-infesting insects (Haack 2006). New international standards for treating WPM, often referred to as "ISPM 15," were adopted in 2002 (FAO 2002). The two approved WPM treatments are heat treatment (56? C core temperature for 30 min) and fumigation with methyl bromide. These...

  20. Effects of heat treatments on laser welded Mg-rare earth alloy NZ30K

    International Nuclear Information System (INIS)

    Dai Jun; Huang Jian; Li Min; Li Zhuguo; Dong Jie; Wu Yixiong

    2011-01-01

    Highlights: → Firstly find the tadpole-shape precipitates in the welding joint. → The precipitation strengthening can account for 79% of the total strength. → The results can provide some insights on the application of Mg-RE alloy. - Abstract: In this study, the effects of heat treatments on the quality of laser welded Mg-rare earth alloy NZ30K were systematically studied. The microstructure and mechanical properties of joints, welded by a 15 kW high power CO 2 laser, under different heat treatments had been tested and analyzed. The results indicated that the heat treatment plays an important role in the mechanical strength of laser welded joint of NZ30K. The microstructure of samples after the solution treatment as well as aging treatment is different from that of the as-received welded joint. For solution treatment, although the microstructure is much different from that of as-received welded joint, the solution strengthening effect is not obvious. There are lots of precipitates in the fusion zone after the aging treatment, which will significantly enhance the ultimate tensile strength (UTS) and the yield tensile strength (YTS) of the welding joint. 79% of YTS is caused by precipitation strengthening. Therefore, the results implied that the UTS and YTS can be greatly improved by proper heat treatment.

  1. Susceptibility of Plodia interpunctella (Lepidoptera: Pyralidae) developmental stages to high temperatures used during structural heat treatments.

    Science.gov (United States)

    Mahroof, R; Subramanyam, B

    2006-12-01

    Heating the ambient air of a whole, or a portion of a food-processing facility to 50 to 60 degrees C and maintaining these elevated temperatures for 24 to 36 h, is an old technology, referred to as heat treatment. There is renewed interest in adopting heat treatments around the world as a viable insect control alternative to fumigation with methyl bromide. There is limited published information on responses of the Indian meal moth, Plodia interpunctella (Hübner), exposed to elevated temperatures typically used during heat treatments. Time-mortality relationships were determined for eggs, fifth-instars (wandering-phase larvae), pupae, and adults of P. interpunctella exposed to five constant temperatures between 44 and 52 degrees C. Mortality of each stage increased with increasing temperature and exposure time. In general, fifth-instars were the most heat-tolerant stage at all temperatures tested. Exposure for a minimum of 34 min at 50 degrees C was required to kill 99% of the fifth-instars. It is proposed that heat treatments aimed at controlling fifth-instars should be able to control all other stages of P. interpunctella.

  2. Heat treatment effect on the properties of the EhP767 maraging steel welded joints

    International Nuclear Information System (INIS)

    Taver, E.I.; Piskarev, M.N.; Yushchenko, K.A.; Pustovit, A.I.; Anisimova, M.S.

    1977-01-01

    Heat treatment effect on properties of welded joints of maraging 03Kh13N4K13M3T (EhP767) steel with yield strength over 150 kgs/mm 2 has been investigated. It is shown, that change in impact strength of aged joints at - 196 deg C depends on the amount of residual austenite and grain size. To stabilize 20-40 % residual austenite heat treatment regimes have been developed. Recommended are quenching at 1030-1050 deg C, sub-zero treatment and aging at 520 deg C for 16 hrs

  3. Influence of Heat Treatment on Abrasive Wear Resistance of Silumin Matrix Composite Castings

    Directory of Open Access Journals (Sweden)

    Gawdzińska K.

    2016-03-01

    Full Text Available The authors attempted at examining the effect of heat treatment on abrasive wear resistance of metal composite castings. Metal matrix composites were made by infiltrating preforms created from unordered short fibers (graphite or silumin with liquid aluminium alloy AlSi12(b. Thus prepared composites were subject to solution heat treatment at a temperature of 520°C for four hours, then aging at a temperature of 220°C for four hours. Abrasion resistance of the material was tested before and after thermal treatment.

  4. SiO2 sol-gel films after ammonia and heat two-step treatments

    International Nuclear Information System (INIS)

    Zhang Chunlai; Wang Biyi; Tian Dongbin; Yin Wei; Jiang Xiaodong; Yuan Xiaodong; Yan Lianghong; Zhang Hongliang; Zhao Songnan; Lv Haibing

    2008-01-01

    SiO 2 thin films were deposited using tetraethoxylsilane as precursor, ammonia as catalyst on K9 glass by sol-gel method. These films were post-treated by ammonia and heat. The properties of the coatings were characterized by ellipsometer, UV-vis spectrophotometry, FTIR-spectroscopy, scanning probe microscope and contact angle measurement apparatus. The resuits indicate that the thickness of the films with ammonia and heat treatment tend to decrease. Both the refractive index and water contact angle increase after ammonia treatment. However, they both decrease after heat treatment. The former increases by 0.236 for the first step, then decreases by 0.202 for the second. The latter increases to 58.92 degree, then decreases to 38.07 degree. The transmittance of the coatings turn to be better and continuously shift to short wave by UV-vis spectrophotometry. The surface becomes smoother by AFM after the two-step treatment. (authors)

  5. Effect of heat treatment at 600 degree C for 10 hours on human BMP

    International Nuclear Information System (INIS)

    Izawa, H.; Hachiya, Y.; Muramatsu, K.; Narita, Y.; Kawai, T.

    1999-01-01

    Viral infection are an extremely serious in allogeneic bone transplantations. While it is essential to kill viruses such as HIV in allogeneic bone graft, the osteoinductive activity must be preserved. Heat treatment of allogeneic bone graft at 60 degree C for 10 hours is effective in killing viruses such as HIV, but it is unclear to what extent the activity of human bone morphogenetic protein (hBMP) is preserved. In this experiment crude hBMP was extracted from both heated and non-heated human bones which were decalcified by the Urist method. Gelatin capsules containing 5mg of crude hBMP were transplanted into the thigh muscles of 5 week old mice. Human bone samples heated in a water bath at 60 degree C for 10 hours and non-heated samples were each transplanted into 5 mice. At 20 days after transplantation, the heterotopic bone formation was compared by evaluation of X-ray and histologicic analysis. X-rays showed heterotopic bone formation in both heated and non-heated samples. Further, histologic analysis showed that peripheral osteoid tissue had developed into laminar bone formation and interlaminar bone marrow was observed. Heterotopic bone formation was induced by crude hBMP from heated bones in a similar way to crude hBMP from non-heated bones observed in X-ray. There was no significant difference in histologic analysis. The crude hBMP, extracted from bones which were heat-treated at 60 degree C for 10 hours induced heterotopic bone formation similar to that in non-heated bone observed by X-ray and histologic analysis at 20 days after transplantation. This demostrates that the heat-treated bone preserved osteoinduction

  6. A Study on Infrared Local Heat Treatment for AA5083 to Improve Formability and Automotive Part Forming

    Science.gov (United States)

    Lee, Eun-Ho; Yang, Dong-Yol; Ko, SeJin

    2017-10-01

    Automotive industries are increasingly employing aluminum alloys for auto parts to reduce vehicle weight. However, the low formability of aluminum alloys has been an obstacle to their application. To resolve the formability problem, some studies involving heat treatments under laboratory conditions have been reported. However, for industrial applications, the heat treatment sequence, heating energy efficiency, and a commercial part test should be studied. This work shows an infrared (IR) local heat treatment, heating only small areas where the heat treatment is required, for an aluminum alloy to improve the formability with a reduction of heating energy. The experiment shows that the formability drastically increases when the aluminum alloy is heat treated between two forming stages, referred to as intermediate heat treatment. The microstructures of the test pieces are evaluated to identify the cause of the increase in the formability. For an industrial application, an aluminum tailgate, which cannot be manufactured without heat treatment, was successfully manufactured by the IR local heat treatment with a reduction of energy. A simulation was also conducted with a stress-based forming limit diagram, which is not affected by the strain path and heat treatment histories. The simulation gives a good prediction of the formability improvement.

  7. Manufacturing of tailored tubes with a process integrated heat treatment

    Science.gov (United States)

    Hordych, Illia; Boiarkin, Viacheslav; Rodman, Dmytro; Nürnberger, Florian

    2017-10-01

    The usage of work-pieces with tailored properties allows for reducing costs and materials. One example are tailored tubes that can be used as end parts e.g. in the automotive industry or in domestic applications as well as semi-finished products for subsequent controlled deformation processes. An innovative technology to manufacture tubes is roll forming with a subsequent inductive heating and adapted quenching to obtain tailored properties in the longitudinal direction. This processing offers a great potential for the production of tubes with a wide range of properties, although this novel approach still requires a suited process design. Based on experimental data, a process simulation is being developed. The simulation shall be suitable for a virtual design of the tubes and allows for gaining a deeper understanding of the required processing. The model proposed shall predict microstructural and mechanical tube properties by considering process parameters, different geometries, batch-related influences etc. A validation is carried out using experimental data of tubes manufactured from various steel grades.

  8. Effect of acoustic softening on the thermal-mechanical process of ultrasonic welding.

    Science.gov (United States)

    Chen, Kunkun; Zhang, Yansong; Wang, Hongze

    2017-03-01

    Application of ultrasonic energy can reduce the static stress necessary for plastic deformation of metallic materials to reduce forming load and energy, namely acoustic softening effect (ASE). Ultrasonic welding (USW) is a rapid joining process utilizing ultrasonic energy to form a solid state joint between two or more pieces of metals. Quantitative characterization of ASE and its influence on specimen deformation and heat generation is essential to clarify the thermal-mechanical process of ultrasonic welding. In the present work, experiments were set up to found out mechanical behavior of copper and aluminum under combined effect of compression force and ultrasonic energy. Constitutive model was proposed and numerical implemented in finite element model of ultrasonic welding. Thermal-mechanical analysis was put forward to explore the effect of ultrasonic energy on the welding process quantitatively. Conclusions can be drawn that ASE increases structural deformation significantly, which is beneficial for joint formation. Meanwhile, heat generation from both frictional work and plastic deformation is slightly influenced by ASE. Based on the proposed model, relationship between ultrasonic energy and thermal-mechanical behavior of structure during ultrasonic welding was constructed. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. THE INFLUENCE OF PRE-HEAT TREATMENT ON WHITE CAST IRONS PLASTICITY

    Directory of Open Access Journals (Sweden)

    T. M. Myronova

    2013-11-01

    Full Text Available Purpose. The development of heat treatment modes of white cast irons for structure changes in their eutectic constituent, namely in disturbing the monolithic structure of ledeburite colonies cementite structure and eutectic net continuity. Also the mentioned heat treatment modes are targeted to the eutectic net shift for the most suitable position from the point of plastic deforming. Methodology. The hypoeutectic white cast irons with 2.92…3.35 % carbon content and additionally alloyed by 3.18 % vanadium have been used as the research materials. The mentioned alloys have been pre-heat treated and hot twist tested. Findings. The research results showed that the carbide net breaking by plastic deforming leads to cast irons mechanical properties increasing but has difficulties in implementation due to the white cast irons low plasticity. The influence of different pre-heat treatment modes on structure and plasticity of white hypoeutectic cast irons have been investigated. They include the isotherm soaking under the different temperatures as well as multiply soakings and thermo-cycling. The influence of eutectic level, as well as pre heat treatment modes on different composition white cast irons hot plasticity have been investigated. Originality. It was determined that the heat treatment, which leads to double α→γ recrystallization under 860 – 950 °С and reperlitization under 720-680 °С results in significant increase of plasticity, as well as in un-alloyed and alloyed by vanadium white cast irons. It takes place due to carbide matrix phase separation in ledeburite colonies by new phase boundaries forming especially due to carbide transformations under vanadium alloying. Practical value. The implementation of pre-heat treatment with phase recrystallization resulted in hypoeutectic white cast irons plasticity increasing. The obtained level of cast iron plasticity corresponds to the one of carbide class steels, which ensures the successful

  10. Improving the efficiency of plasma heat treatment of metals

    International Nuclear Information System (INIS)

    Gabdrakhmanov, Az T; Israphilov, I H; Galiakbarov, A T; Samigullin, A D; Gabdrakhmanov, Al T

    2016-01-01

    This paper proposes an effective way of the plasma hardening the surface layer at the expense combined influence of the plasma jet and a cold air flow. After that influence occurs a distinctive by plasma treatment microstructure with increased microhardness (an increase of 35%) and depth. There is proposed an improved design of the vortex tube for receiving the air flow with a temperature of 20 C to - 120C. (paper)

  11. Modification of the original color of the Eucalyptus grandis wood by heat treatments

    Directory of Open Access Journals (Sweden)

    Rosilei Aparecida Garcia

    2014-09-01

    Full Text Available The objective of this study was to determine the modification of original color of Eucalyptus grandis Hill ex. Maiden wood after heat-treatment. Wood samples were heat-treated under different temperatures (180, 200, 215 and 230ºC and time conditions (15 minutes, 2 and 4 hours. Color analysis were performed on the CIE L*a*b* system by using a Color Eye XTH-X-Rite 200d spectrophotometer. All heat treatments promoted an alteration of the original color of wood. Heat-treated woods presented lower L* (lightness values than untreated wood (control, characterizing the wood darkness, mainly for more severe conditions of temperature and time. Chromatic coordinates (a* and b* showed different behaviors depending on the temperature-time combination. The modification of the original color of the wood allowed the creation of new color patterns, which can add greater value to the studied wood.

  12. The effect of heat treatment on phosphorus segregation in a submerged-arc weld metal

    International Nuclear Information System (INIS)

    Beere, W.B.; Buswell, J.T.

    1999-01-01

    Intergranular fracture (IGF) has been observed in carbon-manganese steels after irradiation or high temperature exposure for prolonged periods. The effect is associated with an increase in the ductile-brittle transition temperature and has been related to phosphorus diffusion to grain boundaries. Phosphorus also diffuses thermally at the temperatures used for post-weld heat treatments such that in principle, the slightly different heat treatments given to different parts of a large vessel could lead to differing grain boundary phosphorus coverage and hence susceptibility to IGF. The effect of typical heat treatments on phosphorus coverage has been investigated using a finite difference model based on a theory that has been fitted to a wide range of constant temperature data. Regardless of previous history, the grain boundary coverage of phosphorus was predicted to depend on the final anneal and cooling rate. These differed insufficiently in the typical heat treatments to produce significant differences in segregation. It was concluded that the ductile-brittle transition temperature in submerged-arc welds would be unaffected in vessels that had seen typical post-weld heat treatments

  13. Effect of Cold Drawing and Heat Treatment on the Microstructure of Invar36 Alloy Wire

    International Nuclear Information System (INIS)

    Han, Seung Youb; Jang, Seon Ah; Eun, Hee-Chul; Choi, Jung-Hoon; Lee, Ki Rak; Park, Hwan Seo; Ahn, Do-Hee; Kim, Soo Young; Kim, Jea Youl; Shin, Sang Yong

    2016-01-01

    In this study, the effect of cold drawing and heat treatment on the microstructure of Invar36 alloy wire was investigated. Invar36 alloy wire is used as a transmission line core material, and is required to have high strength. The diameter of the Invar36 alloy wire specimens were reduced from 16 mm to 4.3 mm after three cold drawing and two heat treatment processes, thereby increasing tensile strength. Specimens were taken after each of the cold drawing and heat treatment processes, and their microstructure and tensile properties were analyzed. The Invar36 alloy wire had a γ-(Fe, Ni) phase matrix before the cold drawing and heat treatment processes. After the cold drawing processes, {220} and {200} textures were mainly achieved. After the heat treatment processes, a {200} recrystallization γ-(Fe, Ni) phase was formed with fine carbides. The recrystallization γ-(Fe, Ni) phase grains had low dislocation density, so they probably accommodated a large amount of deformation during the cold drawing processes.

  14. Heat treatment of the EN AC-AlSi9Cu3(Fe alloy

    Directory of Open Access Journals (Sweden)

    J. Pezda

    2010-04-01

    Full Text Available Silumins are widely used in automotive, aviation and shipbuilding industries; as having specific gravity nearly three times lower than specific gravity of cast iron the silumins can be characterized by high mechanical properties. Additionally, they feature good casting properties, good machinability and good thermal conductivity. i.e. properties as required for machinery components operating in high temperatures and at considerable loads. Mechanical properties of the silumins can be upgraded, implementing suitably selected heat treatment. In the paper is presented an effect of modification and heat treatment processes on mechanical properties of the EN AC-AlSi9Cu3(Fe alloy. Investigated alloy has undergone typical processes of modification and refining, and next heat treatment. Temperature range of the heat treatment operations was determined on base of curves from the ATD method. Obtained results concern registered melting and solidification curves from the ATD method and strength tests. On base of the performed tests one has determined range of the heat treatment parameters which would assure obtainment of the best possible mechanical properties of the EN AC-AlSi9Cu3(Fe alloy.

  15. Effect of heat treatments on machinability of gold alloy with age-hardenability at intraoral temperature.

    Science.gov (United States)

    Watanabe, I; Baba, N; Watanabe, E; Atsuta, M; Okabe, T

    2004-01-01

    This study investigated the effect of heat treatment on the machinability of heat-treated cast gold alloy with age-hardenability at intraoral temperature using a handpiece engine with SiC wheels and an air-turbine handpiece with carbide burs and diamond points. Cast gold alloy specimens underwent various heat treatments [As-cast (AC); Solution treatment (ST); High-temperature aging (HA), Intraoral aging (IA)] before machinability testing. The machinability test was conducted at a constant machining force of 0.784N. The three circumferential speeds used for the handpiece engine were 500, 1,000 and 1,500 m/min. The machinability index (M-index) was determined as the amount of metal removed by machining (volume loss, mm(3)). The results were analyzed by ANOVA and Scheffé's test. When an air-turbine handpiece was used, there was no difference in the M-index of the gold alloy among the heat treatments. The air-turbine carbide burs showed significantly (pmachinability of the gold alloy using the air-turbine handpiece. The heat treatments had a small effect on the M-index of the gold alloy machined with a SiC wheel for a handpiece engine.

  16. Effect of Cold Drawing and Heat Treatment on the Microstructure of Invar36 Alloy Wire

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Youb; Jang, Seon Ah; Eun, Hee-Chul; Choi, Jung-Hoon; Lee, Ki Rak; Park, Hwan Seo; Ahn, Do-Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Soo Young; Kim, Jea Youl [RandD Center, KOS Ltd., Yangsan (Korea, Republic of); Shin, Sang Yong [University of Ulsan, Ulsan (Korea, Republic of)

    2016-10-15

    In this study, the effect of cold drawing and heat treatment on the microstructure of Invar36 alloy wire was investigated. Invar36 alloy wire is used as a transmission line core material, and is required to have high strength. The diameter of the Invar36 alloy wire specimens were reduced from 16 mm to 4.3 mm after three cold drawing and two heat treatment processes, thereby increasing tensile strength. Specimens were taken after each of the cold drawing and heat treatment processes, and their microstructure and tensile properties were analyzed. The Invar36 alloy wire had a γ-(Fe, Ni) phase matrix before the cold drawing and heat treatment processes. After the cold drawing processes, {220} and {200} textures were mainly achieved. After the heat treatment processes, a {200} recrystallization γ-(Fe, Ni) phase was formed with fine carbides. The recrystallization γ-(Fe, Ni) phase grains had low dislocation density, so they probably accommodated a large amount of deformation during the cold drawing processes.

  17. Study of the Al-Si-X system by different cooling rates and heat treatment

    Directory of Open Access Journals (Sweden)

    Miguel Angel Suarez

    2012-10-01

    Full Text Available The solidification behavior of the Al-12.6% Si (A1, the hypereutectic Al-20%Si (A2 and the Al-20%Si-1.5% Fe-0.5%Mn (A3 (in wt. (% alloys, at different cooling rates is reported and discussed. The cooling rates ranged between 0.93 °C/s and 190 °C/s when cast in sand and copper wedge-shaped molds, respectively. A spheroidization heat treatment was carried out to the alloys in the as-cast condition at 540 °C for 11 hours and quench in water with a subsequent heat treatment at 170 °C for 5 hours with the purpose of improving the mechanical properties. The samples were characterized by optical microscopy, scanning electron microscopy and mechanically by tensile test, in order to evaluate the response of the heat treatment on the different starting microstructures and mechanical properties. It was found that alloys cooled at rates greater than 10.8 °C/s had a smaller particle size and better distribution, also showed a greater response to spheroidization heat treatment of all silicon (Si phases. The spheroidization heat treatment caused an increase in the ultimate tensile stress (UTS and elongation when compared with the alloys in the as-cast condition. The highest UTS value of 174 MPa was obtained for the (A1 alloy.

  18. Impact of Surface Potential on Apatite Formation in Ti Alloys Subjected to Acid and Heat Treatments.

    Science.gov (United States)

    Yamaguchi, Seiji; Hashimoto, Hideki; Nakai, Ryusuke; Takadama, Hiroaki

    2017-09-24

    Titanium metal (Ti) and its alloys are widely used in orthopedic and dental fields. We have previously shown that acid and heat treatment was effective to introduce bone bonding, osteoconduction and osteoinduction on pure Ti. In the present study, acid and heat treatment with or without initial NaOH treatment was performed on typical Ti-based alloys used in orthopedic and dental fields. Dynamic movements of alloying elements were developed, which depended on the kind of treatment and type of alloy. It was found that the simple acid and heat treatment enriched/remained the alloying elements on Ti-6Al-4V, Ti-15Mo-5Zr-3Al and Ti-15Zr-4Nb-4Ta, resulting in neutral surface charges. Thus, the treated alloys did not form apatite in a simulated body fluid (SBF) within 3 days. In contrast, when the alloys were subjected to a NaOH treatment prior to an acid and heat treatment, alloying elements were selectively removed from the alloy surfaces. As a result, the treated alloys became positively charged, and formed apatite in SBF within 3 days. Thus, the treated alloys would be useful in orthopedic and dental fields since they form apatite even in a living body and bond to bone.

  19. The long-term effects of a life-prolonging heat treatment on the Drosophila melanogaster transcriptome suggest that heat shock proteins extend lifespan

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Sørensen, Peter; Loeschcke, Volker

    2014-01-01

    Heat-induced hormesis, i.e. the beneficial effect of mild heat-induced stress, increases the average lifespan of many organisms. This effect, which depends on the heat shock factor, decreases the log mortality rate weeks after the stress has ceased. To identify candidate genes that mediate......-treated flies. Several hsp70 probe sets were up-regulated 1.7–2-fold in the mildly stressed flies weeks after the last heat treatment (P shock protein, Hsp70, is reported to return to normal levels of expression shortly after heat stress. We...... conclude that the heat shock response, and Hsp70 in particular, may be central to the heat-induced increase in the average lifespan in flies that are exposed to mild heat stress early in life....

  20. Preliminary study on the forgeability and heat treatment response of niobium - containing tool steels materials

    International Nuclear Information System (INIS)

    Cescon, T.; Papaleo, R.

    1981-01-01

    The forgeability and microstructure of tool steels materials based on the M-2 composition, where W and V were partially replaced by Nb, were examined. The optimum heat-treating conditions were established. The poor response to heat treatment of some of the alloys studied indicated the need of increasing the C content of the steels when Nb is used as a substitute for W and V. (Author) [pt

  1. The effects of heat treatment and environment on corrosion fatigue

    International Nuclear Information System (INIS)

    Ballinger, R.G.; Hwang, I.S.; Elliott, C.K.

    1993-05-01

    Alloy X-750 is a nickel-base alloy used extensively in Light Water Reactor (LWR) nuclear power systems due to its excellent corrosion resistance and high temperature strength. In spite of alloy X-750's exceptional high temperature properties, it has been found to be susceptible to environmentally assisted fatigue and stress corrosion cracking in relatively low temperature aqueous environments such as those that exist in LWR systems. In order to develop a better understanding of the role that microstructure plays in the fatigue behavior of alloy X-750, three thermal treatments were studied. The treatments used were as hot worked + : (1) 24 h at 885 degree C + 20 h at 704 degree C (AH), (2) lh at 982 degree C + 20 h at 704 degree C (BH), and (3) 1 h at 1093 degree C + 20 h at 704 degree C (HTH). Fatigue crack growth tests were conducted at frequencies of 0.1 and 10 Hz in the following aqueous environments: (1) high purity, air saturated water (8 ppM O 2 ) at 93 degree C and 288 degree C, (2) high purity, deoxygenated water (5 ppb O 2 ) at 93 degree C, and (3) simulated BWR water chemistry with hydrogen additions at 288 degree C. Crack growth rate data was collected at constant values of stress intensity factor range (ΔK). The results show that crack growth rates and morphology are a function of ΔK, frequency, thermal treatment and environment. Frequency effects were most significant for the AH material. Crack growth rates generally decrease, for a given value of ΔK, in the BH and HTH materials with the HTH material showing the lowest growth rate

  2. Chemical heat treatment of low alloyed maraging steels

    Energy Technology Data Exchange (ETDEWEB)

    Malinov, L S; Korotich, I K [Zhdanovskij Metallurgicheskij Inst. (Ukrainian SSR)

    1979-09-01

    The investigation concerned the nitriding, cementation, chromizing, borating of economically alloyed maraging grade 04Kh2N5MFYu steel. The investigated methods of chemothermal treatment were found to considerably increase the hardness of the surface layer of the maraging steel. The high tempering of the grade 04Kh2N5MFYu cemented and hardened steel was found to produce secondary hardening. On chromizing, the diffusion layer is an alloyed ferrite which strengthens because of the dispersion hardening on ageing. The formation of the plastic low-carbon martensite at relatively small cooling rates greatly decreases the tendency of the boride layer to cracking.

  3. Increased sustainability of softening by producing pure calcite pellets for reuse

    NARCIS (Netherlands)

    Hofs, B; Baars, ET; Palmen, LJ; Elings, JA; Kors, L.J.; Kramer, O.J.I.; Koppers, H; van der Hoek, J.P.

    2015-01-01

    About 50% of the drinking water in the Netherlands is centrally softened by the drinking water companies in a process known as pellet softening. In this process a base and seeding material are mixed in an upflow reactor, where subsequently CaCO3 precipitates on a seed core as pellets. The seeding

  4. Influence of heat treatment on the machinability and corrosion behavior of AZ91 Mg alloy

    Directory of Open Access Journals (Sweden)

    Swetha Chowdary V

    2018-03-01

    Full Text Available In the present study, AZ91 Mg alloy was heat treated at 410 °C for 6, 12 and 24 h to investigate the influence of heat treatment on machinability and corrosion behavior. The effect of soaking time on the amount and distribution of Mg17Al12 (β – phase was analyzed under the optical microscope. Microhardness measurements demonstrated the increased hardness with increased heat treatment soaking time, which can be attributed to the solid solution strengthening. The influence of super saturated α-grains on reducing the cutting force (Fz with respect to increased cutting speed was observed as prominent. The corrosion behavior of the heat treated specimens was studied by conducting electrochemical tests. Surprisingly, corrosion rate of heat treated samples was observed as increased compared with the base material. From the results, it is evident that the machinability of AZ91 Mg alloy can be improved by producing super saturated α-grains through heat treatment but at the cost of losing corrosion resistance. Keywords: AZ91 Mg alloy, Solid solution, Turning, Corrosion, Machinability

  5. Suppression of outgassing from spindt-type cold-cathode by heat treatment

    International Nuclear Information System (INIS)

    Miyo, Yasuhiko; Ogiwara, Norio; Saidoh, Masahiro; Hayashi, Naoki; Turuta, Kouichi.

    1995-01-01

    In Spindt type cold cathode electron source (hereafter, referred to as FEA), field emission is used for extracting electrons. It was made clear that the FEA is an excellent electron source that never causes gas release by heating peripheral parts. But the gas release form the FEA was confirmed though it was slight accompanying the extraction of current. This gas release becomes a problem when pressure measurement is carried out by using the FEA in ultrahigh or extremely high vacuum. If the gas release occurs by the effect of the heat generation at the tip of an emitter accompanying the extraction of electron current, it is possible to reduce the gas release by carrying out the heat treatment of the FEA was attempted, and as the result, it was elucidated that by the heat treatment at 400degC, the gas release form the FEA was able to be suppressed. However, a new problem that the insulation between gate and emitter deteriorated and broke during the extraction of current occurred. The experimental method and the results of the reduction of gas release by heat treatment and the observation of the broken FEA with a scanning electron microscope are reported. Also the problem that in the FEA which was heat-treated at 400degC, the current has decreased from 500 μA to 100 μA in about 100 hours occurred. As to these problems, it is necessary to continue the experiment further. (K.I.)

  6. Evaluation of the Sensitization of 316L Stainless Steels After the Post Weld Heat Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Junho; Jang, Changheui [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Kyoung Soo [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2014-05-15

    It was observed that the PWSCC growth rate of alloy 182 was markedly decreased after PWHT. However, the PWHT of components made of stainless steels (SSs) would be limited because of the concerns about sensitization when they are exposed to temperature range of 500 to 800 .deg. C. Also, the sensitization of austenitic stainless steels could increase the susceptibility to intergrannular stress corrosion cracking. Therefore, the effect of PWHT on the sensitization behaviors of 316L SSs having predominant austenitic structure with small amount of ferrite was investigated to assess the applicability of PWHT to dissimilar weld area with austenitic stainless steels. The sensitization behaviors of two heats of 316L SSs with small amount of ferrite were investigated after heat treatment at 600, 650 and 700 .deg. C. Grain boundary sensitization was not observed in 316L SSs after the heat treatment at 600, 650 and 700 .deg. C up to 30 h. The increase in degree of sensitization (DOS) was caused by reduction of corrosion resistance in ferrite phase due to formation of chromium carbide and intermatallic phases during heat treatment. The DOS value of 316L SSs depended on the ferrite morphology. The stringer type of ferrite (316L-heat A) showed relatively higher DOS in comparison with 316L containing blocky type of ferrite (316L-heat B). It could be due to sufficient supplement of chromium in larger size of ferrite phase.

  7. Evaluation of the Sensitization of 316L Stainless Steels After the Post Weld Heat Treatment

    International Nuclear Information System (INIS)

    Lee, Junho; Jang, Changheui; Lee, Kyoung Soo

    2014-01-01

    It was observed that the PWSCC growth rate of alloy 182 was markedly decreased after PWHT. However, the PWHT of components made of stainless steels (SSs) would be limited because of the concerns about sensitization when they are exposed to temperature range of 500 to 800 .deg. C. Also, the sensitization of austenitic stainless steels could increase the susceptibility to intergrannular stress corrosion cracking. Therefore, the effect of PWHT on the sensitization behaviors of 316L SSs having predominant austenitic structure with small amount of ferrite was investigated to assess the applicability of PWHT to dissimilar weld area with austenitic stainless steels. The sensitization behaviors of two heats of 316L SSs with small amount of ferrite were investigated after heat treatment at 600, 650 and 700 .deg. C. Grain boundary sensitization was not observed in 316L SSs after the heat treatment at 600, 650 and 700 .deg. C up to 30 h. The increase in degree of sensitization (DOS) was caused by reduction of corrosion resistance in ferrite phase due to formation of chromium carbide and intermatallic phases during heat treatment. The DOS value of 316L SSs depended on the ferrite morphology. The stringer type of ferrite (316L-heat A) showed relatively higher DOS in comparison with 316L containing blocky type of ferrite (316L-heat B). It could be due to sufficient supplement of chromium in larger size of ferrite phase

  8. Effect of the Heat Treatment on the Graphite Matrix of Fuel Element for HTGR

    International Nuclear Information System (INIS)

    Lee, Chungyong; Lee, Seungjae; Suh, Jungmin; Jo, Youngho; Lee, Youngwoo; Cho, Moonsung

    2013-01-01

    In this paper, the cylinder-formed fuel element for the block type reactor is focused on, which consists of the large part of graphite matrix. One of the most important properties of the graphite matrix is the mechanical strength for the high reliability because the graphite matrix should be enabled to protect the TRISO particles from the irradiation environment and the impact from the outside. In this study, the three kinds of candidate graphites and Phenol as a binder were chosen and mixed with each other, formed and heated for the compressive strength test. The objective of this research is to optimize the kinds and composition of the mixed graphite and the forming process by evaluating the compressive strength before/after heat treatment (carbonization of binder). In this study, the effect of heat treatment on graphite matrix was studied in terms of the density and the compressive strength. The size (diameter and length) of pellet is increased by heat treatment. Due to additional weight reduction and swelling (length and diameter) of samples the density of graphite pellet is decreased from about 2.0 to about 1.7g/cm 3 . From the mechanical test results, the compressive strength of graphite pellets was related to the various conditions such as the contents of binder, the kinds of graphite and the heat treatment. Both the green pellet and the heat treated pellet, the compressive strength of G+S+P pellets is relatively higher than that of R+S+P pellets. To optimize fuel element matrix, the effect of Phenol and other binders, graphite composition and the heat treatment on the mechanical properties will be deeply investigated for further study

  9. Effect of foam on temperature prediction and heat recovery potential from biological wastewater treatment.

    Science.gov (United States)

    Corbala-Robles, L; Volcke, E I P; Samijn, A; Ronsse, F; Pieters, J G

    2016-05-15

    Heat is an important resource in wastewater treatment plants (WWTPs) which can be recovered. A prerequisite to determine the theoretical heat recovery potential is an accurate heat balance model for temperature prediction. The insulating effect of foam present on the basin surface and its influence on temperature prediction were assessed in this study. Experiments were carried out to characterize the foam layer and its insulating properties. A refined dynamic temperature prediction model, taking into account the effect of foam, was set up. Simulation studies for a WWTP treating highly concentrated (manure) wastewater revealed that the foam layer had a significant effect on temperature prediction (3.8 ± 0.7 K over the year) and thus on the theoretical heat recovery potential (30% reduction when foam is not considered). Seasonal effects on the individual heat losses and heat gains were assessed. Additionally, the effects of the critical basin temperature above which heat is recovered, foam thickness, surface evaporation rate reduction and the non-absorbed solar radiation on the theoretical heat recovery potential were evaluated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Effect of heat treatment time on microstructure and electrical conductivity in LATP glass ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sonigra, Dhiren, E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in; Soman, Swati, E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in; Kulkarni, Ajit R., E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in [Dept. of Metallurgical Engineering and Materials Science, IIT Bombay, Mumbai-400076 (India)

    2014-04-24

    Glass-ceramic is prepared by heat treatment of melt quenched 14Li{sub 2}O−9Al{sub 2}O{sub 3}−38TiO{sub 2}−39P{sub 2}O{sub 5} glass in the vicinity of crystallization temperature. Growth of ceramic phase is controlled by tuning heat treatment time at fixed temperature. Ceramic phase was identified to be LiTi{sub 2}(PO{sub 4}){sub 3} from X Ray Diffraction analysis. Microstructural evolution of this phase with hold time was observed under high resolution Scanning Electron Microscope. DC conductivity is observed to increase by 4-5 orders of magnitude in this glass-ceramic compared to parent glass. However, formation of pores and cracks with very large heat treatment time seem to hinder further increase of conductivity.

  11. Thermoluminescence and cathodoluminescence studies of calcite and MgO: surface defects and heat treatment

    International Nuclear Information System (INIS)

    Goeksu, H.Y.; Brown, L.M.

    1988-01-01

    Some of the problems which preclude accurate thermoluminescence (TL) dating of geologically formed calcite stem from different sample pre-treatment procedures, such as grinding, drilling or pre-heating. It has long been known that grinding can introduce spurious TL in calcite, but there have been wide differences of opinion as to the magnitude of the influence and its importance. Therefore, various grinding and acid-washing procedures have been suggested to avoid spurious thermoluminescence. Various models have been developed to explain the mechanism. We have studied the changes in thermoluminescence (TL) and cathodoluminescence (CL) properties as well as in the spectral composition of the glow from calcite and MgO due to surface defects and heat treatment. It is found that both laboratory heat treatment and surface indents give rise to changes in TL efficiency. (author)

  12. Regenerative heat treatments for the extension of the creep life of the superalloy IN-738

    International Nuclear Information System (INIS)

    Stevens, R.A.; Flewitt, P.E.J.

    1979-01-01

    Uniaxial creep tests have been performed on the cast nickel-base superalloy IN-738 at 1023K and 1123K. Microstructural damage occurring during creep has been characterised using transmission electron microscopy of surface and extraction replicas. Considerable coarsening of the γ' precipitates occurs during creep causing a progressive loss of creep strength. Intermediate heat treatment of interrupted specimens regenerates a microstructure similar to the original, and on re-testing significant creep life extensions are observed. These heat treatments do not completely recover the creep life due to the development of grain boundary cavitation. Additional heat treatments were performed under a superimposed hydrostatic pressure of 138 MPa to remove these cavities. (orig.) [de

  13. Variation of Mechanical Properties of High RRR And Reactor Grade Niobium With Heat Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Ganapati Myneni; H. Umezawa

    2003-06-01

    Superconducting rf cavities used as accelerating structures in particle accelerators are made from high purity niobium with residual resistance ratios greater than 250. Reactor grade niobium is also used to make wave-guide and/or end group components for these accelerating structures. The major impurities in this type of niobium are interstitially dissolved gases such as hydrogen, nitrogen, and oxygen in addition to carbon. After fabricating the niobium accelerating structures, they are subjected to heat treatments for several hours in vacuum at temperatures of up to 900 C for degassing hydrogen or up to 1400 C for improving the thermal conductivity of niobium considerably. These heat treatments are affecting the mechanical properties of niobium drastically. In this paper the variation of the mechanical properties of high purity and reactor grade niobium with heat treatments in a vacuum of {approx} 10{sup -6} Torr and temperatures from 600 C to 1250 C for periods of 10 to 6 hours are presented.

  14. Effect of heat treatment on CO2 adsorption of KOH-activated graphite nanofibers.

    Science.gov (United States)

    Meng, Long-Yue; Park, Soo-Jin

    2010-12-15

    In this work, graphite nanofibers (GNFs) were successfully expanded intercalating KOH followed by heat treatment in the temperature range of 700-1000 °C. The aim was to improve the CO(2) adsorption capacity of the GNFs by increasing the porosity of GNFs. The effects of heat treatment on the pore structures of GNFs were investigated by N(2) full isotherms, XRD, SEM, and TEM. The CO(2) adsorption capacity was measured by CO(2) isothermal adsorption at 25 °C and 1 atm. From the results, it was found that the activation temperature had a major influence on CO(2) adsorption capacity and textural properties of GNFs. The specific surface area, total pore volume, and mesopore volume of the GNFs increased after heat treatment. The CO(2) adsorption isotherms showed that G-900 exhibited the best CO(2) adsorption capacity with 59.2 mg/g. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. Heat treatment of processing sludge of ornamental rocks: application as pozzolan in cement matrices

    Directory of Open Access Journals (Sweden)

    J.G. Uliana

    Full Text Available The sector of ornamental rocks produces significant volume of waste during the sawing of the blocks and demand to find ways to recycle, given its environmental impact. Considering the possibilities of use of industrial by-products as mineral admixtures, aiming at sustainable development in the construction industry, this paper aims to study the performance of the processing sludge of ornamental rocks and grinding after heat treatment, based on their potential application as partial substitute for cement. The residue was characterized, cast and milled to produce glassy material. Was analyzed the mechanical performance and pozzolanic activity with partial replacement of cement by waste in natural condition and after heat treatment in mortars for comparison. The results were promising, so it was possible to verify that after heat treatment, the treated waste is presented as a material with pozzolanic characteristics.

  16. Examination of the influence of heat treatment on the properties of Al-Si alloys

    Energy Technology Data Exchange (ETDEWEB)

    Vuksanovic, D.; Rakocevic, S. [Faculty of Metallurgy, Podgorica (RS); Markovic, S. [Faculty of Technology and Metallurgy, Belgrade (RS); Petrovic, T. [Institute ' Kirilo Savic' , Belgrade (RS); Kovacevic, K. [Institute for Ferrous Metallurgy (RS); Tripkovic, S. [H.K. Petar Drapsin, Mladenovac (RS)

    2007-08-15

    In this paper the influence of heat treatment on the structural and mechanical properties of Al-Si alloys was investigated. Silicon content in the examined alloys was in the range 11 to 14%, the contents of the other alloying elements were in the standard range but all alloys were modified with strontium. The regime of the applied heat treatment was quenching (520 C/6h - cooling in water) + aging (205oC/7h - air cooling). The examinations were carried out at room temperature as well as at 250 C and 300 C. The obtained results showed a positive influence of the applied heat treatment on the mechanical properties of the examined alloys. The improvement of the mechanical properties can be considered as a consequence of a redistribution and change of morphology of the phases present in the structure of the alloys. (orig.)

  17. Shelf-life extension of bread by heat and irradiation treatment [Bangladesh

    International Nuclear Information System (INIS)

    Begum, F.; Siddique, A.K.; Choudhury, N.; Mollah, R.A.

    1994-01-01

    Bread slices were given irradiation treatment 0.5, 1.0, 1.5, and 2.0 KGy and heat treatment at 60 deg. C for 20 min to control mould growth. Mould growth was reladed at ambient temperature by 3, 4, 6 and 8 days after 0.5, 1.0, 1.5 and 2.0 KGy treatments, respectively, compared to 2 days in case of control sample and 3 days for heat treatment alone. Combination of heat with irradiation at 0.5, 1.0, 1.5 and 2.0 KGy retarded mould growth up to 4, 6, 7 an 9 days, respectively. Organoleptically, the irradiated bread slices were acceptable up to 3 to 6 days depending on the treatment. The combination method treated slices were acceptable up to 8 days. The application of radiation dose exceeding 2.0 KGy caused off flavour. Mild heat treatment and radiation in combination resulted in a synergistic antifungal effect and enhanced shelf-life of bread

  18. Improvement of stress-rupture life of GTD-111 by second solution heat treatment

    International Nuclear Information System (INIS)

    Yang, Caixiong; Xu, Yulai; Zhang, Zixing; Nie, Heng; Xiao, Xueshan; Jia, Guoqing; Shen, Zhi

    2013-01-01

    Highlights: ► The second solution heat treatment promoted the solution of γ–γ′ eutectic into γ matrix. ► The volume fraction of γ′ increases significantly after adding the second solution heat treatment. ► The improved stress-rupture life is primarily due to the increased volume fraction of γ′ phase. -- Abstract: An added second solution heat treatment was conducted to investigate its effects on the microstructures and stress-rupture properties of GTD-111. The microstructures were analyzed by scanning electron microscope after each step of heat treatments. The stress-rupture life of GTD-111 dramatically increases from about 180 to 288 h at 871 °C/310 MPa after adding a second solution heat treatment. The added second solution heat treatment promoted the solution of γ–γ′ eutectic into γ matrix, and facilitated the nucleation and precipitate of the secondary γ′ particles. The distribution of γ′ phase becomes much denser, the width of γ matrix channel is also reduced, and the volume fraction of γ′ phase significantly increases from about 29.3% to 44.2%. The improved stress-rupture life is primarily due to the increased volume fraction of γ′ phase. The carbides mainly consist of MC and a small amount of M 23 C 6 , which may prevent the dislocation moving and/or grain boundary sliding, and further improve the stress-rupture properties of GTD-111.

  19. Heat treatment of a direct composite resin: influence on flexural strength

    Directory of Open Access Journals (Sweden)

    Caroline Lumi Miyazaki

    2009-09-01

    Full Text Available The purpose of this study was to evaluate the flexural strength of a direct composite, for indirect application, that received heat treatment, with or without investment. One indirect composite was used for comparison. For determination of the heat treatment temperature, thermogravimetric analysis (TGA and differential scanning calorimetry (DSC were performed, considering the initial weight loss temperature and glass transition temperature (Tg. Then, after photoactivation (600 mW/cm² - 40 s, the specimens (10 x 2 x 2 mm were heat-treated following these conditions: 170ºC for 5, 10 or 15 min, embedded or not embedded in investment. Flexural strength was assessed as a means to evaluate the influence of different heat treatment periods and investment embedding on mechanical properties. The data were analyzed by ANOVA and Tukey's test (α = 0.05. TGA showed an initial weight loss temperature of 180ºC and DSC showed a Tg value of 157°C. Heat treatment was conducted in an oven (Flli Manfredi, Italy, after 37°C storage for 48 h. Flexural strength was evaluated after 120 h at 37°C storage. The results showed that different periods and investment embedding presented similar statistical values. Nevertheless, the direct composite resin with treatments presented higher values (178.7 MPa compared to the indirect composite resin (146.0 MPa and the same direct composite submitted to photoactivation only (151.7 MPa. Within the limitations of this study, it could be concluded that the heat treatment increased the flexural strength of the direct composite studied, leading to higher mechanical strength compared to the indirect composite.

  20. Influence of heat treatment on the microstructure and mechanical properties of Alloy 718 base metal and weldments

    International Nuclear Information System (INIS)

    Mills, W.J.

    1979-06-01

    Effect of heat treatment on the metallurgical structure and tensile properties of three heats of Alloy 718 base metal and an Alloy 718 GTA weldment were characterized. Heat treatments employed were the conventional (ASTM A637) precipitation treatment and a modified precipitation treatment designed to improve the toughness of the weldments. The GTA weldments were characterized in the as-welded condition. Light microscopy, thin foil, and surface replica electron microscopy revealed that the microstructure of this superalloy was sensitive to heat treatment and heat-to-heat variations. The modified aging treatment resulted in a larger grain size and a more homogeneous microstructure than the conventional treatments. The morphology of the primary strengthening γ phase was found to be finer and more closely spaced in the conventionally treated condition. Room and elevated temperature tensile testing revealed that the strength of the conventionally treated alloy was generally superior to that of the modified material. The conventional aging treatment resulted in greater heat-to-heat variations in tensile properties. This behavior was correlated with variations in the microstructure resulting from the precipitation heat treatments. The precipitate morphology of the GTA weldments was sensitive to heat treatment. The Laves phase was present in the interdendritic regions of both heat-treated welds. The modified aging treatment reduced the amount of Laves phase present in the weld zone. Room and elevated temperature tensile properties of the precipitation hardened weldments were relatively insensitive to heat treatment, suggesting that reduction in Laves phase from the weld zone had essentially no effect on tensile properties. As-welded GTA weldments exhibited lower strength levels and higher ductility values than heat-treated welds

  1. Effect of heat treatment on the grooving corrosion resistance of ERW pipes

    International Nuclear Information System (INIS)

    Lee, Jong Kwon; Lee, Jae Young; Lim, Soo Hyun; Park, Ji Hwan; Seo, Bo Min; Kim, Seon Hwa

    2002-01-01

    The v-sharp grooving corrosion of ERW(electrical resistance welding) steel pipes limited their wide application in the industry in spite of their high productivity and efficiency. The grooving corrosion is caused mainly by the different microstructures between the matrix and weld that is formed during the rapid heating and cooling cycle in welding. By this localized corrosion reaction of pipes, it evolves economic problems such as the early damage of industrial facilities and pipe lines of apartment, and water pollution. Even though the diminishing of sulfur content is most effective to decrease the susceptibility of grooving corrosion, it requires costly process. In this study, improvement of grooving corrosion resistance was pursuited by post weld heat treatment in the temperature range between 650 .deg. C and 950 .deg. C. Also, the effect of heat input in the welding was investigated. By employing chromnoamperometry and potentiodynamic experiment, the corrosion rate and grooving corrosion index(α) were obtained. It was found that heat treatment could improve the grooving corrosion resistance. Among them, the heat treated at 900 .deg. C and 950 .deg. C had excellent grooving corrosion resistance. The index of heat treated specimen at 900 .deg. C and 950 .deg. C were 1.0, 1.2, respectively, which are almost immune to the grooving corrosion. Potential difference after the heat treatment, between base and weld metal was decreased considerably. While the as-received one measured 61∼71 mV, that of the 900 .deg. C heat treated steel pipe measured only 10mV. The results were explained and discussed

  2. Improving the conductivity of single-walled carbon nanotubes films by heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jiaping [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Sun Jing, E-mail: jingsun@mail.sic.ac.c [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Gao Lian, E-mail: liangaoc@online.sh.c [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Liu Yangqiao; Wang Yan; Zhang Jing [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Kajiura, Hisashi; Li Yongming; Noda, Kazuhiro [Advanced Materials Laboratories, Sony Corporation, Atsugi Tec. No. 2, 4-16-1 Okata Atsugi, Kanagawa 243-0021 (Japan)

    2009-10-19

    A simple heat treatment method was applied to remove surfactants remaining in the single-walled carbon nanotubes (SWNTs) films at 300 deg. C for 5 h in air. Scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and reflected light interference microscope (RLIM) were employed to verify the elimination of surfactants. The comprehensive performance, especially the conductivity, could be improved by more than one order after heat treatment. For example, using SDBS as dispersant, the sheet resistance decreased from 782,600 OMEGA/square to 40,460 OMEGA/square with the transmittance of about 99.5% at 550 nm.

  3. 99Mo production using MoO3 pellets obtained by mechanical compression and heat treatment

    International Nuclear Information System (INIS)

    Rojas, Jorge; Mendoza, Pablo; Lopez, Alcides

    2014-01-01

    This paper shows the results of the MoO 3 pellets fabrication by mechanical compression and the heat treatment method (MCHT) in order to optimize the production of 99 Mo in the RACSO Nuclear Center. The effects of polyvinyl alcohol (PVA) as binder are assessed by heat treatment of pellets in air atmosphere, evaluating the elimination process with increasing temperature and solubility in 5N NaOH. The results show that the pellets fabrication technique is suitable because fulfills the required technical specifications, allows to irradiate 50 % more of 98 Mo mass and facilitate a safer radiological handling of the irradiated MoO 3 . (authors).

  4. Artificial crystals with 3d metal and palladium particles subjected to high-temperature heat treatment

    Science.gov (United States)

    Rinkevich, A. B.; Nemytova, O. V.; Perov, D. V.; Samoylovich, M. I.; Kuznetsov, E. A.

    2018-04-01

    High-temperature heat treatment has valuable impact on the structure and physical properties of artificial crystals with 3d metal and palladium particles. Artificial crystals are obtained by means of introduction of particles into the interspherical voids of opal matrices. The magnetic properties are studied at the temperatures ranging from 2 to 300 K and in fields up to 350 kOe. Microwave properties are investigated in the millimeter frequency range. The complex dielectric permittivity of several nanocomposites is measured. The influence of heat treatment up to 960 °C on the structure of artificial crystals is clarified.

  5. Universal high-temperature heat treatment furnace for FBR mixed uranium and plutonium carbide fuel

    International Nuclear Information System (INIS)

    Handa, Muneo; Takahashi, Ichiro; Watanabe, Hitoshi

    1978-10-01

    A universal high-temperature heat treatment furnace for LMFBR advanced fuels was installed in Plutonium Fuel Laboratory, Oarai Research Establishment. Design, construction and performance of the apparatus are described. With the apparatus, heat treatment of the fuel under a controlled gas atmosphere and quenching of the fuel with blowing helium gas are possible. Equipment to measure impurity gas release of the fuel is also provided. Various plutonium enclosure techniques, e.g., a gas line filter with new exchange mechanics, have been developed. In performance test, results of the enclosure techniques are described. (author)

  6. A heat mathematical model of polymer composite cylinder during microwave treatment

    Directory of Open Access Journals (Sweden)

    S. V. Reznik

    2014-01-01

    Full Text Available Traditional technologies of producing epoxy based polymer composite materials (PCM require a long-term and energy consuming thermal processing. Microwave heating could be used as an alternative technology for heating work pieces made of PCM; this would allow to reduce treatment time and energy consumption significantly. A mathematical model of temperature distribution inside a cylindrical composite system during microwave treatment was investigated in this paper. The model includes a hollow PCM cylinder made of an epoxy binder and carbon fibers and a solid cylindrical mandrel. Theoretical and experimental results on the temperature state of the system were analyzed and discussed.

  7. Study on mechanical properties of the laminated composite materials with compatible heat treatments

    International Nuclear Information System (INIS)

    Pashkov, P.O.; Pektemirov, B.G.; Yaroshenko, A.P.

    1980-01-01

    Considered is the behaviour during axial extension of trilament composite materials, the mechanical properties of which are formed mainly by heat treatment. Application in the composite of the materials with compatible heat treatment is most rational. It is shown that for (ATsMg+N18K8M5T+ATsMg), (KhN78+VKS+KhH78) composites, the constituents of which are relatively plastic and tightly bound with each other, the tensile strength and uniform strain are changed additively

  8. Technoeconomic Optimization of Waste Heat Driven Forward Osmosis for Flue Gas Desulfurization Wastewater Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gingerich, Daniel B [Carnegie Mellon Univ., Pittsburgh, PA (United States); Bartholomew, Timothy V [Carnegie Mellon Univ., Pittsburgh, PA (United States); Mauter, Meagan S [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-06-26

    With the Environmental Protection Agency’s recent Effluent Limitation Guidelines for Steam Electric Generators, power plants are having to install and operate new wastewater technologies. Many plants are evaluating desalination technologies as possible compliance options. However, the desalination technologies under review that can reduce wastewater volume or treat to a zero-liquid discharges standard have a significant energy penalty to the plant. Waste heat, available from the exhaust gas or cooling water from coal-fired power plants, offers an opportunity to drive wastewater treatment using thermal desalination technologies. One such technology is forward osmosis (FO). Forward osmosis utilizes an osmotic pressure gradient to passively pull water from a saline or wastewater stream across a semi-permeable membrane and into a more concentrated draw solution. This diluted draw solution is then fed into a distillation column, where the addition of low temperature waste heat can drive the separation to produce a reconcentrated draw solution and treated water for internal plant reuse. The use of low-temperature waste heat decouples water treatment from electricity production and eliminates the link between reducing water pollution and increasing air emissions from auxiliary electricity generation. In order to evaluate the feasibility of waste heat driven FO, we first build a model of an FO system for flue gas desulfurization (FGD) wastewater treatment at coal-fired power plants. This model includes the FO membrane module, the distillation column for draw solution recovery, and waste heat recovery from the exhaust gas. We then add a costing model to account for capital and operating costs of the forward osmosis system. We use this techno-economic model to optimize waste heat driven FO for the treatment of FGD wastewater. We apply this model to three case studies: the National Energy Technology Laboratory (NETL) 550 MW model coal fired power plant without carbon

  9. Physical aspects of thermotherapy: A study of heat transport with a view to treatment optimisation

    Science.gov (United States)

    Olsrud, Johan Karl Otto

    1998-12-01

    Local treatment with the aim to destruct tissue by heating (thermotherapy) may in some cases be an alternative or complement to surgical methods, and has gained increased interest during the last decade. The major advantage of these, often minimally-invasive methods, is that the disease can be controlled with reduced treatment trauma and complications. The extent of thermal damage is a complex function of the physical properties of tissue, which influence the temperature distribution, and of the biological response to heat. In this thesis, methods of obtaining a well-controlled treatment have been studied from a physical point of view, with emphasis on interstitial laser-induced heating of tumours in the liver and intracavitary heating as a treatment for menorrhagia. Hepatic inflow occlusion, in combination with temperature-feedback control of the output power of the laser, resulted in well defined damaged volumes during interstitial laser thermotherapy in normal porcine liver. In addition, phantom experiments showed that the use of multiple diffusing laser fibres allows heating of clinically relevant tissue volumes in a single session. Methods for numerical simulation of heat transport were used to calculate the temperature distribution and the results agreed well with experiments. It was also found from numerical simulation that the influence of light transport on the damaged volume may be negligible in interstitial laser thermotherapy in human liver. Finite element analysis, disregarding light transport, was therefore proposed as a suitable method for 3D treatment planning. Finite element simulation was also used to model intracavitary heating of the uterus, with the purpose of providing an increased understanding of the influence of various treatment parameters on blood flow and on the depth of tissue damage. The thermal conductivity of human uterine tissue, which was used in these simulations, was measured. Furthermore, magnetic resonance imaging (MRI) was

  10. EFFECT OF PRE-HEAT TREATMENT ON MECHANICAL PROPERTIES OF Ti-6Al-4V WELDS

    Directory of Open Access Journals (Sweden)

    Gnofam Jacques TCHEIN

    2016-11-01

    Full Text Available The work presented here is related to the optimization of the Friction Stir Welding (FSW process. The objective is to study the influence of some parameters used in the production of welded joints by FSW. The most important parameters are the welding speed and the rotational speed of the tool. The effect of pre-heat treatment on the plates to be welded is also studied by the design of experimental methods. These pre-heat treatments result not only in a change of mechanical properties of plates to be welded, but also of their microstructure. The experiments were performed following a 16 lines fractional Taguchi table.

  11. Effect of heat treatment duration on tribological behavior of electroless Ni-(high)P coatings

    Science.gov (United States)

    Biswas, A.; Das, S. K.; Sahoo, P.

    2016-09-01

    Electroless nickel coating occurs through an autocatalytic chemical reaction and without the aid of electricity. From tribological perspective, it is recommended due to its high hardness, wear resistance, lubricity and corrosion resistance properties. In this paper electroless Ni-P coatings with high phosphorous weight percentages are developed on mild steel (AISI 1040) substrates. The coatings are subjected to heat treatment at 300°C and 500°C for time durations up to 4 hours. The effect of heat treatment duration on the hardness as well as tribological properties is discussed in detail. Hardness is measured in a micro hardness tester while the tribological tests are carried out on a pin-on-disc tribotester. Wear is reported in the form of wear rates of the sample subjected to the test. As expected, heat treatment of electroless Ni-P coating results in enhancement in its hardness which in turn increases its wear resistance. The present study also finds that duration of heat treatment has quite an effect on the properties of the coating. Increase in heat treatment time in general results in increase in the hardness of the coating. Coefficient of friction is also found to be lesser for the samples heat treated for longer durations (4 hour). However, in case of wear, similar trend is not observed. Instead samples heat treated for 2 to 3 hour display better wear resistance compared to the same heat treated for 4 hour duration. The microstructure of the coating is also carried out to ensure about its proper development. From scanning electron microscopy (SEM), the coating is found to possess the conventional nodular structure while energy dispersive X-ray analysis (EDX) shows that the phosphorous content in the coating to be greater than 9%. This means that the current coating belongs to the high phosphorous category. From X-ray diffraction analysis (XRD), it is found that coating is amorphous in as-deposited condition but transforms into a crystalline structure with

  12. Effect of Heat Treatment Parameters on the Microstructure and Properties of Inconel-625 Superalloy

    Science.gov (United States)

    Sukumaran, Arjun; Gupta, R. K.; Anil Kumar, V.

    2017-07-01

    Inconel-625 is a solid solution-strengthened alloy used for long-duration applications at high temperatures and moderate stresses. Different heat treatment cycles (temperatures of 625-1025 °C and time of 2-6 h) have been studied to obtain optimum mechanical properties suitable for a specific application. It has been observed that room temperature strength and, hardness decreased and ductility increased with increase in heat treatment temperature. The rate of change of these properties is found to be moderate for the samples heat-treated up to 850 °C, and thereafter, it increases rapidly. It is attributed to the microstructural changes like dissolution of carbides, recrystallization and grain growth. Microstructures are found to be predominantly single-phase austenitic with the presence of fine alloy carbides. The presence of twins is observed in samples heat-treated at lower temperature, which act as nucleation sites for recrystallization at 775 °C. Beyond 850 °C, the role of carbides present in the matrix is subsided by the coarsening of recrystallized grains and finally at 1025 °C, significant dissolution of carbide results in substantial reduction in strength and increase in ductility. Elongation to an extent of >71% has been obtained in sample heat-treated at 1025 °C indicating excellent tendency for cold workability. Failure of heat-treated specimens is found to be mainly due to carbide particle-matrix decohesion which acts as locations for crack initiation.

  13. Predicting outgrowth and inactivation of Clostridium perfringens in meat products during low temperature long time heat treatment

    DEFF Research Database (Denmark)

    Duan, Zhi; Holst Hansen, Terese; Hansen, Tina Beck

    OBJECTIVE Sous-vide cooking and molecular gastronomy has started a wave of experimenting with Low Temperature Long Time (LTLT) heat treatments. Heat treatments, at temperatures as low as 50°C, have been suggested by celebrity chefs. LTLT treatments often take hours to reach to the final core...

  14. Effect of grinding and heat treatment on the mechanical behavior of zirconia ceramic

    Directory of Open Access Journals (Sweden)

    Gabriela Freitas RAMOS

    2016-01-01

    Full Text Available Abstract The present study investigated the effect of grinding on roughness, flexural strength, and reliability of a zirconia ceramic before and after heat treatment. Seven groups were tested (n = 15: a control group (labeled CG, untreated, and six groups of samples ground with diamond discs, simulating diamond burs, with grits of 200 µm (G80; 160 µm (G120, and 25 µm (G600, either untreated or heat-treated at 1200°C for 2 h (labeled A. Yttria tetragonal zirconia polycrystal discs were manufactured, ground, and submitted to roughness and crystalline phase analyses before the biaxial flexural strength test. There was no correlation between roughness (Ra and Rz and flexural strength. The reliability of the materials was not affected by grinding or heat treatment, but the characteristic strength was higher after abrasion with diamond discs, irrespective of grit size. The X-ray diffraction data showed that grinding leads to a higher monoclinic (m phase content, whereas heat treatment produces reverse transformation, leading to a fraction of m-phase in ground samples similar to that observed in the control group. However, after heat treatment, only the G80A samples presented strength similar to that of the control group, while the other groups showed higher strength values. When zirconia pieces must be adjusted for clinical use, a smoother surface can be obtained by employing finer-grit diamond burs. Moreover, when the amount of monoclinic phase is related to the degradation of zirconia, the laboratory heat treatment of ground pieces is indicated for the reverse transformation of zirconia crystals.

  15. Impact of Heat Treatment on the Freezing Points of Cow and Goat Milk

    Directory of Open Access Journals (Sweden)

    Bohumíra Janštová

    2009-01-01

    Full Text Available The aim of this study was to monitor the impact of heat treatment variables on the freezing point of cow and goat milk. The freezing point (FP was established in 30 bulk tank samples of goat milk and in 30 bulk tank samples of cow milk which were subject to laboratory heat treatment at temperatures of 72 °C (A, 85 °C (B, 95 °C (C, with the same exposition times of 20 s. Freezing point measurements of raw and heat-treated milk were carried out in compliance with the Standard CTS 57 0538 by a thermistor cryoscope. The FP of raw cow milk increased with heat treatment from the initial values of -0.5252 ± 0.0114 °C (O by 0.0023 °C (A, 0.0034 °C (B and 0.0051°C (C. Changes in FP values of goat milk were detected, from its initial value of –0.5530 ± 0.0086 °C there was an increase in the FP depending on the mode of heat treatment due to pasteurization by an average of 0.0028 °C (A, 0.0036 °C (B and 0.0054 °C (C. The dynamics of the changes were similar both in goat and cow milk. Freezing point values in cow and goat milk differed (P ⪬ 0.01 when compared to the freezing point of untreated milk after the individual interventions as well as when compared between each other. An increase in the heat treatment temperature of cow and goat milk causes an increase in the freezing point (a shift towards zero. These results can be used in practice for checking the raw material in dairy industry.

  16. Evaluation of focused ultrasound algorithms: Issues for reducing pre-focal heating and treatment time.

    Science.gov (United States)

    Yiannakou, Marinos; Trimikliniotis, Michael; Yiallouras, Christos; Damianou, Christakis

    2016-02-01

    Due to the heating in the pre-focal field the delay between successive movements in high intensity focused ultrasound (HIFU) are sometimes as long as 60s, resulting to treatment time in the order of 2-3h. Because there is generally a requirement to reduce treatment time, we were motivated to explore alternative transducer motion algorithms in order to reduce pre-focal heating and treatment time. A 1 MHz single element transducer with 4 cm diameter and 10 cm focal length was used. A simulation model was developed that estimates the temperature, thermal dose and lesion development in the pre-focal field. The simulated temperature history that was combined with the motion algorithms produced thermal maps in the pre-focal region. Polyacrylimde gel phantom was used to evaluate the induced pre-focal heating for each motion algorithm used, and also was used to assess the accuracy of the simulation model. Three out of the six algorithms having successive steps close to each other, exhibited severe heating in the pre-focal field. Minimal heating was produced with the algorithms having successive steps apart from each other (square, square spiral and random). The last three algorithms were improved further (with small cost in time), thus eliminating completely the pre-focal heating and reducing substantially the treatment time as compared to traditional algorithms. Out of the six algorithms, 3 were successful in eliminating the pre-focal heating completely. Because these 3 algorithms required no delay between successive movements (except in the last part of the motion), the treatment time was reduced by 93%. Therefore, it will be possible in the future, to achieve treatment time of focused ultrasound therapies shorter than 30 min. The rate of ablated volume achieved with one of the proposed algorithms was 71 cm(3)/h. The intention of this pilot study was to demonstrate that the navigation algorithms play the most important role in reducing pre-focal heating. By evaluating in

  17. On post-weld heat treatment cracking in tig welded superalloy ATI 718Plus

    Science.gov (United States)

    Asala, G.; Ojo, O. A.

    The susceptibility of heat affected zone (HAZ) to cracking in Tungsten Inert Gas (TIG) welded Allvac 718Plus superalloy during post-weld heat treatment (PWHT) was studied. Contrary to the previously reported case of low heat input electron beam welded Allvac 718Plus, where HAZ cracking occurred during PWHT, the TIG welded alloy is crack-free after PWHT, notwithstanding the presence of similar micro-constituents that caused cracking in the low input weld. Accordingly, the formation of brittle HAZ intergranular micro-constituents may not be a sufficient factor to determine cracking propensity, the extent of heat input during welding may be another major factor that influences HAZ cracking during PWHT of the aerospace superalloy Allvac 718Plus.

  18. Influence of Heat Treatment on the Morphologies of Copper Nanoparticles Based Films by a Spin Coating Method

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2017-01-01

    Full Text Available We have investigated the influence of heat treatment on the morphologies of copper nanoparticles based films on glass slides by a spin coating method. The experiments show that heat treatment can modify the sizes and morphologies of copper nanoparticles based films on glass slides. We suggest that through changing the parameters of heat treatment process may be helpful to vary the scattering and absorbing intensity of copper nanoparticles when used in energy harvesting/conversion and optical devices.

  19. The influence of distal-end heat treatment on deflection of nickel-titanium archwire.

    Science.gov (United States)

    Silva, Marcelo Faria da; Pinzan-Vercelino, Célia Regina Maia; Gurgel, Júlio de Araújo

    2016-01-01

    The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi) orthodontic wires adjacent to the portion submitted to heat treatment. A total of 106 segments of NiTi wires (0.019 x 0.025-in) and heat-activated NiTi wires (0.016 x 0.022-in) from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40), while the other distal portion of the same archwire was used as a heating-free control group (n = 40). Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p wire. Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

  20. The influence of distal-end heat treatment on deflection of nickel-titanium archwire

    Directory of Open Access Journals (Sweden)

    Marcelo Faria da Silva

    2016-02-01

    Full Text Available Objective: The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi orthodontic wires adjacent to the portion submitted to heat treatment. Material and Methods: A total of 106 segments of NiTi wires (0.019 x 0.025-in and heat-activated NiTi wires (0.016 x 0.022-in from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40, while the other distal portion of the same archwire was used as a heating-free control group (n = 40. Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p < 0.05. Results: There were no statistically significant differences between the tested groups with the same size and brand of wire. Conclusions: Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

  1. Analysis of Thermal Stresses and Strains Developing during the Heat Treatment of Windmill Shaft

    Directory of Open Access Journals (Sweden)

    Cebo-Rudnicka A.

    2017-06-01

    Full Text Available In the paper the results of evaluation of the temperature and stress fields during four cycles of the heat treatment process of the windmill shaft has been presented. The temperature field has been calculated from the solution to the heat conduction equation over the whole heat treatment cycles of the windmill shaft. To calculate the stress field an incremental method has been used. The relations between stresses and strains have been described by Prandtl-Reuss equation for the elastic-plastic body. In order to determine the changes in the temperature and stress fields during heat treatment of the windmill shaft self-developed software utilizing the Finite Element Method has been used. This software can also be used to calculate temperature changes and stress field in ingots and other axially symmetric products. In the mathematical model of heating and cooling of the shaft maximum values of the strains have been determined, which allowed to avoid the crack formation. The critical values of strains have been determined by using modified Rice and Tracy criterion.

  2. Influence of heat treatment on physicochemical and rheological characteristics of natural yogurts

    Directory of Open Access Journals (Sweden)

    Juliana Aparecida Célia

    2017-08-01

    Full Text Available The aim of this study was to assess the influence of heat treatment on physicochemical and rheological characteristics of natural yogurts, as well as the influence of lyophilization process on natural yogurts after reconstitution. In the first experiment, three yogurt treatments were processed, as follows: Treatment 1, yogurt produced with raw refrigerated milk; Treatment 2, yogurt produced with refrigerated pasteurized milk; and Treatment 3, yogurt produced with UHT (ultra-high temperature milk, in addition to analyses of fat, protein, moisture, titratable acidity, and pH. The shelf life of yogurts at 1, 8, 15, 22, and 29 days of storage, as well as pH, acidity, syneresis, viscosity, viable lactic bacteria, and total coliforms were also assessed. In the second experiment, yogurts were submitted to lyophilization process, performed by scanning electron microscopy analysis and subsequently in those reconstituted, in addition to being assessed the physicochemical, rheological, and viable lactic bacteria characteristics. The results found in the first experiment showed that heat treatment was positive for viscosity, syneresis, and lactic bacteria, being viable until the 15th day of storage only for yogurts submitted to heat treatment. In the second experiment, lyophilization preserved the physicochemical characteristics of yogurts, but the number of initial lactic bacteria was different, also negatively affecting yogurt viscosity.

  3. Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bo [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Wang, Xiaomin, E-mail: xmwang991011@163.com [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Chen, Hui; Hu, Jie [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Huang, Cui [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Gou, Guoqing [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China)

    2016-09-05

    7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

  4. Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

    International Nuclear Information System (INIS)

    Li, Bo; Wang, Xiaomin; Chen, Hui; Hu, Jie; Huang, Cui; Gou, Guoqing

    2016-01-01

    7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

  5. Biochemical changes in full fat rice bran stabilized through microwave heating and irradiation treatment

    International Nuclear Information System (INIS)

    El-Niely, H.F.; Abaullah, M.I.

    2007-01-01

    The effect of microwave heating and irradiation treatments on proximate composition, lipoxygenase (LOX) activity, free fatty acid (FFA) and fatty acids profile of full fat rice bran were examined. Full fat raw rice bran (FRB) (82.7 g / kg moisture content) was heated in microwave oven at 850 W for up to 4 min or exposed to gamma irradiation up to 25 KGy then packed in polyethylene bags and stored at room temperature for 6 months. Water, protein, fat, ash and crude fiber contents did not change significantly in raw, microwave heated and irradiated samples before and after storage. An exception for this general observation was observed for the moisture content of FRB processed through microwave heating where heating FRB for 4 min dropped the level of moisture to 64.3 g / kg at zero time. Storage of both raw and processed samples had significant (P<0.05) effects on LOX activity. LOX activity of raw samples was significantly increased from its initial value by 43.5% after storage for six months. Microwave heat and irradiated samples showed deactivated LOX and samples exhibited significant changes in LOX activity could be due to treatment dosage. Meanwhile, significant change in LOX activity was observed in processed samples stored for six months. Minor changes were observed due to applied processing methods on FFA and fatty acids composition of full fat rice bran before and after storage. The results suggested that microwave heated or irradiated full fat rice bran packed in polyethylene bags can be stored at room temperature for six months without adverse effect on proximate, fatty acid composition quality and could prevent oxidative and hydrolytic rancidity. However, gamma irradiation treatment at 25 KGy was more effective in this respect. Therefore, it could be concluded that gamma irradiation contributed to optimal processing conditions for FRB stabilization

  6. Tratamento térmico para controle da lanosidade em pêssegos 'Dourado-2' refrigerados Heat treatment to alleviation of woolliness of cold stored 'Dourado-2' peach

    Directory of Open Access Journals (Sweden)

    Daniela Cristina Clemente Vitti

    2007-12-01

    were: incidence of woolliness and decay, soluble solids content (SSC, acidity, ascorbic acid, skin color, firmness, respiratory rate, ethylene production and activity of polygalacturonase (PG and pectinmethylesterase (PME. The intermittent warming with cycles of five or ten days and the conditioning temperature at 20ºC during 48 hours before cold storage was the most effective treatment to reduce incidence of woolliness. However, heat treatment hastened fruit softening. Ethylene production was higher in fruits intermittently warmed and this can be related to the higher activity of PG and PME and consequently to alleviation of woolliness of the fruit. Heat treatment caused little variations on SSC, acidity, ascorbic acid and skin color.

  7. Microsegregation of heat and homogenization treatments in uranium-niobium alloys (U-Nb)

    International Nuclear Information System (INIS)

    Leal, J.F.

    1988-01-01

    In the following sections microsegration results in U-3,6 Wt% Nb and U-6,1 Wt% Nb alloys casted in noconsumable electrode arc furnace are presented. The microsegration is studied qualitatively by optical microscopy and quantitatively by electron microprobe. The degree of homogenization has been measured after 800 and 850 0 C heat treatments in tubular resistive furnace. The microstructures after heat treatments are quantitatively analysed to check effects on the casting structures, mainly the variations in solute along the dendrite arm spacing. Some solidification phenomena are then discussed on reference to theorical models of dendritic solidification, including microstructure and microsegregation. The experimental results are compared to theoretical on basis of initial and residual microsegregation after homogenization treatments. The times required for homogenization of the alloys are also discussed in function of the microsegregation from casting structures and the temperatures of the treatments. (author) [pt

  8. Implantable polymer/metal thin film structures for the localized treatment of cancer by Joule heating

    Science.gov (United States)

    Kan-Dapaah, Kwabena; Rahbar, Nima; Theriault, Christian; Soboyejo, Wole

    2015-04-01

    This paper presents an implantable polymer/metal alloy thin film structure for localized post-operative treatment of breast cancer. A combination of experiments and models is used to study the temperature changes due to Joule heating by patterned metallic thin films embedded in poly-dimethylsiloxane. The heat conduction within the device and the surrounding normal/cancerous breast tissue is modeled with three-dimensional finite element method (FEM). The FEM simulations are used to explore the potential effects of device geometry and Joule heating on the temperature distribution and lesion (thermal dose). The FEM model is validated using a gel model that mimics biological media. The predictions are also compared to prior results from in vitro studies and relevant in vivo studies in the literature. The implications of the results are discussed for the potential application of polymer/metal thin film structures in hyperthermic treatment of cancer.

  9. Effect of intercritical heat treatment on mechanical properties of reinforcing steel bars

    International Nuclear Information System (INIS)

    Abro, M.I.; Memon, R.A.; Soomro, I.A.; Aftab, U.

    2017-01-01

    Intercritical heat treatments attempts were made to enhance the mechanical properties of reinforcing steel bars milled from scrap metal. For this, two grades of steel bars were obtained from different steel mills and their mechanical properties that include hardness, ultimate tensile strength, and percent elongation before and after intercritical heat treatment were determined. Results indicated that 25.5 and 17.6%, improvements in UTS (Ultimate Tensile Strength) and 18.8 and 14.3% improvement in percent elongation in two grades of reinforcing steel samples containing 0.17 and 0.24% carbon respectively was achieved while heating at 750 degree C for 2h. Appreciable improvement in the mechanical properties was noted due to birth of sufficient quantity of martensite along with ferrite. (author)

  10. Effect of Heat Treatment on the Surface Properties of Activated Carbons

    Directory of Open Access Journals (Sweden)

    Meriem Belhachemi

    2011-01-01

    Full Text Available This work reports the effect of heat treatment on the porosity and surface chemistry of two series of activated carbons prepared from a local agricultural biomass material, date pits, by physical activation with carbon dioxide and steam. Both series samples were oxidized with nitric acid and subsequently heat treated under N2 at 973 K in order to study the effect of these treatments in porosity and surface functional groups of activated carbons. When the activated carbons were heat treated after oxidation the surface area and the pore volume increase for both activated carbons prepared by CO2 and steam activations. However the amount of surface oxygen complexes decreases, the samples keep the most stable oxygen surface groups evolved as CO by temperature-programmed desorption experiments at high temperature. The results show that date pits can be used as precursors to produce activated carbons with a well developed porosity and tailored oxygen surface groups.

  11. Effects of heat treatment to the sound velocity and microstructural changes of ASTM A516 steels

    International Nuclear Information System (INIS)

    Norasiah Abdul Kasim; Azali Muhammad; Amry Amin Abas; Zaiton Selamat

    2010-01-01

    Full-text: The used of ultrasonic testing as a thickness measurement for structural components (pipeline and pressure vessel) is among the popular inspection tool widely use in the industrial power plant such as at petrochemical and nuclear power plant. Currently, there are cases where the thickness grows and the result will affect the reliability of the test. There are many factors that can affect the reliability of measurement. One of it is the material under test itself. In the Malaysian Nuclear Agency, initial efforts are underway to study the understanding on the effects of heat treatment to the sound velocity and microstructure changes of ASTM A516 steel. Few samples of thin square shaped prepared were heat treated under the following conditions: austenitization at 9800 degree Celsius - 2 hours, quenching; tempering at various temperature 4000, 5000, 6000 and 7000 degree Celsius. The results show that the microstructure changes and samples exhibit different sound velocity at different heat treatment. (author)

  12. A Method to Make Classification of the Heat Treatment Processes Performed on Bronze Using Incomplete Knowledge

    Directory of Open Access Journals (Sweden)

    Kluska-Nawarecka S.

    2014-06-01

    Full Text Available The article describes the problem of selection of heat treatment parameters to obtain the required mechanical properties in heat- treated bronzes. A methodology for the construction of a classification model based on rough set theory is presented. A model of this type allows the construction of inference rules also in the case when our knowledge of the existing phenomena is incomplete, and this is situation commonly encountered when new materials enter the market. In the case of new test materials, such as the grade of bronze described in this article, we still lack full knowledge and the choice of heat treatment parameters is based on a fragmentary knowledge resulting from experimental studies. The measurement results can be useful in building of a model, this model, however, cannot be deterministic, but can only approximate the stochastic nature of phenomena. The use of rough set theory allows for efficient inference also in areas that are not yet fully explored.

  13. Measurement of heat treatment induced residual stresses by using ESPI combined with hole-drilling method

    Directory of Open Access Journals (Sweden)

    Jie Cheng

    2010-08-01

    Full Text Available In this study, residual stresses in heat treated specimen were measured by using ESPI (Electronic Speckle-Pattern Interferometry combined with the hole-drilling method. The specimen, made of SUS 304 austenitic stainless steel, was quenched and water cooled to room temperature. Numerical simulation using a hybrid FDM/FEM package was also carried out to simulate the heat treatment process. As a result, the thermal stress fields were obtained from both the experiment and the numerical simulation. By comparision of stress fields, results from the experimental method and numerical simulation well agreed to each other, therefore, it is proved that the presented experimental method is applicable and reliable for heat treatment induced residual stress measurement.

  14. Evaluation of heat treatment schedules for emerald ash borer (Coleoptera: Buprestidae).

    Science.gov (United States)

    Myers, Scott W; Fraser, Ivich; Mastro, Victor C

    2009-12-01

    The thermotolerance of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), was evaluated by subjecting larvae and prepupae to a number of time-temperature regimes. Three independent experiments were conducted during 2006 and 2007 by heating emerald ash borer infested firewood in laboratory ovens. Heat treatments were established based on the internal wood temperature. Treatments ranged from 45 to 65 degrees C for 30 and 60 min, and the ability of larvae to pupate and emerge as adults was used to evaluate the success of each treatment. A fourth experiment was conducted to examine heat treatments on exposed prepupae removed from logs and subjected to ambient temperatures of 50, 55, and 60 degrees C for 15, 30, 45, and 60 min. Results from the firewood experiments were consistent in the first experiment. Emergence data showed emerald ash borer larvae were capable of surviving a temperatures-time combination up to 60 degrees C for 30 min in wood. The 65 degrees C for 30 min treatment was, however, effective in preventing emerald ash borer emergence on both dates. Conversely, in the second experiment using saturated steam heat, complete mortality was achieved at 50 and 55 degrees C for both 30 and 60 min. Results from the prepupae experiment showed emerald ash borer survivorship in temperature-time combinations up to 55 degrees C for 30 min, and at 50 degrees C for 60 min; 60 degrees C for 15 min and longer was effective in preventing pupation in exposed prepupae. Overall results suggest that emerald ash borer survival is variable depending on heating conditions, and an internal wood temperature of 60 degrees C for 60 min should be considered the minimum for safe treatment for firewood.

  15. Hardening and softening analysis of pure titanium based on the dislocation density during torsion deformation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Han; Li, Fuguo, E-mail: fuguolx@nwpu.edu.cn; Li, Jinghui; Ma, Xinkai; Li, Jiang; Wan, Qiong

    2016-08-01

    The hardening and softening phenomena during torsion deformation are studied based on the Taylor dislocation model for pure titanium. The hardening and softening phenomena are observed through the hardness analysis during micro-indentation test and micro-hardness test. Besides, the variations of indentation size also verify the existence of hardening and softening phenomena during torsion. The variations of geometric necessary dislocations (GNDs) and statistic store dislocations (SSDs) state that the positions of high dislocation density and low dislocation density correspond to the positions of hardening and softening. The results from the microstructure, grain boundaries evolution and twins analysis indicate the twins play an important role in appearance of hardening and softening phenomena. The appearance of hardening and softening phenomena are attributed to the combination of different slip systems and twinning systems combining with the Schmid Factor (SF) analysis and the transmission electron microscope (TEM). The appearance of hardening and softening phenomena can be explained by the Taylor dislocation theory based on TEM analysis. - Highlights: • The phenomena can be characterized by Taylor dislocation model. • The variation of GNDs leads to the phenomena. • The phenomena are proved by micro-hardness, indentation hardness. • The {10-12} twin and {11-24} twin play an important role in the phenomena.

  16. Heat treatment effect on the mechanical properties of industrial drawn copper wires

    International Nuclear Information System (INIS)

    Beribeche, Abdellatif; Boumerzoug, Zakaria; Ji, Vincent

    2013-01-01

    In this present investigation, the mechanical properties of industrial drawn copper wires have been studied by tensile tests. The effect of prior heat treatments at 500°C on the drawn wires behavior was the main goal of this investigation. We have found that the mechanical behavior of drawn wires depends strongly on those treatments. SEM observations of the wire cross section after tensile tests have shown that the mechanism of rupture was mainly controlled by the void formation

  17. Successful Treatment of Cutaneous Botryomycosis with a Combination of Minocycline and Topical Heat Therapy

    Directory of Open Access Journals (Sweden)

    Masaya Ishibashi

    2012-05-01

    Full Text Available Cutaneous botryomycosis is a chronic focal infection characterized by a granulomatous inflammatory response to bacterial pathogens such as Staphylococcus aureus. Treatment requires antibiotic therapy and may also require surgical debridement. We employed topical heat therapy and oral minocycline. The lesions became flattened and pigmented after 1 month. We consider that this simple treatment can be an effective and harmless complementary therapy for cutaneous botryomycosis.

  18. Enhancement of contractile force generation of artificial skeletal muscle tissues by mild and transient heat treatment.

    Science.gov (United States)

    Sato, Masanori; Ikeda, Kazushi; Kanno, Shota; Ito, Akira; Kawabe, Yoshinori; Kamihira, Masamichi

    2014-01-01

    Artificial skeletal muscle tissues composed of cells are expected to be used for applications of regenerative medicine and drug screening. Generally, however, the physical forces generated by tissue-engineered skeletal muscle are lower than those of skeletal muscle tissues found in the body. Local hyperthermia is used for many diseases including muscle injuries. It was recently reported that mild heat treatment improved skeletal muscle functions. In this study, we investigated the effects of mild heat treatment on the tissue-engineered skeletal muscle tissues in vitro. We used magnetite cationic liposomes to label C2C12 myoblast cells magnetically, and constructed densely packed artificial skeletal muscle tissues by using magnetic force. Cell culture at 39°C promoted the differentiation of myoblast cells into myotubes. Moreover, the mild and transient heat treatment improved the contractile properties of artificial skeletal muscle tissue constructs. These findings indicate that the culture method using heat treatment is a useful approach to enhance functions of artificial skeletal muscle tissue.

  19. Effect of prolonged isothermal heat treatment on the mechanical behavior of advanced NANOBAIN steel

    Science.gov (United States)

    Avishan, Behzad

    2017-09-01

    The microstructural evolution and consequent changes in strength and ductility of advanced NANOBAIN steel during prolonged isothermal heat-treatment stages were investigated. The microstructure and mechanical properties of nanostructured bainite were not expected to be influenced by extending the heat-treatment time beyond the optimum value because of the autotempering phenomenon and high tempering resistance. However, experimental results indicated that the microstructure was thermodynamically unstable and that prolonged austempering resulted in carbon depletion from high-carbon retained austenite and carbide precipitations. Therefore, austenite became thermally less stable and partially transformed into martensite during cooling to room temperature. Prolonged austempering did not lead to the typical tempering sequence of bainite, and the sizes of the microstructural constituents were independent of the extended heat-treatment times. This independence, in turn, resulted in almost constant ultimate tensile strength values. However, microstructural variations enhanced the yield strength and the hardness of the material at extended isothermal heat-treatment stages. Finally, although microstructural changes decreased the total elongation and impact toughness, considerable combinations of mechanical properties could still be achieved.

  20. Effect of heat treatment and shelf life on chilling injury of mango cv. Nam Dok Mai

    Directory of Open Access Journals (Sweden)

    Apiradee Muangdech

    2017-10-01

    Full Text Available This study was aimed to investigate the effect of heat treatment and shelf life on chilling injury of mango cv.Nam Dok Mai.The heat treatment of mango pulp during storage were determined by hot air oven set at 34 and 38°C for three intervals, as 24, 48, and 72 hours, then they were subsequently stored at 5°C for 10, 20, and 30 days to determine the appropriate shelf life. The findings showed that the symptom of mango fruit after chilling injury appeared within the 30th day of storage at 5°C. Several symptoms of mango fruit after chilling injury treatment were observed, i.e., pitting, browning on the skin, water soaking, and rapid rotting of the fruits that resulted in shorter shelf life. It was found that chilling injury mangoes had lower level of total soluble solid, higher disease incidence, and lower quality of fruit when compared with normal ripe-mango fruits at 25°C. Mango fruits treated at 34°C for either 24 or 48 hours, and at 38°C for 24 hours prior to cold storage at 5°C for 10 and 20 days showed a significant reduction in the chilling injury (CI index when compared to that of non-heated fruits. On the other hand, the heat treatment did not affect fruit weight loss, firmness, color changes, and water soaking at 5°C.

  1. Effect of T6 heat treatment on damping characteristics of Al/RHA ...

    Indian Academy of Sciences (India)

    Abstract. In the present work, effect of T6 heat treatment on the damping behaviour of aluminum/rice husk ash .... alloy-based composites, there is dearth of information on the damping ... fication. Using the process 4, 6 and 8% by weight, RHA.

  2. Ruminal biohydrogenation kinetics of defatted flaxseed and sunflower is affected by heat treatment

    DEFF Research Database (Denmark)

    Lashkari, Saman; Hymøller, Lone; Jensen, Søren Krogh

    2017-01-01

    The effect of heat treatment on biohydrogenation of linoleic acid (LA) and linolenic acid (LNA) and formation of stearic acid (SA), cis-9, trans-11 conjugated LA (CLA), trans-10, cis-12 CLA and trans-vaccenic acid (VA) was studied in in vitro incubations with diluted rumen fluid as inoculum...

  3. Expanded heat treatment to form residual compressive hoop stress on inner surface of zirconium alloy tubing

    International Nuclear Information System (INIS)

    Megata, Masao

    1997-01-01

    A specific heat treatment process that introduces hoop stress has been developed. This technique can produce zirconium alloy tubing with a residual compressive hoop stress near the inner surface by taking advantage of the mechanical anisotropy in hexagonal close-packed zirconium crystal. Since a crystal having its basal pole parallel to the tangential direction of the tubing is easier to exhibit plastic elongation under the hoop stress than that having its basal pole parallel to the radial direction, the plastic and elastic elongation can coexist under a certain set of temperature and hoop stress conditions. The mechanical anisotropy plays a role to extend the coexistent stress range. Thus, residual compressive hoop stress is formed at the inner surface where more plastic elongation occurs during the heat treatment. This process is referred to as expanded heat treatment. Since this is a fundamental crystallographic principle, it has various applications. The application to improve PCI/SCC (pellet cladding interaction/stress corrosion cracking) properties of water reactor fuel cladding is promising. Excellent results were obtained with laboratory-scale heat treatment and an out-reactor iodine SCC test. These results included an extension of the time to SCC failure. (author)

  4. T5 heat treatment of semi-solid metal processed aluminium alloy F357

    CSIR Research Space (South Africa)

    Moller, H

    2009-04-01

    Full Text Available The T5 heat treatment of semi-solid metal (SSM) processed alloy F357 was investigated by considering the effects of cooling rate and natural aging after casting, as well as artificial aging parameters on tensile properties. In addition, the tensile...

  5. Effects of heat treatment on antioxidative and anti-inflammatory properties of orange by-products

    Science.gov (United States)

    This study investigated the changes in functional components, antioxidative activities, antibacterial activities, anti-inflammatory activities of orange (Citrus sinensis (L.) Osbeck) by-products (OBP) by heat treatment at 50 and 100 degrees C (hereafter, 50D and 100D extracts, respectively). Optimal...

  6. Comparison of the heat treatment response of wrought and SSM-HPDC alloy 6082

    CSIR Research Space (South Africa)

    Möller, H

    2011-06-01

    Full Text Available The natural and artificial aging responses of wrought and SSM-HPDC alloy 6082 are compared. It is shown that the heat treatment response of this Al-Mg-Si alloy is not influenced by differences in microstructures produced by different processing...

  7. Influence of heat treatment and veneering on the storage modulus and surface of zirconia ceramic

    NARCIS (Netherlands)

    Siavikis, G.; Behr, M.; van der Zel, J.M.; Feilzer, A.J.; Rosentritt, M.

    2011-01-01

    Objectives: Glass-ceramic veneered zirconia is used for the application as fixed partial dentures. The aim of this investigation was to evaluate whether the heat treatment during veneering, the application of glass-ceramic for veneering or long term storage has an influence on the storage modulus of

  8. THE EFFECT OF HEAT TREATMENT ON THE DURABILITY OF BAMBOO Gigantochloa scortechinii

    Directory of Open Access Journals (Sweden)

    Norashikin Kamarudin

    2012-07-01

    Full Text Available Bamboo signifies as one of the fastest growing plants and it can be used for various products. In tropical countries such as Indonesia and Malaysia, bamboo is abundantly available at reasonable prices, therefore it is used for numerous purposes. However, as lignocellulosic material, bamboo is susceptible to fungal and insect attacks. Heat treatment is an option to improve bamboo's durability. The objective of this study was to improve the durability of bamboo using hot oil palm treatment. A Malaysian grown bamboo species, Buluh Semantan (Gigantochloa scortechinii, as a study material was soaked in hot oil palm for various temperatures and soaking time, before being inoculated with the basidiomycete Coriolus versicolor in an agar block test. The results demonstrated that the longer the heating time, the more improved the durability of bamboo. Altering the temperature in the palm oil treatment produced varying results. Bamboo blocks that heated in hot oil palm at 100°C for 60 minutes shows considerably less weight eduction that indicates less fungal attack. Overall, the higher the temperature, the better the durability of bamboo. Please indicates what the meaning of heat treatment in this experiment, it is not clear.

  9. Effect of solution heat treatment time on a rheocast Al-Zn-Mg-Cu alloy

    CSIR Research Space (South Africa)

    Mazibuko, NE

    2011-06-01

    Full Text Available During rheo-high pressure die casting (R-HPDC) of Al-Zn-Mg-Cu alloys a coarse eutectic phase is formed. This eutectic phase is difficult to take into solution because of its size and it would require longer solution heat treatment times...

  10. Effect of heat treatment and artificial ageing on Al-5Mg-2Zn

    CSIR Research Space (South Africa)

    Chauke, Levy

    2017-10-01

    Full Text Available ageing of Al-5Mg-2Zn. The study showed intermetallic phases at the grain boundaries and a melting peak at about 476 °C for the F condition. Solution heat treatment at 440°C for 4 hours dissolved the intermetallic phase thus increasing the melting point...

  11. Combined action of S-carvone and mild heat treatment on Listeria monocytogenes Scott A

    NARCIS (Netherlands)

    Karatzas, A.K.; Bennik, M.H.J.; Smid, E.J.; Kets, E.P.W.

    2000-01-01

    The combined action of the plant-derived volatile, S-carvone, and mild heat treatment on the food-borne pathogen, Listeria monocytogenes, was evaluated. The viability of exponential phase cultures grown at 8 °C could be reduced by 1.3 log units after exposure to S-carvone (5 mmol 1-1) for 30 min at

  12. The Effects of pH and Heat Treatment Processing on the Stability of ...

    African Journals Online (AJOL)

    This study was carried out to investigate the effects of pH and heat treatment processing on stability and natural food colours used in dairy products. A repeated laboratory experiment was conducted in which loss of colour intensity or change in shade of natural food colours used in acid and nearly neutral dairy products at ...

  13. Statement on a heat treatment to control Agrilus planipennis

    DEFF Research Database (Denmark)

    Baker, R.; Candresse, T.; Dormannsné Simon, E.

    2012-01-01

    , to clarify its conclusion and indicate what data would be needed to assess the effectiveness of the new treatment. The Panel concluded that the new proposal is not within the scope of the opinion as the data provided by the US Authorities cannot be used to evaluate the effectiveness of the new proposed heat...

  14. Effect of heat treatment on strength and abrasive wear behaviour of ...

    Indian Academy of Sciences (India)

    In the present investigation Al6061–SiCp composites was fabricated by liquid metallurgy route with percentages of SiCp varying from 4 wt% to 10 wt% in steps of 2 ... However, under identical heat treatment conditions, adopted Al6061–SiCp composites exhibited better microhardness and tensile strength reduced wear loss ...

  15. Treatment of Phlegm- and Heat-induced Insomnia by Acupuncture in 120 Cases

    Institute of Scientific and Technical Information of China (English)

    崔芮; 周德安

    2003-01-01

    @@ Clinical Data The 120 cases in this series were outpatients suffering from insomnia due to interior-stirring by phlegm-heat, ranging in age from 28 to 67 years. They were randomly divided into a treatment group and a control group.

  16. Numerical analysis of heat treatment of TiCN coated AA7075 aluminium alloy

    Science.gov (United States)

    Srinath, M. K.; Prasad, M. S. Ganesha

    2018-04-01

    The Numerical analysis of heat treatments of TiCN coated AA7075 aluminium alloys is presented in this paper. The Convection-Diffusion-Reaction (CDR) equation with solutions in the Streamlined-Upward Petrov-Galerkin (SUPG) method for different parameters is provided for the understanding of the process. An experimental process to improve the surface properties of AA-7075 aluminium alloy was attempted through the coatings of TiCN and subsequent heat treatments. From the experimental process, optimized temperature and time was obtained which gave the maximum surface hardness and corrosion resistance. The paper gives an understanding and use of the CDR equation for application of the process. Expression to determine convection, diffusion and reaction parameters are provided which is used to obtain the overall expression of the heat treatment process. With the substitution of the optimized temperature and time, the governing equation may be obtained. Additionally, the total energy consumed during the heat treatment process is also developed to give a mathematical formulation of the energy consumed.

  17. Effect of heat treatment on strength and abrasive wear behaviour of ...

    Indian Academy of Sciences (India)

    Administrator

    Aluminum 6061 has been used as matrix material owing to its ... Mechanical properties such as microhardness, tensile strength, and abrasive wear tests have been ... heat treatment conditions, adopted Al6061–SiCp composites exhibited better microhardness and tensile ... corrosion resistance (Ramesh et al 2005).

  18. Heat treatment temperature influence on ASTM A890 GR 6A super duplex stainless steel microstructure

    International Nuclear Information System (INIS)

    Martins, Marcelo; Casteletti, Luiz Carlos

    2005-01-01

    Duplex and super duplex stainless steels are ferrous alloys with up to 26% chromium, 8% nickel, 5% molybdenum and 0.3% nitrogen, which are largely used in applications in media containing ions from the halogen family, mainly the chloride ion (Cl - ). The emergence of this material aimed at substituting Copper-Nickel alloys (Cupro-Nickel) that despite presenting good corrosion resistance, has mechanical properties quite inferior to steel properties. The metallurgy of duplex and super duplex stainless steel is complex due to high sensitiveness to sigma phase precipitation that becomes apparent, due to the temperatures they are exposed on cooling from solidification as well as from heat treatment processes. The objective of this study was to verify the influence of heat treating temperatures on the microstructure and hardness of ASTM A890/A890M Gr 6A super duplex stainless steel type. Microstructure control is of extreme importance for castings, as the chemical composition and cooling during solidification inevitably provide conditions for precipitation of sigma phase. Higher hardness in these materials is directly associated to high sigma phase concentration in the microstructure, precipitated in the ferrite/austenite interface. While heat treatment temperature during solution treatment increases, the sigma phase content in the microstructure decreases and consequently, the material hardness diminishes. When the sigma phase was completely dissolved by the heat treatment, the material hardness was influenced only due to ferrite and austenite contents in the microstructure

  19. Simulation of stretch forming with intermediate heat treatments of aircraft skins - A physically based modeling approach

    NARCIS (Netherlands)

    Kurukuri, S.; Miroux, Alexis; Wisselink, H.H.; van den Boogaard, Antonius H.

    2011-01-01

    In the aerospace industry stretch forming is often used to produce skin parts. During stretch forming a sheet is clamped at two sides and stretched over a die, such that the sheet gets the shape of the die. However for complex shapes it is necessary to use expensive intermediate heat-treatments in

  20. Effect of heat treatment changes on swelling treatment of coal; Sekitan no bojun shori sayo ni oyobosu netsushori henka no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Satsuka, T.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology

    1996-10-28

    Discussions were given on effects of heat treatment at relatively low temperatures as a pretreatment for coal liquefaction on coal swelling and hydrogenolysis reaction. Taiheiyo coal was heated to 200{degree}C for one hour as a pretreatment. The attempted heating methods consisted of four steps of rapid heating (6.7{degree}C/min)quenching (20{degree}C/min), rapid heating/natural cooling (0.7{degree}C/min), heating (1.0{degree}C/min)/quenching, and heating/natural cooling. The swelling treatment was composed of adding methanol benzene into heat treated coal, and leaving it at room temperature for 24 hours. The hydrogenolysis was carried out by using a tetralin solvent and at an initial hydrogen pressure of 20 kg/cm{sup 2} and a temperature of 350{degree}C and for a time of one hour. Hydrogenolysis conversion in the heat treated coal was found lower than that of the original coal because of generation of liquefaction inactive components due to thermal polymerization. When the heat treated coal is swollen by using the solvent, gas yield from the hydrogenolysis reaction decreased due to gas suppression effect, and the conversion was lower than that of the original coal. Heat treatment suggests densification of the coal structure. Swollen coal shows no conspicuous difference in the heat treatment methods against the hydrogenolysis due to the swelling effect. 3 refs., 5 figs., 1 tab.

  1. Effect of Shortened Heat Treatment on the Hardness and Microstructure of 320.0 Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Pezda J.

    2014-06-01

    Full Text Available Improvement of Al-Si alloys properties in scope of classic method is connected with change of Si precipitations morphology through: using modification of the alloy, maintaining suitable temperature of overheating and pouring process, as well as perfection of heat treatment methods. Growing requirements of the market make it necessary to search after such procedures, which would quickly deliver positive results with simultaneous consideration of economic aspects. Presented in the paper shortened heat treatment with soaking of the alloy at temperature near temperature of solidus could be assumed as the method in the above mentioned understanding of the problem. Such treatment consists in soaking of the alloy to temperature of solutioning, keeping in such temperature, and next, quick quenching in water (20 °C followed by artificial ageing. Temperature ranges of solutioning and ageing treatments implemented in the adopted testing plan were based on analysis of recorded curves from the ATD method. Obtained results relate to dependencies and spatial diagrams describing effect of parameters of the solutioning and ageing treatments on HB hardness of the investigated alloy and change of its microstructure. Performed shortened heat treatment results in precipitation hardening of the investigated 320.0 alloy, what according to expectations produces increased hardness of the material.

  2. Microstructure and mechanical properties of reactor pressure vessel mock-up material treated by intercritical heat treatment

    International Nuclear Information System (INIS)

    Kim, M. C.; Lee, B. S.; Hong, J. H.; Lee, H. J.; Park, S. D.; Kim, K. B.; Yoon, J. H.; Kim, J. S.; Oh, J. M.

    2003-12-01

    The mechanical properties and microstructures of base metal and weld HAZ (Heat-Affected Zone) of a Mn-Mo-Ni low alloy steels treated by intercritical heat treatment were investigated to evaluate effects of intercritical heat treatment on mechanical properties. In order to clarify the effects of intercritical heat treatment, two types of specimen were prepared by CHT(Conventional Heat Treatment) and IHT(CHT+Intercritical Heat Treatment). Tensile test, charpy impact test and vickers hardness test were carried out to evaluate the mechanical properties. It is found that impact toughness and hardness were improved by intercritical heat treatment. Mean size of precipitates and effective grain were quantitatively analysed as microstructural factors. It is found that precipitate size was decreased and shape of precipitate was spherodized by intercritical heat treatment and grain size was also decreased. So, it is thought that these microstructural changes cause the improvement of mechanical properties by intercritical heat treatment. The simulated specimen using a Gleeble thermal simulator system was used to evaluate the mechanical properties of HAZ. It is well known that IRHAZ and SRHAZ have lower toughness than base metal. However, in the case of IHT, impact toughness of IRHAZ and SRHAZ were slightly higher than that of base metal. It is obvious that this improvement of fracture toughness in IRHAZ and SRHAZ region was closely related to the microstructural changes, such as spheroidization of precipitate and decreases of precipitate size and grain size

  3. Investigation of heat treatment conditions of structural material for blanket fabrication process

    International Nuclear Information System (INIS)

    Hirose, Takanori; Suzuki, Satoshi; Akiba, Masato; Shiba, Kiyoyuki; Sawai, Tomotsugu; Jitsukawa, Shiro

    2004-01-01

    This paper presents recent results of thermal hysteresis effects on ceramic breeder blanket structural material. Reduced activation ferritic/martensitic (RAF) steel is the leading candidates for the first wall structural materials of breeding blankets. RAF steel demonstrates superior resistance to high dose neutron irradiation, because the steel has tempered martensite structure which contains the number of sink site for radiation defects. This microstructure obtained by two-step heat treatment, first is normalizing at temperature above 1200 K and the second is tempering at temperature below 1100 K. Recent study revealed the thermal hysteresis has significant impacts on the post-irradiation mechanical properties. The breeding blanket has complicated structure, which consists of tungsten armor and thin first wall with cooling pipe. The blanket fabrication requires some high temperature joining processes. Especially hot isostatic pressing (HIP) is examined as a near-net-shape fabrication process for this structure. The process consists of heating above 1300 K and isostatic pressing at the pressure above 150 MPa followed by tempering. Moreover ceramics pebbles are packed into blanket module and the module is to be seamed by welding followed by post weld heat treatment in the final assemble process. Therefore the final microstructural features of RAFs strongly depend on the blanket fabrication process. The objective of this work is to evaluate the effects of thermal hysteresis corresponding to blanket fabrication process on RAFs microstructure in order to establish appropriate blanket fabrication process. Japanese RAFs F82H (Fe-0.1C-8Cr-2W-0.2V-0.05Ta) was investigated by metallurgical method after isochronal heat treatment up to 1473 K simulating high temperature bonding process. Although F82H showed significant grain growth after conventional solid HIP conditions (1313 K x 2 hr.), this coarse grained microstructure was refined by the post HIP normalizing at

  4. Cyclically induced softening due to low-angle boundary annihilation in a martensitic steel

    International Nuclear Information System (INIS)

    Sauzay, Maxime; Brillet, Helene; Monnet, Isabelle; Mottot, Michel; Barcelo, Francoise; Fournier, Benjamin; Pineau, Andre

    2005-01-01

    Martensitic steels are known for their softening during cyclic tests carried out at high temperature. The softening has been at least partially explained by lath and sub-grain boundary elimination. This article is dedicated to an attempt at modelling both phenomena. Thanks to mechanical tests it is shown that the softening is mainly due to a decrease of the backstress. Transmission electron microscopy allows us to propose a mechanism of low-angle boundary elimination. Annihilation between dislocations of low-angle boundaries and incident mobile dislocations is modelled. The macroscopic backstress is finally computed using a Hall-Petch law and the Taylor model

  5. Experimental evidence of zone-center optical phonon softening by accumulating holes in thin Ge

    Directory of Open Access Journals (Sweden)

    Shoichi Kabuyanagi

    2016-01-01

    Full Text Available We discuss the impact of free carriers on the zone-center optical phonon frequency in germanium (Ge. By taking advantage of the Ge-on-insulator structure, we measured the Raman spectroscopy by applying back-gate bias. Phonon softening by accumulating holes in Ge film was clearly observed. This fact strongly suggests that the phonon softening in heavily-doped Ge is mainly attributed to the free carrier effect rather than the dopant atom counterpart. Furthermore, we propose that the free carrier effect on phonon softening is simply understandable from the viewpoint of covalent bonding modification by free carriers.

  6. Nonlinear response to the multiple sine wave excitation of a softening--hardening system

    International Nuclear Information System (INIS)

    Koplik, B.; Subudhi, M.; Curreri, J.

    1979-01-01

    In studying the earthquake response of the HTGR core, it was observed that the system can display softening--hardening characteristics. This is of great consequence in evaluating the structural safety aspects of the core. In order to obtain a better understanding of the governing parameters, an investigation was undertaken with a single-degree-of-freedom system having a softening--hardening spring characteristic and excited by multiple sine waves. A parametric study varying the input amplitudes and the spring characteristic was performed. Transients were introduced into the system, and the jump phenomena between the lower softening characteristics to the higher hardening curve was studied

  7. Analysis of Balanced Double Lap Joints with a Bi-Linear Softening Adhesive

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik; Schmidt, Jacob Wittrup

    2010-01-01

    of cracked concrete disks strengthened with adhesive bonded fiber reinforced polymers (FRP), or in any other structure comparable to a double lap joint with a softening interface. The present constitutive model can be changed to fit any model with the same shape of constitutive relationship, see Figure 1.......The response of a bonded symmetric balanced double lap joint under tensile loading with a bilinear softening adhesive is described with a closed form solution. Since bonded joints in concrete structures undergo softening, a versatile model to describe the response for a wide range of constitutive...

  8. Effect of heat treatment on anodic activation of aluminium by trace element indium

    Energy Technology Data Exchange (ETDEWEB)

    Graver, Brit [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Helvoort, Antonius T.J. van [Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Nisancioglu, Kemal, E-mail: kemal.nisancioglu@material.ntnu.n [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2010-11-15

    Research highlights: {yields} Indium segregation activates AlIn alloy surface anodically in chloride solution. {yields} Enrichment of In on Al surface can occur thermally by heat treatment at 300 {sup o}C. {yields} Increasing temperature homogenises indium in aluminium reducing anodic activation. {yields} Indium can activate AlIn surface by segregating through dealloying of aluminium. {yields} Anodic activation is caused by AlIn amalgam formation at aluminium surface. - Abstract: The presence of trace elements in Group IIIA-VA is known to activate aluminium anodically in chloride environment. The purpose of this paper is to investigate the surface segregation of trace element In by heat treatment and resulting surface activation. Model binary AlIn alloys, containing 20 and 1000 ppm by weight of In, were characterized after heat treatment at various temperatures by use of glow discharge optical emission spectroscopy, electron microscopy and electrochemical polarization. Heat treatment for 1 h at 300 {sup o}C gave significant segregation of discrete In particles (thermal segregation), which activated the surface. Indium in solid solution with aluminium, obtained by 1 h heat treatment at 600 {sup o}C, also activated by surface segregation of In on alloy containing 1000 ppm In, resulting from the selective dissolution of the aluminium component during anodic oxidation (anodic segregation). The effect of anodic segregation was reduced by decreasing indium concentration in solid solution; it had negligible effect at the 20 ppm level. The segregated particles were thought to form a liquid phase alloy with aluminium during anodic polarization, which in turn, together with the chloride in the solution destabilized the oxide.

  9. Curie Temperature and Microstructural Changes Due to the Heating Treatment of Magnetic Amorphous Materials

    Directory of Open Access Journals (Sweden)

    Gondro J.

    2016-03-01

    Full Text Available Three distinct alloys: Fe86Zr7Nb1Cu1B5, Fe82Zr7Nb2Cu1B8, and Fe81Pt5Zr7Nb1Cu1B5 were characterized both magnetically and structurally. The samples, obtained with spinning roller method as a ribbons 3 mm in width and 20 μm thick, were investigated as-quenched and after each step of a multi steps heating treatment procedure. Each sample was annealed at four steps, fifteen minutes at every temperature, starting from 573K+600K up to +700K depending on type of alloy. Mössbauer spectroscopy data and transmission electron microscope (HRE M pictures confirmed that the as-quenched samples are fully amorphous. This is not changed after the first stages of treatment heating leads to a reduction of free volumes. The heating treatment has a great influence on the magnetic susceptibilities. The treatment up to 600K improves soft magnetic properties: an χ increase was observed, from about 400 to almost 1000 for the samples of alloys without Pt, and from about 200 to 450 at maximum, for the Fe81Pt5Zr7Nb1Cu1B5. Further heating, at more elevated temperatures, leads to magnetic hardening of the samples. Curie temperatures, established from the location of Hopkinson’s maxima on the χ(T curve are in very good agreement with those obtained from the data of specific magnetization, σ(T, measured in a field of 0.75T. As a critical parameter β was chosen to be equal 0.36 for these calculations, it confirmed that the alloys may be considered as ferromagnetic of Heisenberg type. Heating treatment resulted in decreasing of TC. These changes are within a range of several K.

  10. Heat Treatment of Buckypaper for Use in Volatile Organic Compounds Sampling

    Directory of Open Access Journals (Sweden)

    Jonghwa Oh

    2016-01-01

    Full Text Available Three types of buckypapers (BPs, two of them fabricated with arc discharge (AD single-walled carbon nanotubes (SWNTs (acetone-cleaned AD BP and methanol-cleaned AD BP and one with high-pressure carbon monoxide (HiPco SWNTs (HiPco BP, were heat-treated at different conditions to find the specific conditions for each type that improve the adsorption properties. Based on thermogravimetric analysis (TGA data, three heat treatment conditions were designed for the AD BPs and another three conditions for the HiPco BPs. Also, changes in weight and physical integrity before and after the heat treatment were considered. Heating at 300°C for 90 minutes was selected for acetone-cleaned AD BP, in which the BP kept its physical integrity and yielded a relatively high Brunauer, Emmett, and Teller (BET surface area (970 ± 18 m2/g, while methanol-cleaned AD BP was excluded because of its physical change. For HiPco BP, a condition of 300°C heating for 30 minutes was chosen as a relatively higher surface area (933 ± 54 m2/g and less weight loss (5% were observed.

  11. Quality of mango nectar processed by high-pressure homogenization with optimized heat treatment.

    Science.gov (United States)

    Tribst, Alline Artigiani Lima; Franchi, Mark Alexandrow; de Massaguer, Pilar Rodriguez; Cristianini, Marcelo

    2011-03-01

    This work aimed to evaluate the effect of high-pressure homogenization (HPH) with heat shock on Aspergillus niger, vitamin C, and color of mango nectar. The nectar was processed at 200 MPa followed by heat shock, which was optimized by response surface methodology by using mango nectar ratio (45 to 70), heat time (10 to 20), and temperature (60 to 85 °C) as variables. The color of mango nectar and vitamin C retention were evaluated at the optimized treatments, that is, 200 MPa + 61.5 °C/20 min or 73.5 °C/10 min. The mathematical model indicates that heat shock time and temperature showed a positive effect in the mould inactivation, whereas increasing ratio resulted in a protective effect on A. niger. The optimized treatments did not increase the retention of vitamin C, but had positive effect for the nectar color, in particular for samples treated at 200 MPa + 61.5 °C/20 min. The results obtained in this study show that the conidia can be inactivated by applying HPH with heat shock, particularly to apply HPH as an option to pasteurize fruit nectar for industries.

  12. PECULIARITIES OF GENERALIZATION OF SIMILAR PHENOMENA IN THE PROCESS OF FISH HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    V. A. Pokhol’chenko

    2015-01-01

    Full Text Available The theoretical presuppositions for the possibility of generalizing and similarity founding in dehydration and wet materials heating processes are studieded in this article. It is offered to carry out the given processes generalization by using dimensionless numbers of similarity. At the detailed analyzing of regularities of heat treatment processes of fish in different modes a significant amount of experienced material was successfully generalized on the basis of dimensionless simplex (similarity numbers. Using the dimensionless simplex allowed to detect a number of simple mathematical models for the studied phenomena. The generalized kinetic models of fish dehydration, the generalized dynamic models (changing moisture diffusion coefficients, the generalized kinetic models of fish heating (the temperature field changing in the products thickness, average volume and center were founded. These generalized mathematical models showed also relationship of dehydration and heating at the processes of fish semi-hot, hot smoking (drying and frying. The relationship of the results from the physical nature of the dehydration process, including a change in the binding energy of the moisture with the material to the extent of the process and the shrinkage impact on the rate of the product moisture removal is given in the article. The factors influencing the internal structure and properties of the raw material changing and retarding the dehydration processes are described there. There was a heating rate dependence of fish products on the chemical composition the geometric dimensions of the object of heating and on the coolant regime parameters. A unique opportunity is opened by using the generalized models, combined with empirically derived equations and the technique of engineering calculation of these processes, to design a rational modes of heat treatment of raw materials and to optimize the performance of thermal equipment.

  13. Effect of heat treatment on bend stress relaxation of pure tungsten

    International Nuclear Information System (INIS)

    Sasaki, Kenta; Nogami, Shuhei; Fukuda, Makoto; Katakai, Yasuyuki; Hasegawa, Akira

    2013-01-01

    Highlights: • Bend stress relaxation test was performed on the pure tungsten after heat treatment for stress relief. • The BSR ratio of the heat treated specimen was larger than that of the as-received specimen at this temperature region. • Small reduction in the BSR ratio was observed at the temperatures of 500–800 °C. • The BSR ratio of the heat treated specimen decreased significantly at the temperatures of 900–1000 °C. • The BSR ratio decreased significantly in a short time below 0.1 h, and then decreased slowly. -- Abstract: Bend stress relaxation (BSR) tests at temperatures of 500, 600, 800, 900 and 1000 °C for 0.1, 0.5 and 1 h in vacuum were performed on the pure tungsten after heat treatment for stress relief at 900 °C for 1 h. The degree of stress relaxation increased with test temperature. The BSR ratio of the heat treated specimen was larger than that of the as-received specimen at this temperature region. Small reduction in the BSR ratio was observed at the temperatures of 500, 600 and 800 °C. The BSR ratio of the heat treated specimen decreased significantly at the temperatures of 900 and 1000 °C and it was close to that of the as-received specimen. The BSR ratio of the heat treated specimen and the as-received specimen exhibited similar trend of time-evolution. The stress was exponentially relaxed with increasing test time. The BSR ratio decreased significantly in a short time below 0.1 h, and then decreased slowly. Higher activation energy of stress relaxation evaluated by cross-cut method was obtained for the higher temperature

  14. Proteomic Profiling Comparing the Effects of Different Heat Treatments on Camel (Camelus dromedarius) Milk Whey Proteins.

    Science.gov (United States)

    Benabdelkamel, Hicham; Masood, Afshan; Alanazi, Ibrahim O; Alzahrani, Dunia A; Alrabiah, Deema K; AlYahya, Sami A; Alfadda, Assim A

    2017-03-28

    Camel milk is consumed in the Middle East because of its high nutritional value. Traditional heating methods and the duration of heating affect the protein content and nutritional quality of the milk. We examined the denaturation of whey proteins in camel milk by assessing the effects of temperature on the whey protein profile at room temperature (RT), moderate heating at 63 °C, and at 98 °C, for 1 h. The qualitative and quantitative variations in the whey proteins before and after heat treatments were determined using quantitative 2D-difference in gel electrophoresis (DIGE)-mass spectrometry. Qualitative gel image analysis revealed a similar spot distribution between samples at RT and those heated at 63 °C, while the spot distribution between RT and samples heated at 98 °C differed. One hundred sixteen protein spots were determined to be significantly different ( p protein spots were decreased in common in both the heat-treated samples and an additional 25 spots were further decreased in the 98 °C sample. The proteins with decreased abundance included serum albumin, lactadherin, fibrinogen β and γ chain, lactotransferrin, active receptor type-2A, arginase-1, glutathione peroxidase-1 and, thiopurine S, etc. Eight protein spots were increased in common to both the samples when compared to RT and included α-lactalbumin, a glycosylation-dependent cell adhesion molecule. Whey proteins present in camel milk were less affected by heating at 63 °C than at 98 °C. This experimental study showed that denaturation increased significantly as the temperature increased from 63 to 98 °C.

  15. Effect of heat treatment regime on structural lamination in ferritic-austenitic steels

    International Nuclear Information System (INIS)

    Sizov, R.A.; Zakharova, M.I.; Novikov, I.I.; Bannykh, O.A.

    1983-01-01

    The effect of preliminary thermal treatment on lamination and viscosity of EhP-53 and KO-3 steels after durable aging at the temperature of 350 is studied. It is shown that preliminary heat treatment considerably affects lamination processes in the result of aging of 0Kh18G8N2T steel. The lowest rate of lamination and higher impact strength after aging at 350 deg C for 4500 hours corresponds to the following heat treatment: 10 hour aging at 650 deg C with cooling in the air, then quenching in water from 950 deg C after aging for 30 min and the following tempering (650 deg C, 5 hours). Unlike the 0Kh18G8N2T steel, lamination parameters of steel 0Kh22N6T practically do not change after the application of heat treatment. Nevertherless, taking into account results of impact strength, it is advisable to have thermal treatment according to the regime: quenching in water at 950 deg C after aging for 30 min

  16. Karakteristik Fisikokimia Mie Kering Berbasis Pati Ubi Jalar Varietas Lokal Dengan Menggunakan Metode Heat Moisture Treatment

    Directory of Open Access Journals (Sweden)

    Zaidiyah Zaidiyah

    2015-10-01

    Full Text Available The effects of heat moisture treatment (110°C and pretreatment on the physicochemical properties of sweet potato dried-noodles starch based were investigated. Completely randomized design was performed which arranged by two-factor. The first factor is noodles consist of native starch and treated starch (heat moisture treatment. The second factor is a type of sweet potato local varieties which consists of three levels: orange, purple and cream flesh color, respectively. Native starch and treated starch treatment showed significant effect on water content, protein and carbohydrate/fiber. Water absorption and cooking loss of dried noodle is highly different between native (non-HMT and treated starch (HMT.

  17. Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment.

    Directory of Open Access Journals (Sweden)

    Yang Qin

    Full Text Available Glutinous rice flour (GRF and glutinous rice starch (GRS were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05. Meanwhile, dry heating remarkably increased the apparent viscosities of both GRF and GRS. Importantly, compared with GRS samples, the storage modulus (G' and loss modulus (G" values of modified GRF increased more greatly and the tanδ values decreased more remarkably, indicating that the dry-heat treatment showed more impact on the GRF and a higher viscoelasticity compared with GRS. Our results suggest the dry-heat treatment of GRF is a more effective method than that of GRS, which omits the complex and tedious process for purifying GRS, and thereby has more practical applications in the food industry.

  18. Effect of heat treatment on carbon fiber surface properties and fibers/epoxy interfacial adhesion

    International Nuclear Information System (INIS)

    Dai Zhishuang; Zhang Baoyan; Shi Fenghui; Li Min; Zhang Zuoguang; Gu Yizhuo

    2011-01-01

    Carbon fiber surface properties are likely to change during the molding process of carbon fiber reinforced matrix composite, and these changes could affect the infiltration and adhesion between carbon fiber and resin. T300B fiber was heat treated referring to the curing process of high-performance carbon fiber reinforced epoxy matrix composites. By means of X-ray photoelectron spectroscopy (XPS), activated carbon atoms can be detected, which are defined as the carbon atoms conjunction with oxygen and nitrogen. Surface chemistry analysis shows that the content of activated carbon atoms on treated carbon fiber surface, especially those connect with the hydroxyl decreases with the increasing heat treatment temperature. Inverse gas chromatography (IGC) analysis reveals that the dispersive surface energy γ S d increases and the polar surface energy γ S sp decreases as the heat treatment temperature increases to 200. Contact angle between carbon fiber and epoxy E51 resin, which is studied by dynamic contact angle test (DCAT) increases with the increasing heat treatment temperature, indicating the worse wettability comparing with the untreated fiber. Moreover, micro-droplet test shows that the interfacial shear strength (IFSS) of the treated carbon fiber/epoxy is lower than that of the untreated T300B fiber which is attributed to the decrement of the content of reactive functional groups including hydrogen group and epoxy group.

  19. Microbial safety control of compost material with cow dung by heat treatment.

    Science.gov (United States)

    Gong, Chun-ming

    2007-01-01

    Various kinds of pathogenic bacteria derived from the intestinal tract of animals exist in compost material like cow dung. In order to sterilize the pathogenic bacteria completely in compost material, the cow dung was put into a heat treatment machine in pilot plan, and harmless condition in short time was examined. The results indicated, pathogenic indicator bacteria such as coliform bacteria, fecal coliform, Escherichia coli and salmonella were all 106 cfu/g dw at the beginning, died rapidly when cow dung temperature rose to above 50 degrees C, and not detected at 54-68 degrees C for 6-24 h heat treatment. Coliform bacteria and salmonella in heated cow dung were not detected by re-growth culture and enrichment culture examination. Moreover, it was hardly influenced on the fermentation ability of composting microbe, organic decomposition bacteria. During heat treatment, the mesophile decreased rapidly and the thermophile stabilized or increased, and the most of composting microbe were bacillus in cow dung by fluorescence microscope, this indicated that bacillus was dominator and composting microbe in composting process.

  20. Effect of grain orientation and heat treatment on mechanical properties of pure W

    Energy Technology Data Exchange (ETDEWEB)

    Noto, Hiroyuki, E-mail: noto_hiroyuki@iae.kyoto-u.ac.jp [Graduate School of Energy Science, Kyoto University, Kyoto 611-0011 (Japan); Research Fellow of Japan Society for the Promotion of Science (Japan); Taniguchi, Shuichi [Graduate School of Energy Science, Kyoto University, Kyoto 611-0011 (Japan); Kurishita, Hiroaki; Matsuo, Satoru [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Ukita, Takashi; Tokunaga, Kazutoshi [Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Kimura, Akihiko [Institute of Advanced Energy, Kyoto University, Kyoto 611-0011 (Japan)

    2014-12-15

    The effect of grain orientation, heat-treatment temperature and test temperature on the mechanical properties of tungsten (W), which vary depending on plastic working and fabrication process, was investigated by mechanical testing of tensile or bending. Heavily worked W samples (1.5–2.0 mm in the final thickness) exhibit degradation of fracture strength due to recrystallization embrittlement after heat-treatment at 1240 °C (temperature of diffusion bonding between W and a candidate material of the Fe base support structure). On the other hand, W samples with lower thickness reduction rates do not suffer degradation of fracture strength after heating up to around 1300 °C, and show somewhat higher fracture strength by heat-treatment below 1300 °C than the samples in the as-received state. The observed behavior is a reflection of recovery of dislocations introduced by plastic working. High temperature tensile testing of ITER grade W with an anisotropic grain structure and S-TUN with an equiaxed grain structure revealed that both W grades exhibit plastic elongation at temperatures higher than 200 °C with essentially the same temperature dependence of yield strength, which is relatively insensitive to grain orientation in the structure at 200–1300 °C.

  1. Effect of grain orientation and heat treatment on mechanical properties of pure W

    International Nuclear Information System (INIS)

    Noto, Hiroyuki; Taniguchi, Shuichi; Kurishita, Hiroaki; Matsuo, Satoru; Ukita, Takashi; Tokunaga, Kazutoshi; Kimura, Akihiko

    2014-01-01

    The effect of grain orientation, heat-treatment temperature and test temperature on the mechanical properties of tungsten (W), which vary depending on plastic working and fabrication process, was investigated by mechanical testing of tensile or bending. Heavily worked W samples (1.5–2.0 mm in the final thickness) exhibit degradation of fracture strength due to recrystallization embrittlement after heat-treatment at 1240 °C (temperature of diffusion bonding between W and a candidate material of the Fe base support structure). On the other hand, W samples with lower thickness reduction rates do not suffer degradation of fracture strength after heating up to around 1300 °C, and show somewhat higher fracture strength by heat-treatment below 1300 °C than the samples in the as-received state. The observed behavior is a reflection of recovery of dislocations introduced by plastic working. High temperature tensile testing of ITER grade W with an anisotropic grain structure and S-TUN with an equiaxed grain structure revealed that both W grades exhibit plastic elongation at temperatures higher than 200 °C with essentially the same temperature dependence of yield strength, which is relatively insensitive to grain orientation in the structure at 200–1300 °C

  2. Surface chemistry of polyacrylonitrile- and rayon-based activated carbon fibers after post-heat treatment

    International Nuclear Information System (INIS)

    Chiang Yuchun; Lee, C.-Y.; Lee, H.-C.

    2007-01-01

    Polyacrylonitrile- and rayon-based activated carbon fibers (ACFs) subject to heat treatment were investigated by means of elemental analyzer, and X-ray photoelectron spectroscopy (XPS). The total ash content of all ACFs was also analyzed. The adsorption of benzene, carbon tetrachloride and water vapor on ACFs was determined to shed light on the role of surface chemistry on gas adsorption. Results show that different precursors resulted in various elemental compositions and imposed diverse influence upon surface functionalities after heat treatment. The surface of heat-treated ACFs became more graphitic and hydrophobic. Three distinct peaks due to C, N, and O atoms were identified by XPS, and the high-resolution revealed the existence of several surface functionalities. The presence of nitride-like species, aromatic N-imines, or chemisorbed nitrogen oxides was found to be of great advantage to adsorption of water vapor or benzene, but the pyridine-N was not. Unstable complexes on the surface would hinder the fibers from adsorption of carbon tetrachloride. The rise in total ash content or hydrogen composition was of benefit to the access of water vapor. Modifications of ACFs by heat treatment have effectively improved adsorption performance

  3. Heat treatment of TI-6AL-4V produced by lasercusing

    Directory of Open Access Journals (Sweden)

    Becker, Thorsten

    2015-08-01

    Full Text Available LaserCUSING® is a selective laser melting (SLM process that is capable of manufacturing parts by melting powder with heat input from a laser beam. LaserCUSING demonstrates potential for producing the intricate geometries specifically required for biomedical implants and aerospace applications. One main limitation to this form of rapid prototyping is the lack of published studies on the material performance of the resulting material. Studies of the material’s performance are often complicated by dependence on several factors, including starting powder properties, laser parameters, and post-processing heat treatments. This study aims to investigate the mechanical properties of LaserCUSING-produced Ti-6Al-4V and its performance relative to the conventional wrought counterpart. A combination of conventional and LaserCUSING-tailored heat treatments is performed. The resulting microstructures are studied and linked to the properties obtained from hardness tests. The findings highlight that LaserCused Ti-6Al-4V is competitive with traditional materials, provided that optimal parameters are chosen and parts are subject to tailored post-processing. In the as-built condition, LaserCused Ti-6Al-4V displays superior strength and hardness as a result of a martensitic microstructure, and a poorer performance in ductility. However, the material performance can be improved using tailored heat treatments. Careful consideration must be given to suitable post-processing before application in critical components in the aerospace or biomedical industry can occur

  4. Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment.

    Science.gov (United States)

    Qin, Yang; Liu, Chengzhen; Jiang, Suisui; Cao, Jinmiao; Xiong, Liu; Sun, Qingjie

    2016-01-01

    Glutinous rice flour (GRF) and glutinous rice starch (GRS) were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05). Meanwhile, dry heating remarkably increased the apparent viscosities of both GRF and GRS. Importantly, compared with GRS samples, the storage modulus (G') and loss modulus (G") values of modified GRF increased more greatly and the tanδ values decreased more remarkably, indicating that the dry-heat treatment showed more impact on the GRF and a higher viscoelasticity compared with GRS. Our results suggest the dry-heat treatment of GRF is a more effective method than that of GRS, which omits the complex and tedious process for purifying GRS, and thereby has more practical applications in the food industry.

  5. Computerized property prediction and process planning in heat treatment of steels

    Energy Technology Data Exchange (ETDEWEB)

    Gergely, M. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Somogyi, S. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Kohlheb, R. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary))

    1994-01-01

    Recent years have seen widespread interest in the establishment of prediction methods, based on phenomenological description and computer simulation of transformation processes during heat treatment, and in the introduction of software for technological planning. The steady development of this approach is aimed at meeting the requirement of metallurgists, design engineers dealing with material selection and dimensioning, and technologists planning heat treatment processes. Research in this field of computer simulation has been concentrated so far on two main areas of interest: . Modelling of transformation processes and the prediction of microstructures and/or properties, . Developing program packages to help solve concrete tasks such as material selection, on-line process control and monitoring, and the design of heat-treating operations. During the last two decades in the field of heat treatment, various mathematical models with different accuracy and complexity have been developed. In this paper, an attempt is made to outline some important results in computer simulation and computerized property prediction without aiming at completeness. The topic is restricted to quenched and tempered, and case-hardened steels. (orig.)

  6. 3D numerical modeling of coupled phenomena in induced processes of heat treatment with malice

    Directory of Open Access Journals (Sweden)

    Triwong Peeteenut

    2008-01-01

    Full Text Available This paper describes a multi-method Malice package for three dimension coupled phenomena in induced processes of heat treatment by an algorithm weakly coupled with the Migen package integral method defining the electromagnetic model and the Flux-Expert package finite element method defining the thermal model. The integral method is well suited to inductive systems undergoing sinusoidal excitation at midrange or high frequency. The unknowns of both models are current density, scalar potential and temperature. Joule power in the electromagnetic model is generated by Eddy currents. It becomes the heat source in the thermal model.

  7. Mechanical and microstructural characterization of the nickel base alloy (Alloy 600) after heat treatment

    International Nuclear Information System (INIS)

    Fernandes, Stela Maria de Carvalho

    1993-01-01

    The characterization of microstructural and mechanical properties of cold rolled and heat treated alloys 600 made in Brazil were investigated. The recovery and recrystallization behavior as well as solubilization and aging have been studied using optical, scanning electron and transmission electron microscopy. Microhardness and tensile testing have been carried out. The recovery process of the cold rolled alloy 600 occurred until 600 deg C and the recrystallization stage was situated between 600 and 850 deg C. The primary recrystallization temperature was obtained at 850 deg C after 1 hour (isochronal heat treatments). The aged alloy 600 shows carbide precipitation on grains bu with ductility maintenance. (author)

  8. Effect of Heat Treatment on the Hardness and Wear of Grinding Balls

    Science.gov (United States)

    Aissat, Sahraoui; Sadeddine, Abdelhamid; Bradai, Mohand Amokrane; Younes, Rassim; Bilek, Ali; Benabbas, Abderrahim

    2017-09-01

    The effect quenching and tempering by different regimes on Rockwell hardness and wear processes of grinding balls 50 and 70 mm in diameter made of two melts of chromium-molybdenum cast iron is studied. The heating temperature for quenching is 850, 950, and 1050°C; the tempering temperature is 250, 400, and 600°C. Iron is analyzed in an electron microscope. Diffraction patterns are obtained. A model of cast iron wear is suggested and compared to the Davis model and to experimental results. An optimum heat treatment regime is proposed.

  9. Influence of the chemical composition, heat and surface treatment in the biofouling of austenitic stainless steels

    International Nuclear Information System (INIS)

    Sarro, M. I.; Aleman, O.; Moreno, D. A.; Roso, M.; Ranninger, C.

    2004-01-01

    The main objective of this study was to analyse the biofouling processes in the kinds of stainless steels used normally in industry (UNS S30400, UNS S30403 and UNS S31600), with different surface treatments after grinding and polishing. The study was developed using two microscopy techniques. Scanning Electron Microscopy (SEM was used to evaluate the microorganisms distribution in the materials, and Epi fluorescence Microscopy was used to evaluate the viability of cells in the biofilm. The results revealed the influence of the material, heat treatment, surface treatment and roughness in the biofouling processes in the stainless steel assays. (Author) 33 refs

  10. The influence of heat treatments on several types of base-metal removable partial denture alloys.

    Science.gov (United States)

    Morris, H F; Asgar, K; Rowe, A P; Nasjleti, C E

    1979-04-01

    Four removable partial denture alloys, Vitallium (Co-Cr alloy), Dentillium P.D. (Fe-Cr alloy), Durallium L.G. (Co-Cr-Ni alloy), and Ticonium 100 (Ni-Cr alloy), were evaluated in the as-cast condition and after heat treatment for 15 minutes at 1,300 degrees, 1,600 degrees, 1,900 degrees, and 2,200 degrees F followed by quenching in water. The following properties were determined and compared for each alloy at each heat treatment condition: the yield strengths at 0.01%, 0.1%, and 0.2% offsets, the ultimate tensile strength, the percent elongation, the modulus of elasticity, and the Knoop microhardness. The results were statistically analyzed. Photomicrographs were examined for each alloy and test condition. The following conclusions were made: 1. The "highest values" were exhibited by the as-cast alloy. 2. Heat treatment of the partial denture alloys tested resulted in reductions in strength, while the elongations varied. This study demonstrates that, in practice, one should avoid (a) prolonged "heat-soaking" while soldering and (b) grinding or polishing of the casting until the alloy is "red hot". 3. Durallium L.G. was the least affected by the various heat treatment conditions. 4. Conventional reporting of the yield strength at 0.2% offset, the ultimate tensile strength, and percent elongation are not adequate to completely describe and compare the mechanical behavior of alloys. The reporting of the yield strength at 0.01% offset, in addition to the other reported properties, will provide a more complete description of the behavior of the dental alloys.

  11. Influence of prolonged storage process, pasteurization, and heat treatment on biologically-active human milk proteins.

    Science.gov (United States)

    Chang, Jih-Chin; Chen, Chao-Huei; Fang, Li-Jung; Tsai, Chi-Ren; Chang, Yu-Chuan; Wang, Teh-Ming

    2013-12-01

    The bioactive proteins in human milk may be influenced by prolonged storage process, pasteurization, and heat treatment. This study was conducted to evaluate the effects of these procedures. Three forms of human milk - freshly expressed, frozen at -20°C for a prolonged duration, and pasteurized milk - were collected from 14 healthy lactating mothers and a milk bank. The concentrations of major bioactive proteins (secretory immunoglobulin A, lactoferrin, lysozyme, and leptin) were quantified using enzyme-linked immunosorbent assay kits. Changes in these proteins by heat treatment at 40°C or 60°C for 30 minutes were further evaluated. The mean concentrations of lactoferrin and secretory immunoglobulin A were significantly reduced by 66% and 25.9%, respectively, in pasteurized milk compared with those in freshly-expressed milk. Heat treatment at 40°C or 60°C did not cause significant changes in lactoferrin and secretory immunoglobulin A, but there was an apparent increase in lysozyme (p = 0.016). There were no significant differences in leptin level among these three forms of milk prior to (p = 0.153) or after heat treatment (p = 0.053). Various freezing/heating/pasteurization processes applied to human milk prior to delivery to neonates could affect the concentration of immunomodulatory proteins, especially lactoferrin, secretory immunoglobulin A, and lysozyme. Leptin was unaffected by the various handling processes tested. Fresh milk was found to be the best food for neonates. Further studies are warranted to evaluate the functional activity of these proteins and their effects on infants' immunological status. Copyright © 2013. Published by Elsevier B.V.

  12. Effect of tin oxide nano particles and heat treatment on decay resistance and physical properties of beech wood (Fagus orientalis

    Directory of Open Access Journals (Sweden)

    Maryam Ghorbani

    2014-11-01

    Full Text Available This research was conducted to investigate the effect of Tin oxide nanoparticles and heat treatment on decay resistance and physical properties of beech wood. Biological and physical test samples were prepared according to EN-113 and ASTM-D4446-05 standards respectively. Samples were classified into 4 groups: control, impregnation with Tin oxide nanoparticles, heat treatment and nano-heat treatment. Impregnation with Tin oxide nano at 5000ppm concentration was carried out in the cylinder according to Bethell method. Then, samples were heated at 140, 160 and 185˚C for 2 and 4 hours. According to results, decay resistance improved with increasing time and temperature of heat treatment. Least weight loss showed 46.39% reduction in nano-heat samples treated at 180˚C for 4 hours in comparison with control at highest weight loss. Nano-heat treated samples demonstrated the maximum amount of water absorption without significant difference with control and nanoparticles treated samples. Increase in heat treatment temperature reduced water absorption so that it is revealed 47.8% reduction in heat treated samples at 180°C for 4h after 24h immersion in water. In nano-heat treated samples at 180˚C for 2h was measured least volume swelling. Volume swelling in nano-treated samples decreased 8.7 and 22.76% after 2 and 24 h immersion in comparison with the control samples respectively.

  13. Nonlinear dynamics of spring softening and hardening in folded-mems comb drive resonators

    KAUST Repository

    Elshurafa, Amro M.; Khirallah, Kareem; Tawfik, Hani H.; Emira, Ahmed; Abdel Aziz, Ahmed K S; Sedky, Sherif M.

    2011-01-01

    This paper studies analytically and numerically the spring softening and hardening phenomena that occur in electrostatically actuated microelectromechanical systems comb drive resonators utilizing folded suspension beams. An analytical expression

  14. Acoustic softening in metals during ultrasonic assisted deformation via CP-FEM

    KAUST Repository

    Siddiq, Amir; El Sayed, Tamer S.

    2011-01-01

    In this paper, a phenomenological crystal plasticity model is modified to account for acoustic (ultrasonic) softening effects based on the level of ultrasonic intensity supplied to single and polycrystalline metals. The material parameters

  15. Effect of Heat Treatment on the Structure and Properties of Die Steel 70Kh3G2FTR

    Science.gov (United States)

    Krylova, S. E.; Kletsova, O. A.; Gryzunov, V. I.; Fot, A. P.; Tavtilov, I. Sh.

    2018-01-01

    The effect of heat treatment parameters on the properties and structural and phase composition of a promising die steel 70Kh3G2FTR for hot deformation is studied. The temperature-and-stress state of a hammer die under a heat treatment is simulated.

  16. Effects of post heat-treatment on surface characteristics and adhesive bonding performance of medium density fiberboard

    Science.gov (United States)

    Nadir Ayrilimis; Jerrold E. Winandy

    2009-01-01

    A series of commercially manufactured medium density fiberboard (MDF) panels were exposed to a post-manufacture heat-treatment at various temperatures and durations using a hot press and just enough pressure to ensure firm contact between the panel and the press platens. Post-manufacture heat-treatment improved surface roughness of the exterior MDF panels. Panels...

  17. 热处理与可持续发展%Heat Treatment and Sustainable Development

    Institute of Scientific and Technical Information of China (English)

    徐跃明; 樊东黎

    2001-01-01

    In the view point of sustainable development,there exist some serious problems,such as higher energy consumption,environmental pollution,oxidation and decarburization of steels,in the heat treatment industry of China.In order to keep the sustainable development of heat treatment industry in China,something must be done.First of all is to heighten sustainable development consciousness.At the same time,it is necessary to strengthen technology innovation and speed up improving traditional heat treatment industry with high technology,to develop the clean production of heat treatment and popularize the application of efficient,energy saving and none or less oxidation heat treatment technology.A great attention is still paid to the certification of ISO9000 and ISO14000 series standard and heat treatment industry standard to raise modernized and standard management level of enterprises.%从可持续发展的角度分析,我国热处理行业主要存在能耗高、环境污染严重、氧化脱碳严重3大问题。目前,热处理行业仍普遍存在节能环保意识不强,缺乏有效的管理措施,技术落后等现象。面对新的挑战,热处理要在21世纪得到持续发展,必须从“源消减”做起。首先要加强可持续发展的意识;加强技术创新,加快用高新技术改造传统热处理产业的步伐;积极发展热处理清洁生产,推广高效、节能、少无氧化热处理技术;重视ISO9000、ISO14000标准系列认证和行业达标验收工作,全面提高企业现代化、规范化管理水平。

  18. Optimization of hardening/softening behavior of plane frame structures using nonlinear normal modes

    DEFF Research Database (Denmark)

    Dou, Suguang; Jensen, Jakob Søndergaard

    2016-01-01

    Devices that exploit essential nonlinear behavior such as hardening/softening and inter-modal coupling effects are increasingly used in engineering and fundamental studies. Based on nonlinear normal modes, we present a gradient-based structural optimization method for tailoring the hardening...... involving plane frame structures where the hardening/softening behavior is qualitatively and quantitatively tuned by simple changes in the geometry of the structures....

  19. HEAT TREATMENTS OF HIGH TEMPERATURE DRIED NORWAY SPRUCE BOARDS: SACCHARIDES AND FURFURALS IN SAPWOOD SURFACES

    Directory of Open Access Journals (Sweden)

    Olov Karlsson,

    2012-02-01

    Full Text Available Carbohydrates that migrate to wood surfaces in sapwood during drying might influence properties such as mould susceptibility and colour. Sugars on the surface of Norway spruce boards during various heat treatments were studied. Samples (350mmx125mmx25mm were double-stacked, facing sapwood-side outwards, and dried at 110oC to a target moisture content (MC of 40%. Dried sub-samples (80 mm x 125 mm x 25 mm were stacked in a similar way and further heated at 110oC and at 130oC for 12, 24, and 36 hours, respectively. Glucose, fructose, and sucrose as well as 5-hydroxymethylfurfural (HMF and furfural in the sapwood surface layer of treated wood were analysed using HPLC (RI- and UV-detectors. Carbohydrates degraded to a lower extent at 110oC than at 130oC. Furfural and to a larger extent HMF increased with treatment period and temperature. Heat treatment led to a decrease in lightness and hue of the sapwood surface of sub-samples, while chroma increased somewhat. Furthermore, considerably faster degradation (within a few minutes of the carbohydrates on the surface of the dried spruce boards was observed when single sub-samples were conductively hot pressed at 200oC. Treatment period and initial MC influenced the presence of the carbohydrates in wood surface as well as colour change (Eab of the hot pressed sub-samples.

  20. Heat treatment effect on the texture and mechanical properties of the VT14 alloy cylinders

    International Nuclear Information System (INIS)

    Betsofen, S.Ya.; Khorev, A.I.; Babarehko, A.A.; Krasnozhon, A.I.; Kadobnova, N.V.

    1978-01-01

    The mechanical properties and the texture of cylinders made of VT14 alloy in the conditions after quenching from the temperature of 880 deg C, followed by ageing for 16 hours at the temperature of about 480 deg C, or after 20 minutes annealing at the temperature of 750 deg C, were stu--died, while taking into account the influence of intermediate preheats up to 800-1000 deg C prior to carrying into effect those kinds of heat treatment. It is shown that the texture of cylinders after heat treatment without the intermediate preheats prior to quenching is characterized by an increased density of poles in the axial and tangential directions. It is the preheating up to 1000 deg C prior to quenching that shifts the texture maxima in the axial direction and causes the appearance of component (0001). Under the effect of the intermediate preheating up to 1000 deg C, the biaxial and monoaxial strength of the cylinders decreases, whereas their tendency to brittle failure increases. The mechanical strength of all the thermally hardened cylinders, independently of the intermediate treatment, is in the tangential direction higher than in the axial direction. The proportions of the structure and texture factors have been assessed in the variation of the structural strength of the cylinders during the course of their heat treatment

  1. Phase transformation and hardness of SS 316 L steel cast alloy after heat treatment at high temperature

    International Nuclear Information System (INIS)

    Hidayat, S.; Prayitno, D. H.

    2000-01-01

    Heat treatment Study of SS 316 L cast alloy at high temperature was conducted. The alloy of SS 316 L was melted by arc melting furnace in argon atmosphere. Heat treatment of SS 316 L casting alloy was carried out in tube furnace at 1400 o C for period of 1/2, 1, and 2 hours. The optical microscopic characterization showed that SS 316 L cast has got dendritic micro structure with ferrite as the primary phase. After the heat treatment, the ferrite phase underwent gradual decrease followed by an increase of the austenite phase. The heat treatment process also resulted in the formation of the new grain boundary. The hardness examination revealed that for longer period of the heat treatment, the hardness of SS 316 L increased. (author)

  2. Characterization by transmission electron microscopy of a JRQ steel subjected to different heat treatments

    International Nuclear Information System (INIS)

    Moreno G, N.

    2014-01-01

    In this work a study was conducted on the steel Astm A-533, Grade B, Class 1 of reference JRQ, for the purpose of carrying out a study by transmission electron microscopy on the size and distribution of precipitates in steel samples JRQ previously subjected to heat treatments. This because the reactor vessels of the nuclear power plant of Laguna Verde, are made of a steel Astm A-533 Grade B, Class 1. It is known that the neutron radiation causes damage primarily embrittlement in materials that are exposed to it. However, observable damage through mechanical tests result from microstructural defects and atomic, induced by the neutron radiation. In previous studies hardening by precipitation of a JRQ steel (provided by the IAEA) was induced by heat treatments, finding that the conditions of heat treatment that reproduce the hardness and stress mechanical properties of a steel Astm A-533, Grade B, Class 1 irradiated for 8 years to a fluence of 3.5 x 10 17 neutrons/cm 2 and to a temperature of 290 grades C are achieved with annealing treatments at 550 grades C. In the studied samples it was found that the more hardening phase both the heat treatments as the neutron radiation, is the bainite, being the ferrite practically unchanged. Which it gave the tone to believe that the ferrite is the phase that provides at level macro the mechanical properties in stress, since in the irradiated samples such properties remained unchanged with respect to the non-irradiated material, however changes were observed in material ductility, which may be attributable to the change of hardness in the bainite, which opens a possibility for modeling the micromechanical behavior of this material. (Author)

  3. Degradation of Anthocyanin Content in Sour Cherry Juice During Heat Treatment

    Directory of Open Access Journals (Sweden)

    Lilla Szalóki-Dorkó

    2015-01-01

    Full Text Available Sour cherry juices made from two sour cherry cultivars (Érdi bőtermő and Kántorjánosi 3, were investigated to determine their total anthocyanin content and half-life of anthocyanins during heat treatment at different temperatures (70, 80 and 90 °C for 4 h. Before the heat treatment, Érdi bőtermő juice had higher anthocyanin concentration (812 mg/L than Kántorjánosi 3 juice (513 mg/L. The greatest heat sensitivity of anthocyanins was measured at 90 °C, while the treatments at 80 and 70 °C caused lower thermal degradation. The loss of anthocyanins in Érdi bőtermő juice after treatment was 38, 29 and 18 %, respectively, while in Kántorjánosi 3 juice losses of 46, 29 and 19 % were observed, respectively. At 90 °C sour cherry Érdi bőtermő juice had higher half-life (t1/2 of anthocyanins, while the Kántorjánosi 3 juice had higher t1/2 values at 70 °C. Cyanidin-3-glucosyl-rutinoside was present in higher concentrations in both cultivars (Érdi bőtermő: 348 and Kántorjánosi 3: 200 mg/L than cyanidin-3-rutinoside (177 and 121 mg/L before treatment. However, during the experiment, cyanidin-3-rutinoside was proved to be more resistant to heat. Comparing the two varieties, both investigated pigment compounds were more stable in Kántorjánosi 3 than in Érdi bőtermő. Degradation rate of anthocyanins was cultivar-dependent characteristic, which should be taken into account in the food production.

  4. Non-lethal heat treatment of cells results in reduction of tumor initiation and metastatic potential

    International Nuclear Information System (INIS)

    Kim, Yoo-Shin; Lee, Tae Hoon; O'Neill, Brian E.

    2015-01-01

    Non-lethal hyperthermia is used clinically as adjuvant treatment to radiation, with mixed results. Denaturation of protein during hyperthermia treatment is expected to synergize with radiation damage to cause cell cycle arrest and apoptosis. Alternatively, hyperthermia is known to cause tissue level changes in blood flow, increasing the oxygenation and radiosensitivity of often hypoxic tumors. In this study, we elucidate a third possibility, that hyperthermia alters cellular adhesion and mechanotransduction, with particular impact on the cancer stem cell population. We demonstrate that cell heating results in a robust but temporary loss of cancer cell aggressiveness and metastatic potential in mouse models. In vitro, this heating results in a temporary loss in cell mobility, adhesion, and proliferation. Our hypothesis is that the loss of cellular adhesion results in suppression of cancer stem cells and loss of tumor virulence and metastatic potential. Our study suggests that the metastatic potential of cancer is particularly reduced by the effects of heat on cellular adhesion and mechanotransduction. If true, this could help explain both the successes and failures of clinical hyperthermia, and suggest ways to target treatments to those who would most benefit. - Highlights: • Non-lethal hyperthermia treatment of cancer cells is shown to cause a reduction in rates of tumor initiation and metastasis. • Dynamic imaging of cells during heat treatment shows temporary changes in cell shape, cell migration, and cell proliferation. • Loss of adhesion may lead to the observed effect, which may disproportionately impact the tumor initiating cell fraction. • Loss or suppression of the tumor initiating cell fraction results in the observed loss of metastatic potential in vivo. • This result may lead to new approaches to synergizing hyperthermia with surgery, radiation, and chemotherapy

  5. Non-lethal heat treatment of cells results in reduction of tumor initiation and metastatic potential

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoo-Shin; Lee, Tae Hoon; O' Neill, Brian E., E-mail: BEOneill@houstonmethodist.org

    2015-08-14

    Non-lethal hyperthermia is used clinically as adjuvant treatment to radiation, with mixed results. Denaturation of protein during hyperthermia treatment is expected to synergize with radiation damage to cause cell cycle arrest and apoptosis. Alternatively, hyperthermia is known to cause tissue level changes in blood flow, increasing the oxygenation and radiosensitivity of often hypoxic tumors. In this study, we elucidate a third possibility, that hyperthermia alters cellular adhesion and mechanotransduction, with particular impact on the cancer stem cell population. We demonstrate that cell heating results in a robust but temporary loss of cancer cell aggressiveness and metastatic potential in mouse models. In vitro, this heating results in a temporary loss in cell mobility, adhesion, and proliferation. Our hypothesis is that the loss of cellular adhesion results in suppression of cancer stem cells and loss of tumor virulence and metastatic potential. Our study suggests that the metastatic potential of cancer is particularly reduced by the effects of heat on cellular adhesion and mechanotransduction. If true, this could help explain both the successes and failures of clinical hyperthermia, and suggest ways to target treatments to those who would most benefit. - Highlights: • Non-lethal hyperthermia treatment of cancer cells is shown to cause a reduction in rates of tumor initiation and metastasis. • Dynamic imaging of cells during heat treatment shows temporary changes in cell shape, cell migration, and cell proliferation. • Loss of adhesion may lead to the observed effect, which may disproportionately impact the tumor initiating cell fraction. • Loss or suppression of the tumor initiating cell fraction results in the observed loss of metastatic potential in vivo. • This result may lead to new approaches to synergizing hyperthermia with surgery, radiation, and chemotherapy.

  6. Heat treatment on keruing and light red meranti: The effect of heat exposure at different levels of temperature on bending strength properties

    Science.gov (United States)

    Noh, Nur Ilya Farhana Md; Ahmad, Zakiah

    2017-11-01

    Heat treatment on timbers is a process of applying heat to modify and equip the timbers with new improvised characteristics. It is environmental friendly compared to the common practice of treating timber by chemical preservatives. Malaysian hardwood timbers namely Keruing and Light Red Meranti which are in green condition were heat treated at temperature 150°C, 170°C, 190°C and 210°C, in a specially designed electronic furnace within one hour duration. The objectives were to determine the effect of heat treatment on bending strength properties of heat treated timbers in terms of Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) and to examine the significance changes at each temperature level. Untreated samples for each species were used as a control sample. The results indicated that the bending strength properties for both species of timbers were affected by the heat exposure. Both MOE and MOR values for heat treated Keruing were increased when subjected to the temperature levels at 150°C, 170°C and 190°C except at 210°C. Heat treated Light Red Meranti shows the same pattern of increment on its MOE and MOR values after exposure to heat at three temperature levels applied and the values dropped at 210°C. However, for both of species, even though there were decrement occurred at 210°C, the value is still higher compared to the control sample. The increments of MOE and MOR values are an indicator that heat treatment had successfully improvised the bending strength properties of these two species of hardwood timber.

  7. Heat treatments and low temperature fracture toughness of a Ti-6A1-4V alloy

    International Nuclear Information System (INIS)

    Nagai, K.; Hiraga, K.; Ishikawa, K.; Ogata, T.

    1984-01-01

    Titanium alloy is one of the reliable structural materials for cryogenic use owing to its high strength, high specific strength and low thermal conductivity. Heat treatment is one method of controlling the normally poor fracture toughness of this alloy at ambient temperature. However, there have been few attempts to improve the low temperature fracture toughness by heat treatment. This study was conducted to elucidate the effects of heat treatments on the low temperature fracture toughness in a Ti-6A1-4V alloy. The effects of the heat treatments were as follows: the beta treatment was a very feasible method to improve the low temperature fracture properties; the alpha+beta treatment was favorable for the increment in the low temperature ductility but did not largely improve the fracture toughness; the double treatment yielded good ductility but was not useful for improving the fracture toughness

  8. Effect of nitrite on the microbiological stability of canned Vienna sausages preserved by mild heat treatment or combinations of heat and irradiation

    International Nuclear Information System (INIS)

    Farkas, J.; Zukal, E.; Incze, K.

    1973-01-01

    Keeping quality of Vienna sausages packed in No. 1/5 cans (ca 200 g) with salt brine and heat treated with F 0 values in the range of 0.25-0.55 was studied as a function of sodium nitrate addition. In uninoculated cans the heat requirement of preservation proved to be about 0.3 F 0 in the presence of 300 ppm NaNO 2 . A heat treatment of 0.55 F 0 and 200 ppm NaNO 2 resulted in higher microbiological stability of cans inoculated with 2x10 4 /tin Clostridium sporogenes spores than a heat treatment of 1.9 F 0 without nitrite addition. The effect of the combination of heat treatment of 0.35-0.55 F 0 and 0.45 Mrad of gamma irradiation was also studied with inoculated cans. The combination of irradiation plus heat resulted in a higher microbiological stability of the samples than the reversed order of the treatments, but this synergistic effect could not be proved in all experiments. The addition of 200 ppm NaNO 2 was not as effective in increasing the shelf-life of combination treated samples as with the solely heat treated ones. In a medium composed of a 50% extract of Vienna sausages (pH 6.4, asub(w) 0.96) and inoculated with 10 5 per ml Clostridium sporogenes spores 100 ppm or more NaNO 2 was required to ensure microbiological stability of samples heat treated with F 0 0.4. In the range of the permitted concentration level for canned meat products, sodium nitrite did not influence the heat resistance of Clostridium sporogenes, but inhibited the germination of the surviving spores. (F.J.)

  9. Cost-benefit analysis of central softening for production of drinking water.

    Science.gov (United States)

    Van der Bruggen, B; Goossens, H; Everard, P A; Stemgée, K; Rogge, W

    2009-01-01

    Softening drinking water before distribution yields advantages with environmental impact, such as lower household products consumption, less scaling in piping and machines, and the avoidance of decentralized, domestic softeners. Central softening is under consideration in Flanders by the largest water supplier, VMW (Dutch acronym for "Flemish Company for Water Supply"), to deliver soft (15 degrees F) water to their customers. A case study is presented for a region with hard water (47 degrees F). The chosen technique is the pellet reactor, based on precipitation of CaCO(3) by NaOH addition. This softening operation has possibly large impact on the environment and the water consumption pattern. A cost-benefit analysis has been made to estimate the added value of central softening, by investigating the impact on the drinking water company, on their customers, on employment, on environment, on health, etc. The analysis for the region of study revealed benefits for customers which were higher than the costs for the drinking water company. However, pricing of drinking water remains an important problem. A sensitivity analysis of these results has also been made, to evaluate the impact of important hypothesis, and to be able to expand this study to other regions. The conclusions for this part show that softening is beneficial if water hardness is to be decreased by at least 5 degrees F.

  10. Aesthetic value improvement of the ruby stone using heat treatment and its synergetic surface study

    International Nuclear Information System (INIS)

    Sahoo, Rakesh K.; Mohapatra, Birendra K.; Singh, Saroj K.; Mishra, Barada K.

    2015-01-01

    Highlights: • Natural ruby is heated at high temperature with metal oxide additives (PbO and ZnO) to enhance its aesthetic value. • Changes in surface characteristics of these natural rubies before and after heat treatment are compared. • The R-line peak splitting in the PL spectra and the contrary shift of the Al 2p peaks in the XPS spectra are explicated. - Abstract: The surface behavior of the natural ruby stones before and after heat treatment with metal oxide additives like: zinc oxide (ZnO) and lead oxide (PbO) have been studied. The surface appearance of the ruby stones processed with the metal oxides changed whereas the bulk densities of the stones remained within the range of 3.9–4.0 g/cm 3 . The cracks healing and pores filling by the metal oxides on the surface of the ruby have been examined using scanning electron microscopy. The chemical compositions based on the XPS survey scans are in good agreement with the expected composition. The phase and crystallinity of the ruby stones original and heat-treated were obtained from their X-ray diffraction patterns. The change in peak separation between R 1 and R 2 – peaks in photoluminescence spectra and the contrary binding energy shift of the Al 2p peaks in the X-ray photoelectron spectra have been explicated. Moreover, in this work we describe the change in surface chemical and physical characteristics of the ruby stone before and after heat treatment

  11. Effects of Heating Rate on the Dynamic Tensile Mechanical Properties of Coal Sandstone during Thermal Treatment

    Directory of Open Access Journals (Sweden)

    Ming Li

    2017-01-01

    Full Text Available The effects of coal layered combustion and the heat injection rate on adjacent rock were examined in the process of underground coal gasification and coal-bed methane mining. Dynamic Brazilian disk tests were conducted on coal sandstone at 800°C and slow cooling from different heating rates by means of a Split Hopkinson Pressure Bar (SHPB test system. It was discovered that thermal conditions had significant effects on the physical and mechanical properties of the sandstone including longitudinal wave velocity, density, and dynamic linear tensile strength; as the heating rates increased, the thermal expansion of the sandstone was enhanced and the damage degree increased. Compared with sandstone at ambient temperature, the fracture process of heat-treated sandstone was more complicated. After thermal treatment, the specimen had a large crack in the center and cracks on both sides caused by loading; the original cracks grew and mineral particle cracks, internal pore geometry, and other defects gradually appeared. With increasing heating rates, the microscopic fracture mode transformed from ductile fracture to subbrittle fracture. It was concluded that changes in the macroscopic mechanical properties of the sandstone were result from changes in the composition and microstructure.

  12. Changes in protein and starch digestibility in sorghum flour during heat-moisture treatments.

    Science.gov (United States)

    Vu, Thanh-Hien; Bean, Scott; Hsieh, Chao-Feng; Shi, Yong-Cheng

    2017-11-01

    Heat-moisture treatment (HMT) has been used to modify properties of sorghum starches. However, information is limited on the effects of HMT on the digestibility of starch and the concurrent changes in protein in sorghum flour. The objectives of this research were to identify heat-moisture conditions to increase the resistant starch (RS) content of sorghum flour and investigate changes in sorghum proteins and starch structure. Sorghum flours with different moisture contents (0, 125, 200, and 300 g kg -1 w.b.) were heated at three temperatures (100, 120 and 140 °C) and times (1, 2 and 4 h). HMT of sorghum flour increased its RS level. The flour treated at 200 g kg -1 moisture and 100 °C for 4 h had a high RS content (221 g kg -1 vs. 56 g kg -1 for the untreated flour). Starch was not gelatinized when sorghum flours heated at moisture content of 200 g kg -1 or below. Sorghum protein digestibility and solubility decreased during HMT. The increase in RS of sorghum flour upon HMT was attributed to enhanced amylose-lipid complexes and heat induced structural changes in its protein fraction. HMT can be used to increase RS content in sorghum flour without gelatinizing its starch, thereby providing sorghum flour with unique food applications. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Effect of heat treatment upon the fatigue-crack growth behavior of Alloy 718 weldments

    International Nuclear Information System (INIS)

    Mills, W.J.; James, L.A.

    1981-05-01

    The microstructural features that influenced the room and elevated temperature fatigue-crack growth behavior of as-welded, conventional heat-treated, and modified heat-treated Alloy 718 GTA weldments were studied. Electron fractographic examination of fatigue fracture surfaces revealed that operative fatigue mechanisms were dependent on microstructure, temperatures and stress intensity factor. All specimens exhibited three basic fracture surface appearances at temperatures up to 538 degrees C: crystallographic faceting at low stress intensity range (ΔK) levels, striation, formation at intermediate values, and dimples coupled with striations in the highest (ΔK) regime. At 649 degrees C, the heat-treated welds exhibited extensive intergranular cracking. Laves and δ particles in the conventional heat-treated material nucleated microvoids ahead of the advancing crack front and caused on overall acceleration in crack growth rates at intermediate and high ΔK levels. The modified heat treatment removed many of these particles from the weld zone, thereby improving its fatigue resistance. The dramatically improved fatigue properties exhibited by the as-welded material was attributed to compressive residual stresses introduced by the welding process. 19 refs., 16 figs

  14. New method of processing heat treatment experiments with numerical simulation support

    Science.gov (United States)

    Kik, T.; Moravec, J.; Novakova, I.

    2017-08-01

    In this work, benefits of combining modern software for numerical simulations of welding processes with laboratory research was described. Proposed new method of processing heat treatment experiments leading to obtaining relevant input data for numerical simulations of heat treatment of large parts was presented. It is now possible, by using experiments on small tested samples, to simulate cooling conditions comparable with cooling of bigger parts. Results from this method of testing makes current boundary conditions during real cooling process more accurate, but also can be used for improvement of software databases and optimization of a computational models. The point is to precise the computation of temperature fields for large scale hardening parts based on new method of temperature dependence determination of the heat transfer coefficient into hardening media for the particular material, defined maximal thickness of processed part and cooling conditions. In the paper we will also present an example of the comparison standard and modified (according to newly suggested methodology) heat transfer coefficient data’s and theirs influence on the simulation results. It shows how even the small changes influence mainly on distribution of temperature, metallurgical phases, hardness and stresses distribution. By this experiment it is also possible to obtain not only input data and data enabling optimization of computational model but at the same time also verification data. The greatest advantage of described method is independence of used cooling media type.

  15. In situ heat treatment of a tar sands formation after drive process treatment

    Science.gov (United States)

    Vinegar, Harold J.; Stanecki, John

    2010-09-21

    A method for treating a tar sands formation includes providing a drive fluid to a hydrocarbon containing layer of the tar sands formation to mobilize at least some hydrocarbons in the layer. At least some first hydrocarbons from the layer are produced. Heat is provided to the layer from one or more heaters located in the formation. At least some second hydrocarbons are produced from the layer of the formation. The second hydrocarbons include at least some hydrocarbons that are upgraded compared to the first hydrocarbons produced by using the drive fluid.

  16. Effect of heat treatment oanas irradiation, and combined treatment on the shelf of fresh avocados (Persea americana L)

    International Nuclear Information System (INIS)

    Purwanto, Z.I.; Maha, Munsiah

    1987-01-01

    Effects of heat treatment, gamma irradiation, and combined treatments on the shelf-life of fresh avocados (Persea americana L.). Experiments to determine the effective irradiation conditions to prolong the shelf-life of fresh avocados were conducted at the centre for the Application of Isotopes washed and dried, then divided into 4 groups, namely for control (A), dipped in hot water at 40 0 C for 20 minutes (heat treatment, B), irradiated at a dose of 25 Gy (C), and combination of hot water dipping (40 0 C for 20 minutes) and irradiation at a 25 Gy (D). The samples were stored at room temperature. Evaluation on physical and chemical properties of the samples was done daily up to 10 days' storage. Parameters observed were texture, moisture and fat contents, percentage of weight loss, percentage of mature fruit, and subjective organoleptic evaluation. It was found that treated samples with and without combination treatment were still in good condition until 10 days of storage. It could be concluded that dipping in hot water, either alone or in combination with irradiation at a dose of 25 Gy could extend the shelf-life of fresh avocado up to 10 days at room temperature compared to only 5 days of the control. (author). 2 figs, 8 refs

  17. Effect of heat treatment on the structural and optical properties of tellurite glasses doped erbium

    Energy Technology Data Exchange (ETDEWEB)

    Jlassi, I., E-mail: ifa.jlassi@fst.rnu.tn [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia); Elhouichet, H. [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia); Departement de Physique, Faculte des Sciences de Tunis, Campus ElManar 2092 (Tunisia); Hraiech, S.; Ferid, M. [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia)

    2012-03-15

    The 75TeO{sub 2}-20ZnO-4Na{sub 2}CO{sub 3}-1Er{sub 2}O{sub 3} (in molar ratio) glass system was prepared by the conventional melt-quenching method. As such, the samples prepared were investigated by differential scanning calorimetry (DSC), X-ray diffractrometry (XRD), Raman spectroscopy and infrared luminescence. DSC analyses were carried out on our glass at different heating rates between 5 and 20 Degree-Sign C/min. The result of the annealing temperature on the spectroscopic properties of Er{sup 3+} in tellurite glasses was discussed. The activation energy, for surface crystallization, was determined graphically from a Kissinger-type plot and had a value about 897.2 kJ/mol. Crystalline phases for both {alpha}-TeO{sub 2}, {gamma}-TeO{sub 2} and Zn{sub 2}Te{sub 3}O{sub 8} system were determined by the XRD method and were confirmed by Raman spectroscopy characterizations after heat treatment. The effect of heat treatment on absorption spectra and luminescence properties in the tellurite glass was also investigated. With heat treatment, the ultraviolet absorption edge presented a redshift. As a result, the Judd-Ofelt (J-O) intensity parameters ({Omega}{sub 2}, {Omega}{sub 4}, {Omega}{sub 6}) were determined. The spontaneous emission probabilities of some relevant transitions, the branching ratio and the radiative lifetimes of several excited states of Er{sup 3+} were predicted using intensity J-O parameters. The near infrared emission that corresponds to Er{sup 3+}: {sup 4}I{sub 13/2}{yields}{sup 4}I{sub 15/2} can be significantly enhanced after heat treatment. Notably, it is found that the luminescence lifetime in the present system is much longer than that in most other glasses and glass ceramics. A comparative study on luminescence performance suggests that the obtained glass ceramic is a promising material for Er{sup 3+} doped fiber amplifiers. - Highlights: Black-Right-Pointing-Pointer Tellurite glasses were prepared by conventional melt-quenching method. Black

  18. Effect of heat treatment of wood on the morphology, surface roughness and penetration of simulated and human blood.

    Science.gov (United States)

    Rekola, J; Lassila, L V J; Nganga, S; Ylä-Soininmäki, A; Fleming, G J P; Grenman, R; Aho, A J; Vallittu, P K

    2014-01-01

    Wood has been used as a model material for the development of novel fiber-reinforced composite bone substitute biomaterials. In previous studies heat treatment of wood was perceived to significantly increase the osteoconductivity of implanted wood material. The objective of this study was to examine some of the changing attributes of wood materials that may contribute to improved biological responses gained with heat treatment. Untreated and 140°C and 200°C heat-treated downy birch (Betula pubescens Ehrh.) were used as the wood materials. Surface roughness and the effect of pre-measurement grinding were measured with contact and non-contact profilometry. Liquid interaction was assessed with a dipping test using two manufactured liquids (simulated blood) as well as human blood. SEM was used to visualize possible heat treatment-induced changes in the hierarchical structure of wood. The surface roughness was observed to significantly decrease with heat treatment. Grinding methods had more influence on the surface contour and roughness than heat treatment. The penetration of the human blood in the 200°C heat-treated exceeded that in the untreated and 140°C heat-treated materials. SEM showed no significant change due to heat treatment in the dry-state morphology of the wood. The results of the liquid penetration test support previous findings in literature concerning the effects of heat treatment on the biological response to implanted wood. Heat-treatment has only a marginal effect on the surface contour of wood. The highly specialized liquid conveyance system of wood may serve as a biomimetic model for the further development of tailored fiber-composite materials.

  19. Effect of high intensity pulsed electric fields and heat treatments on vitamins of milk.

    Science.gov (United States)

    Bendicho, Silvia; Espachs, Alexandre; Arántegui, Javier; Martín, Olga

    2002-02-01

    The effects of high intensity pulsed electric field (HIPEF) treatments at room or moderate temperature on water-soluble (thiamine, riboflavin, ascorbic acid) and fat-soluble vitamins (cholecalciferol and tocopherol) were evaluated and compared with conventional thermal treatments. Vitamin retention was determined in two different substrates, milk and simulated skim milk ultrafiltrate (SMUF). Samples were subjected to HIPEF treatments of up to 400 micros at field strengths from 18.3 to 27.1 kV/cm and to heat treatments of up to 60 min at temperatures from 50 to 90 degrees C. No changes in vitamin content were observed after HIPEF or thermal treatments except for ascorbic acid. Milk retained more ascorbic acid after a 400 microstreatment at 22.6 kV/cm (93.4%) than after low (63 degrees C-30 min; 49.7% retained) or high (75 degrees C-15s; 86.7% retained) heat pasteurisation treatments. Retention of ascorbic acid fitted a first-order kinetic model for both HIPEF and thermal processes. First-order constant values varied from 1.8 x 10.4 to 1.27 x 10(-3) micros(-1) for the HIPEF treatments (18.3-27.1 kV/cm) and, for thermal processing ranged from 5 x 10(-3) to 8 x 10(-2) min(-1) (50-90 degrees C). No significant differences were found between the results obtained after applying HIPEF treatments at room or moderate temperature. However, results depended on the treatment media. A beneficial effect of natural skim milk components, mainly proteins, was observed on the preservation of ascorbic acid, since skim milk retained more ascorbic acid than SMUF after HIPEF treatments.

  20. Dimensional Changes of Nb$_{3}$Sn Rutherford Cables During Heat Treatment

    CERN Document Server

    Rochepault, E; Ambrosio, G; Anerella, M; Ballarino, A; Bonasia, A; Bordini, B; Cheng, D; Dietderich, D R; Felice, H; Garcia Fajardo, L; Ghosh, A; Holik, E F; Izquierdo Bermudez, S; Perez, J C; Pong, I; Schmalzle, J; Yu, M

    2016-01-01

    In high field magnet applications, Nb$_{3}$Sn coils undergo a heat treatment step after winding. During this stage, coils radially expand and longitudinally contract due to the Nb$_{3}$Sn phase change. In order to prevent residual strain from altering superconducting performances, the tooling must provide the adequate space for these dimensional changes. The aim of this paper is to understand the behavior of cable dimensions during heat treatment and to provide estimates of the space to be accommodated in the tooling for coil expansion and contraction. This paper summarizes measurements of dimensional changes on strands, single Rutherford cables, cable stacks, and coils performed between 2013 and 2015. These samples and coils have been performed within a collaboration between CERN and the U.S. LHC Accelerator Research Program to develop Nb$_{3}$Sn quadrupole magnets for the HiLumi LHC. The results are also compared with other high field magnet projects.

  1. EVALUATION OF PRECIPITATION HARDENING HEAT TREATMENT OF PH 17-7 STAINLESS STEEL SPRING

    Directory of Open Access Journals (Sweden)

    A. A. Babakoohi Ashrafi

    2016-06-01

    Full Text Available In this paper, the influence of heat treatment on PH17-7 stainless steel spring was evaluated. Precipitation hardening phenomenon of  PH 17-7 steel was evaluated in three stages. First, the spring constant changes with time and temperature was evaluated. Second, the spring constant changes with respect to its original length at constant temperature and time with blocking (spring length after compression, 18 and 21 mm were investigated.  And finally, the spring heat treatment at 480 °C for 80 min and then holding at 230 °C in oil bath for 60 min without blocking were investigated. The results showed that the use of 18 mm block have large spring constant than 21 mm block. The optimal conditions (480°C for 80 min for this spring to reaching maximum spring constant were determined.

  2. Heat Treatment Optimization Studies on PIT Nb$_3$Sn Strand for the NED Project

    CERN Document Server

    Boutboul, T; den Ouden, A; Pedrini, D; Seeber, B; Volpini, G

    2009-01-01

    For the Next European Dipole (NED) program, a Powder-In-Tube (PIT) strand was successfully developed by SMI. This high-performance Nb$_{3}$Sn strand presents a non-copper critical current density of ~ 2500 A/mm2 at 12 T applied field and 4.2 K and a filament diameter around 50 µm. Extensive heat treatment optimization studies were performed in order to maximize both critical current and RRR, with a plateau temperature down to 625 oC and duration up to 400 hours. It appears that a critical current enhancement of ~ 10 % can be achieved for a reaction schedule of 320 hours at 625 oC with non-copper critical current density respectively exceeding 2700 and 1500 A/mm2 at 12 and 15 T (4.2 K). Thanks to this modified heat treatment, this strand completely fulfils the NED stringent specification.

  3. Effect of fat type and heat treatment on the microstructure of meat emulsions

    DEFF Research Database (Denmark)

    Miklos, Rikke; Lametsch, René; Nielsen, Mikkel Schou

    2013-01-01

    -polymers and stabilize the protein network. Differences in the physicochemical properties of saturated and unsaturated lipids affect the distribution of fat and thereby the functionality and quality of the final product. The objectives were to study the effects of lipid type and heat treatment on changes...... imaging of the tomograms were used to analyse the impact of lipid type on spatial fat distribution, microstructure of the protein network and structural changes caused by heat treatment. The tomograms showed that the fat distribution in the meat emulsions depended on the physicochemical properties......In comminuted meat products the gel-forming abilities of the myofibrillar proteins are of major importance. In meat emulsions fat will be present in globules which are stabilized by a membrane coating made of salt-soluble proteins. These discontinuous fat particles act as fillers or co...

  4. To investigate the effect of heat treatment on fracture toughness of welded joints

    International Nuclear Information System (INIS)

    Hameed, A.; Pasha, R.A.; Shah, M.

    2013-01-01

    Annealing as a post weld heat treatment (PWHT), increases toughness in the welding joints of medium carbon steel in the same way as it increases toughness of the non-welded medium carbon steel. Measurement of increase in toughness through PWHT is focus of the present research work. Welded samples of commercially available steel AISI -1035 have been used for the proposed evaluation. The samples welded by two different techniques namely oxyacetylene gas welding and manual metal arc welding, passed through annealing process along with non-welded samples for comparison of increase in toughness. Toughness measured by impact tests revealed the improvement, which in the order of increasing effects is in gas welded, electric welded and non-welded samples. The aim of the present research was to measure the improvement in fracture toughness through post weld heat treatment (annealing). It has been shown that toughness increases as the structural flaws decrease. (author)

  5. Enhancement of methane gas sensing characteristics of graphene oxide sensor by heat treatment and laser irradiation.

    Science.gov (United States)

    Assar, Mohammadreza; Karimzadeh, Rouhollah

    2016-12-01

    The present study uses a rapid, easy and practical method for cost-effective fabrication of a methane gas sensor. The sensor was made by drop-casting a graphene oxide suspension onto an interdigital circuit surface. The electrical conductivity and gas-sensing characteristics of the sensor were determined and then heat treatment and in situ laser irradiation were applied to improve the device conductivity and gas sensitivity. Real-time monitoring of the evolution of the device current as a function of heat treatment time revealed significant changes in the conductance of the graphene oxide sensor. The use of low power laser irradiation enhanced both the electrical conductivity and sensing response of the graphene oxide sensor. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Effect of phosphorus and heat treatment on microstructure of Al-25%Si alloy

    Directory of Open Access Journals (Sweden)

    Bo Dang

    2017-01-01

    Full Text Available It is known that phosphorus can refine the primary silicon and heat treatment can spheroidize the eutectic silicon. This paper presents an optimal combination of heat treatment processes and P refinement on hypereutectic Al-Si alloy. The optimal P addition amount, and the solution and aging temperatures for Al-25%Si alloy were obtained through the orthogonal experiment, and their modification effects were discussed. The results show that P addition has the greatest modification effect, followed by aging temperature, and the modification effect of solution temperature is the least. The optimized modification parameters are: addition of 0.6% P, solution at 540 篊 and aging at 160 篊 . In addition, the cooling curve, superheating and hardness of the alloy were also analyzed.

  7. Influence of heat treatment on the wear life of hydraulic fracturing tools

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Chao; Liu, Yonghong; Wang, Hanxiang; Qin, Jie; Shen, Yang; Zhang, Shihong [China University of Petroleum, Qingdao (China)

    2017-02-15

    Wear phenomenon has caused severe damage or failure of fracturing tools in oil and gas industry. In this paper, influence of heat treatment on the mechanical properties and wear resistance of fracturing tool made of lamellar graphite grey cast iron were investigated. The surface composition and microstructure were characterized by X-ray diffraction (XRD) and metallographic microscope. Sliding wear tests were performed to study the tribological behavior. Tests results showed that wear rates of treated specimens decreased by 33 %. Besides, worn morphology and wear debris were analyzed using Scanning electron microscope (SEM) and Energy dispersive Xray spectra (EDS). Wear failure mechanisms of specimens were identified. Furthermore, on-site experiment results indicated that wear loss of treated samples decreased by 37.5 %. The wear life of hydraulic fracturing tools can be improved obviously by the heat treatment.

  8. Effects of Heat Treatment on SiC-SiC Ceramic Matrix Composites

    Science.gov (United States)

    Knauf, Michael W.

    Residual stresses resulting from the manufacturing process found within a silicon carbide/silicon carbide (SiC/SiC) ceramic matrix composite were thoroughly investigated through the use of high-energy X-ray diffraction and Raman microspectroscopy. The material system studied was a Rolls-Royce composite produced with Hi-Nicalon fibers woven into a five harness satin weave, coated with boron nitride and silicon carbide interphases, and subsequently infiltrated with silicon carbide particles and a silicon matrix. Constituent stress states were measured before, during, and after heat treatments ranging from 900 °C to 1300 °C for varying times between one and sixty minutes. Stress determination methods developed through these analyses can be utilized in the development of ceramic matrix composites and other materials employing boron-doped silicon. X-ray diffraction experiments were performed at the Argonne National Laboratory Advanced Photon Source to investigate the evolution of constituent stresses through heat treatment, and determine how stress states are affected at high temperature through in situ measurements during heat treatments up to 1250 °C for 30 minutes. Silicon carbide particles in the as-received condition exhibited a nearly isotropic stress state with average tensile stresses of approximately 300 MPa. The silicon matrix exhibited a complimentary average compressive stress of approximately 300 MPa. Strong X-ray diffraction evidence is presented demonstrating solid state boron diffusion and increased boron solubility found in silicon throughout heat treatment. While the constituent stress states did evolve through the heat treatment cycles, including approaching nearly stress-free conditions at temperatures close to the manufacturing temperature, no permanent relaxation of stress was observed. Raman spectroscopy was utilized to investigate stresses found within silicon carbide particles embedded within the matrix and the silicon matrix as an alternate

  9. Influence of heat treatment on the wear life of hydraulic fracturing tools

    International Nuclear Information System (INIS)

    Zheng, Chao; Liu, Yonghong; Wang, Hanxiang; Qin, Jie; Shen, Yang; Zhang, Shihong

    2017-01-01

    Wear phenomenon has caused severe damage or failure of fracturing tools in oil and gas industry. In this paper, influence of heat treatment on the mechanical properties and wear resistance of fracturing tool made of lamellar graphite grey cast iron were investigated. The surface composition and microstructure were characterized by X-ray diffraction (XRD) and metallographic microscope. Sliding wear tests were performed to study the tribological behavior. Tests results showed that wear rates of treated specimens decreased by 33 %. Besides, worn morphology and wear debris were analyzed using Scanning electron microscope (SEM) and Energy dispersive Xray spectra (EDS). Wear failure mechanisms of specimens were identified. Furthermore, on-site experiment results indicated that wear loss of treated samples decreased by 37.5 %. The wear life of hydraulic fracturing tools can be improved obviously by the heat treatment

  10. Effects of heat treatment on mechanical properties of h13 steel

    Science.gov (United States)

    Guanghua, Yan; Xinmin, Huang; Yanqing, Wang; Xingguo, Qin; Ming, Yang; Zuoming, Chu; Kang, Jin

    2010-12-01

    Heat treatment on the mechanical properties of H13 hot working die steel for die casting is discussed. The H13 steel for die casting was treated by different temperatures of vacuum quenching, tempering, and secondary tempering to investigate its mechanical properties. Strength, plasticity, hardness, and impact toughness of the H13 hot working die steel for die casting were measured. Microstructure, grain size, and carbide particle size after heat treatment have a great impact on the mechanical properties of H13 hot working die steel for die casting. The microstructure of the H13 was analyzed by scanning electron microscopy (SEM) and by a metallographic microscope. It is found that H13 exhibits excellent mechanical properties after vacuum quenching at 1050°C and twice tempering at 600°C.

  11. Residual stress and mechanical properties of SiC ceramic by heat treatment

    International Nuclear Information System (INIS)

    Yoon, H.K.; Kim, D.H.; Shin, B.C.

    2007-01-01

    Full text of publication follows: Silicon carbide is a compound of relatively low density, high hardness, elevated thermal stability and good thermal conductivity, resulting in good thermal shock resistance. Because of these properties, SiC materials are widely used as abrasives and refractories. In this study, SiC single and poly crystals was grown by the sublimation method using the SiC seed crystal and SiC powder as the source material. Mechanical properties of SiC single and poly crystals are carried out by using the nano-indentation method and small punch test after the heat treatment. As a result, mechanical properties of SiC poly crystal had over double than single. And SiC single and poly crystals were occurred residual stress, but residual stress was shown relaxant properties by the effect of heat treatment. (authors)

  12. Decreased survival of prostate cancer cells in vitro by combined treatment of heat and an antioxidant inhibitor diethyldithiocarbamate (DDC).

    Science.gov (United States)

    Moriyama-Gonda, Nobuko; Igawa, Mikio; Shiina, Hiroaki; Urakami, Shinji; Terashima, Masaharu

    2003-11-01

    The aim of this study was to examine a modulation of thermotolerance by treatment with combination of heat and the antioxidant inhibitor diethyldithiocarbamate (DDC) of the PC-3 prostate cancer cells. To determine thermotolerance, cells were heated once or twice. Two 1 h exposures at 43 degrees C, with a recovery period in between, revealed better survival/recovery of cells after the second exposure than after the first (fig. 1A + 1B). Additional experiments were performed, heating cells twice (fig. 1B + 1C). First, cells were heated at 43 degrees C for 1 h and, after various recovery times (intervals) at 37 degree C, subsequently reheated at 44 degrees C for 1 h. To ensure effective cell killing, efficiency of the combined treatments of 1 mM DDC and heating at 43 or 44 degrees C for 1 h was estimated by measuring cell survival, reactive oxygen species (ROS) generation, superoxide dismutase (SOD) activity and heat shock protein 70 (hsp 70) expression. To obtain a more effective method for subsequent heat exposure, cells were heated twice after a 24 h interval in the presence or absence of 1 mM DDC. ROS generation and SOD activity immediately increased correlating with duration of heating, but their levels gently decreased with time after discontinuation of heating. On the other hand, hsp 70 levels slowly increased, also correlating with duration of heating but continued to increase with time after discontinuation of heating for a certain period. DDC administration coupled with heating at 43 or 44 degrees C significantly decreased cell survival compared to heating alone (p DDC as compared to heat alone at 43 and 44 degrees C (p DDC could have potential benefits in the treatment of prostate cancer.

  13. Anisotropic lattice softening near the structural phase transition in the thermosalient crystal 1,2,4,5-tetrabromobenzene.

    Science.gov (United States)

    Zakharov, Boris A; Michalchuk, Adam A L; Morrison, Carole A; Boldyreva, Elena V

    2018-03-28

    The thermosalient effect (crystal jumping on heating) attracts much attention as both an intriguing academic phenomenon and in relation to its potential for the development of molecular actuators but its mechanism remains unclear. 1,2,4,5-Tetrabromobenzene (TBB) is one of the most extensively studied thermosalient compounds that has been shown previously to undergo a phase transition on heating, accompanied by crystal jumping and cracking. The difference in the crystal structures and intermolecular interaction energies of the low- and high-temperature phases is, however, too small to account for the large stress that arises over the course of the transformation. The energy is released spontaneously, and crystals jump across distances that exceed the crystal size by orders of magnitude. In the present work, the anisotropy of lattice strain is followed across the phase transition by single-crystal X-ray diffraction, focusing on the structural evolution from 273 to 343 K. A pronounced lattice softening is observed close to the transition point, with the structure becoming more rigid immediately after the phase transition. The diffraction studies are further supported by theoretical analysis of pairwise intermolecular energies and zone-centre lattice vibrations. Only three modes are found to monotonically soften up to the phase transition, with complex behaviour exhibited by the remaining lattice modes. The thermosalient effect is delayed with respect to the structural transformation itself. This can originate from the martensitic mechanism of the transformation, and the accumulation of stress associated with vibrational switching across the phase transition. The finding of this study sheds more light on the nature of the thermosalient effect in 1,2,4,5-tetrabromobenzene and can be applicable also to other thermosalient compounds.

  14. Endotoxin inactivation via steam-heat treatment in dilute simethicone emulsions used in biopharmaceutical processes.

    Science.gov (United States)

    Britt, Keith A; Galvin, Jeffrey; Gammell, Patrick; Nti-Gyabaah, Joseph; Boras, George; Kolwyck, David; Ramirez, José G; Presente, Esther; Naugle, Gregory

    2014-01-01

    Simethicone emulsion is used to regulate foaming in cell culture operations in biopharmaceutical processes. It is also a potential source of endotoxin contamination. The inactivation of endotoxins in dilute simethicone emulsions was assessed as a function of time at different steam temperatures using a Limulus amebocyte lysate kinetic chromogenic technique. Endotoxin inactivation from steam-heat treatment was fit to a four-parameter double exponential decay model, which indicated that endotoxin inactivation was biphasic, consisting of fast and slow regimes. In the fast regime, temperature-related effects were dominant. Transitioning into the slow regime, the observed temperature dependence diminished, and concentration-related effects became increasingly significant. The change in the Gibbs free energy moving through the transition state indicated that a large energy barrier must be overcome for endotoxin inactivation to occur. The corresponding Arrhenius pre-exponential factor was >10(12) s(-1) suggesting that endotoxins in aqueous solution exist as aggregates. The disorder associated with the endotoxin inactivation reaction pathway was assessed via the change in entropy moving through the transition state. This quantity was positive indicating that endotoxin inactivation may result from hydrolysis of individual endotoxin molecules, which perturbs the conformation of endotoxin aggregates, thereby modulating the biological activity observed. Steam-heat treatment decreased endotoxin levels by 1-2 logarithm (log) reduction (LRV), which may be practically relevant depending on incoming raw material endotoxin levels. Antifoam efficiency and cell culture performance were negligibly impacted following steam-heat treatment. The results from this study show that steam-heat treatment is a viable endotoxin control strategy that can be implemented to support large-scale biopharmaceutical manufacturing. © 2014 American Institute of Chemical Engineers.

  15. Heat treatment of thin NiTi filaments by electric current

    Czech Academy of Sciences Publication Activity Database

    Pilch, Jan; Heller, Luděk; Šittner, Petr

    2010-01-01

    Roč. 2, č. 1 (2010), 1-4 ISSN N R&D Projects: GA ČR GAP108/10/1296; GA AV ČR(CZ) IAA200100627 Grant - others:EC "UPWIND" -Integrated Wind Turbine Design(XE) 019945 (SES6) Institutional research plan: CEZ:AV0Z10100520 Keywords : NiTi * SMA * heat treatment * martensitic transformation Subject RIV: BM - Solid Matter Physics ; Magnetism

  16. Laboratory Investigation on Physical and Mechanical Properties of Granite After Heating and Water-Cooling Treatment

    Science.gov (United States)

    Zhang, Fan; Zhao, Jianjian; Hu, Dawei; Skoczylas, Frederic; Shao, Jianfu

    2018-03-01

    High-temperature treatment may cause changes in physical and mechanical properties of rocks. Temperature changing rate (heating, cooling and both of them) plays an important role in those changes. Thermal conductivity tests, ultrasonic pulse velocity tests, gas permeability tests and triaxial compression tests are performed on granite samples after a heating and rapid cooling treatment in order to characterize the changes in physical and mechanical properties. Seven levels of temperature (from 25 to 900 °C) are used. It is found that the physical and mechanical properties of granite are significantly deteriorated by the thermal treatment. The porosity shows a significant increase from 1.19% at the initial state to 6.13% for samples heated to 900 °C. The increase in porosity is mainly due to three factors: (1) a large number of microcracks caused by the rapid cooling rate; (2) the mineral transformation of granite through high-temperature heating and water-cooling process; (3) the rapid cooling process causes the mineral particles to weaken. As the temperature of treatment increases, the thermal conductivity and P-wave velocity decrease while the gas permeability increases. Below 200 °C, the elastic modulus and cohesion increase with temperature increasing. Between 200 and 500 °C, the elastic modulus and cohesion have no obvious change with temperature. Beyond 500 °C, as the temperature increases, the elastic modulus and cohesion obviously decrease and the decreasing rate becomes slower with the increase in confining pressure. Poisson's ratio and internal frictional coefficient have no obvious change as the temperature increases. Moreover, there is a transition from a brittle to ductile behavior when the temperature becomes high. At 900 °C, the granite shows an obvious elastic-plastic behavior.

  17. Mild heat treatments induce long-term changes in metabolites associated with energy metabolism in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Sarup, Pernille; Petersen, Simon Metz Mariendal; Nielsen, Niels Christian

    2016-01-01

    treatments on the metabolome of male Drosophila melanogaster. 10 days after the heat treatment, metabolic aging appears to be slowed down, and a treatment response with 40 % higher levels of alanine and lactate and lower levels of aspartate and glutamate were measured. All treatment effects had disappeared...

  18. Study on the application of thickened welds without post weld heat treatment for containment vessels

    International Nuclear Information System (INIS)

    Takeuchi, T.; Fukaya, T.; Sato, M.; Takano, G.

    1978-01-01

    As material for containment vessels, SGV49 steel plates are mainly used. However, those used for this purpose are limited in thickness to smaller than 38 mm. This is because the present standard requires welds thicker than 38 mm to be subjected to post weld heat treatment but operation on the site is practically difficult. In the case of 3-loop containment vessels of pressurized water type reactors, use of 38 mm SGV49 brings an increase in their height and this is disadvantageous from a seismic viewpoint. Therefore, use of 45 mm-thick steel material has become necessary in order to increase design internal pressure and reduce the height of the vessels. To investigate the propriety of the use of 45 mm-thick SGV49 for this purpose without post weld heat treatment we investigated the basic performances of base metal and welded joints. We also conducted large-scale embrittlement fracture tests (CT test, deep notch test, wide plate tensile test and ESSO test) in order to examine whether welds not subjected to post weld heat treatment are safe against embrittlement fracture under the operating conditions of the vessels. The results proved that the welds of SGV49 steel plates are safe enough under the operating conditions. (author)

  19. Calculation of α/γ equilibria in SA508 grade 3 steels for intercritical heat treatment

    International Nuclear Information System (INIS)

    Lee, B.J.; Kim, H.D.; Hong, J.H.

    1998-01-01

    An attempt has been made to suggest an optimum temperature for intercritical heat treatment of an SA508 grade 3 steel for nuclear pressure vessels, based on thermodynamic calculation of the α/γ phase equilibria. A thermodynamic database constructed for the Fe-Mn-Ni-Mo-Cr-Si-V-Al-C-N ten-component system and an empirical criterion that the amount of reformed austenite should be around 40 pct were used for thermodynamic calculation and derivation of the optimum heat-treatment temperature, respectively. The calculated optimum temperature, 720 C, was in good agreement with an experimentally determined temperature of 725 C obtained through an independent experimental investigation of the same steel. The agreement between the calculated and measured fraction of reformed austenite during the intercritical heat treatment was also confirmed. Based on the agreement between calculation and experiment, it could be concluded that thermodynamic calculations can be successfully applied to the materials and/or process design as an additive tool to the already established technology, and that the currently constructed thermodynamic database for steel systems shows an accuracy that makes such applications possible

  20. Heat treatment eliminates 'Candidatus Liberibacter asiaticus' from infected citrus trees under controlled conditions.

    Science.gov (United States)

    Hoffman, Michele T; Doud, Melissa S; Williams, Lisa; Zhang, Mu-Qing; Ding, Fang; Stover, Ed; Hall, David; Zhang, Shouan; Jones, Lisa; Gooch, Mark; Fleites, Laura; Dixon, Wayne; Gabriel, Dean; Duan, Yong-Ping

    2013-01-01

    Huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide. The three known causal agents of HLB are species of α-proteobacteria: 'Candidatus Liberibacter asiaticus', 'Ca. L. africanus', and 'Ca. L. americanus'. Previous studies have found distinct variations in temperature sensitivity and tolerance among these species. Here, we describe the use of controlled heat treatments to cure HLB caused by 'Ca. L. asiaticus', the most prevalent and heat-tolerant species. Using temperature-controlled growth chambers, we evaluated the time duration and temperature required to suppress or eliminate the 'Ca. L. asiaticus' bacterium in citrus, using various temperature treatments for time periods ranging from 2 days to 4 months. Results of quantitative polymerase chain reaction (qPCR) after treatment illustrate significant decreases in the 'Ca. L. asiaticus' bacterial titer, combined with healthy vigorous growth by all surviving trees. Repeated qPCR testing confirmed that previously infected, heat-treated plants showed no detectable levels of 'Ca. L. asiaticus', while untreated control plants remained highly infected. Continuous thermal exposure to 40 to 42°C for a minimum of 48 h was sufficient to significantly reduce titer or eliminate 'Ca. L. asiaticus' bacteria entirely in HLB-affected citrus seedlings. This method may be useful for the control of 'Ca. Liberibacter'-infected plants in nursery and greenhouse settings.

  1. Improvement of the current efficiency of an Al-Zn-In anode by heat-treatment

    International Nuclear Information System (INIS)

    Lin, J.C.; Shih, H.C.

    1987-01-01

    Aluminum anodes, each having one of several heat-treatments [namely as-cast (A), furnace-cooled (B), quenched (C), and quenched and aged (D-1)] were electrically coupled to structural steels to provide cathodic protection. The electro-chemical potential of each galvanic couple depended on the type of heat-treatment: anodes A, B, and C exhibited a potential of -1.10V, and anode D-1 was somewhat less negative at -0.95V. Empirical relationships between galvanic current density and area ratio (AR), based on 120h tests, have been established. Surface examination showed that anodes A, B, and C corrode uniformly, whereas anode D-1 dissolves locally. Results showed that the current efficiency of a sacrificial aluminum anode is dependent on its microstructure, which is, in turn, affected by its heat-treatment. Both anodes A and B possessed an equilibrium precipitate of In and the corresponding efficiencies did not vary with time. However, anode C, and especially anode D-1, suffered from aging, and their efficiencies varied with time. The microstructure of anode C contained thermal defects such as dislocation loops, while anode D-1 contained both dislocation loops and microsegregates. Results confirm that as-cast and furnace-cooled anodes have the best efficiencies (94-98%), while quenched and aged anodes have significantly lower efficiencies

  2. Preliminary heat treatment of 4KhM2Fch die steel

    International Nuclear Information System (INIS)

    Leonidov, V.M.; Berezkin, Y.A.; Nikitenko, E.V.

    1986-01-01

    To improve the machinability and preparation of the structure for hardening, die steels are given a preliminary treatment which provides a reduction in hardness as a result of separation in the structure of the carbide and ferrite phases, coagulation of the carbides, and acquisition by them of a granular form and also the obtaining of fine grains and a uniform distribution of the structural constituents. The microstructure was evaluated after etching in 4% nital on an MIM-8M microscope. The 4KhM2Fch steel was given a preliminary heat treatment of normalize and anneal. It was concluded that for 4KhM2Fch steel a preliminary heat treatment of normalizing from 950 0 C with a hold of 1.5-2 h, annealing at 750-760 0 C with a hold of 2-3 h, cooling to the isothermal temperature of 670-680 0 C with a hold of 3-4 h, and further air cooling is recommended. The structure after such a heat is granular pearlite with a rating 1-2 and a hardness of 220-250 HB

  3. Effects of isothermal heat treatment on nanostructured bainite morphology and microstructures in laser cladded coatings

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yanbing [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Feng, Kai; Lu, Fenggui; Zhang, Ke [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composite, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Zhuguo, E-mail: lizg@sjtu.edu.cn [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Hosseini, Seyed Reza Elmi [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Min [Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composite, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2015-12-01

    Highlights: • Nanobainitic coatings under 200, 250 and 300 °C heat treatments are fabricated. • The size of bainite sheaves increased with the isothermal temperature increasing. • Textured and chaotic distributions are observed in 200 and 300 °C microstructures. • The evolution model of nanobainite morphology is established and analyzed. • The bainitic ferrite of 200 °C heat treatment has a true thickness of 45 nm. - Abstract: Laser cladding and subsequent isothermal heat treatments have been used to fabricate nanostructured bainitic coatings. XRD has been used to determine the kinetics of bainitic transformation process. OM, SEM and TEM have been used to characterize the morphology and microstructures at different stages of transformation. The results showed that at the initial stage of bainitic transformation, the bainite sheaves are short and thin at a relatively low transformation temperature. The fully transformed bainitic microstructure obtained at a relatively high temperature present a textured morphology. The chaotic growth orientations of the sheaves and the island like of the retained austenite have been observed at the low transformation temperature. A simple model has been established to describe the microstructures and the bainite sheaves growth evolutions during the isothermal holding at the different transformed temperatures. The morphology and distribution of the bainite in the coatings were analyzed by using the nucleation and growth rate of bainitic transformation theories, which is consisted with the experiment results.

  4. Effects of isothermal heat treatment on nanostructured bainite morphology and microstructures in laser cladded coatings

    International Nuclear Information System (INIS)

    Guo, Yanbing; Feng, Kai; Lu, Fenggui; Zhang, Ke; Li, Zhuguo; Hosseini, Seyed Reza Elmi; Wang, Min

    2015-01-01

    Highlights: • Nanobainitic coatings under 200, 250 and 300 °C heat treatments are fabricated. • The size of bainite sheaves increased with the isothermal temperature increasing. • Textured and chaotic distributions are observed in 200 and 300 °C microstructures. • The evolution model of nanobainite morphology is established and analyzed. • The bainitic ferrite of 200 °C heat treatment has a true thickness of 45 nm. - Abstract: Laser cladding and subsequent isothermal heat treatments have been used to fabricate nanostructured bainitic coatings. XRD has been used to determine the kinetics of bainitic transformation process. OM, SEM and TEM have been used to characterize the morphology and microstructures at different stages of transformation. The results showed that at the initial stage of bainitic transformation, the bainite sheaves are short and thin at a relatively low transformation temperature. The fully transformed bainitic microstructure obtained at a relatively high temperature present a textured morphology. The chaotic growth orientations of the sheaves and the island like of the retained austenite have been observed at the low transformation temperature. A simple model has been established to describe the microstructures and the bainite sheaves growth evolutions during the isothermal holding at the different transformed temperatures. The morphology and distribution of the bainite in the coatings were analyzed by using the nucleation and growth rate of bainitic transformation theories, which is consisted with the experiment results.

  5. ANALYSIS OF PITTING CORROSION ON AN INCONEL 718 ALLOY SUBMITTED TO AGING HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    Felipe Rocha Caliari

    2014-10-01

    Full Text Available Inconel 718 is one of the most important superalloys, and it is mainly used in the aerospace field on account of its high mechanical strength, good resistance to fatigue and creep, good corrosion resistance and ability to operate continuously at elevated temperatures. In this work the resistance to pitting corrosion of a superalloy, Inconel 718, is analyzed before and after double aging heat treatment. The used heat treatment increases the creep resistance of the alloy, which usually is used up to 0.6 Tm. Samples were subjected to pitting corrosion tests in chloride-containing aqueous solution, according to ASTM-F746-04 and the procedure described by Yashiro et al. The results of these trials show that after heat treatment the superalloy presents higher corrosion resistance, i.e., the pitting corrosion currents of the as received surfaces are about 6 (six times bigger (~0.15 mA than those of double aged surfaces (~0.025 mA.

  6. Effects of heat treatment conditions on microstructure and mechanical properties of AISI 420 steel

    Energy Technology Data Exchange (ETDEWEB)

    Scheuer, C.J.; Fraga, R.A.; Cardoso, R.P.; Brunatto, S.F. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Departamento de Engenharia Mecanica. Grupo de Tecnologia de Fabricacao Assistida por Plasma e Metalurgia do Po

    2014-07-01

    The cycle control of heat treatments, on the quenching and tempering operation of AISI 420 stainless steel, is essential for improved material performance. The adequate choice of heat treatment parameters, can lead an optimization on its mechanical properties and corrosion resistance. Thus, this paper aims to investigate the effects of quenchants medium, and austenitizing and tempering temperatures, on the microstructure and mechanical properties of AISI 420 steel. Different heat treatments cycles were studied: 1) samples were austenitized at 1050°C and water, oil and air quenched; 2) samples were austenitized at range temperatures of 950-1050°C and oil quenched; and 3) as-quenched samples were tempering at range temperatures of 400-500°C. Treated samples were characterized by optical microscopy, X-ray diffractometry and hardness measurements. The samples hardness increases with increasing cooling rate (water > oil > air quenched). Water quenched samples presented crack after cooling to room temperature. Samples hardness also increases with austenitizing temperature increasing, and decreases with increasing tempering temperature. (author)

  7. Sensitivity of Austempering Heat Treatment of Ductile Irons to Changes in Process Parameters

    Science.gov (United States)

    Boccardo, A. D.; Dardati, P. M.; Godoy, L. A.; Celentano, D. J.

    2018-03-01

    Austempered ductile iron (ADI) is frequently obtained by means of a three-step austempering heat treatment. The parameters of this process play a crucial role on the microstructure of the final product. This paper considers the influence of some process parameters (i.e., the initial microstructure of ductile iron and the thermal cycle) on key features of the heat treatment (such as minimum required time for austenitization and austempering and microstructure of the final product). A computational simulation of the austempering heat treatment is reported in this work, which accounts for a coupled thermo-metallurgical behavior in terms of the evolution of temperature at the scale of the part being investigated (the macroscale) and the evolution of phases at the scale of microconstituents (the microscale). The paper focuses on the sensitivity of the process by looking at a sensitivity index and scatter plots. The sensitivity indices are determined by using a technique based on the variance of the output. The results of this study indicate that both the initial microstructure and the thermal cycle parameters play a key role in the production of ADI. This work also provides a guideline to help selecting values of the appropriate process parameters to obtain parts with a required microstructural characteristic.

  8. Sensitivity of Austempering Heat Treatment of Ductile Irons to Changes in Process Parameters

    Science.gov (United States)

    Boccardo, A. D.; Dardati, P. M.; Godoy, L. A.; Celentano, D. J.

    2018-06-01

    Austempered ductile iron (ADI) is frequently obtained by means of a three-step austempering heat treatment. The parameters of this process play a crucial role on the microstructure of the final product. This paper considers the influence of some process parameters ( i.e., the initial microstructure of ductile iron and the thermal cycle) on key features of the heat treatment (such as minimum required time for austenitization and austempering and microstructure of the final product). A computational simulation of the austempering heat treatment is reported in this work, which accounts for a coupled thermo-metallurgical behavior in terms of the evolution of temperature at the scale of the part being investigated (the macroscale) and the evolution of phases at the scale of microconstituents (the microscale). The paper focuses on the sensitivity of the process by looking at a sensitivity index and scatter plots. The sensitivity indices are determined by using a technique based on the variance of the output. The results of this study indicate that both the initial microstructure and the thermal cycle parameters play a key role in the production of ADI. This work also provides a guideline to help selecting values of the appropriate process parameters to obtain parts with a required microstructural characteristic.

  9. Alkali-heat treatment of a low modulus biomedical Ti-27Nb alloy

    International Nuclear Information System (INIS)

    Zhou, Y; Wang, Y B; Zhang, E W; Cheng, Y; Xiong, X L; Zheng, Y F; Wei, S C

    2009-01-01

    This study focuses on the surface modification of a near β-type Ti-27 wt.% Nb alloy by alkali-heat treatment. The influence of alkali concentration, alkali-treated time and alkali-treated temperature on the microstructure and constitutional phases of the modified surface is investigated by SEM, XRD and ICP. Immersion experiments in a simulated body fluid (SBF) were carried out to examine the Ca-P phase forming ability of the modified surfaces. The SEM observation and XRD analysis revealed that a sodium titanate layer is formed after alkali-heat treatment. The morphology and Ca-P phase forming of the layer are greatly affected by the surface roughness of the samples, the alkali concentration, the alkali-treated time and alkali-treated temperature. The results of SBF immersion, which are obtained by ICP analysis, indicate that the activated sodium titanate layer prepared by alkali-heat treatment is beneficial to further improving the biocompatibility of the Ti-27 wt.% Nb alloy.

  10. Inactivation of T4-phages by heat and γ-irradiation treatment in respect to sludge hygienization

    International Nuclear Information System (INIS)

    Farniok, C.; Turanitz, K.; Stehlik, G.; Meyrath, J.

    1977-04-01

    The effects of γ-irradiation, heat treatment and combined heat/irradiation treatments on T 4 -bacteriophages were studied and evaluated in surviving fractions. To ascertain the extent of inactivation, the formation of plaque was studied in the host organism Escherichia coli K 12 D 10. A 90-minute heat treatment of the bacteriolysat at 55 0 C did not inactivate the bacteriophages, whereas the number of plaque-forming bacteriophages was decreased by 50% at 60 0 C. At 65 0 C a linear correlation of heating period and the logarithm of relative number of phages was observed. After 30 minutes exposure to 70 0 C only few bacteriophages were traced in the plaque test. By inactivation of T 4 -phages after exposure to γ-irradiation a linear correlation of irradiation dose and the logarithm of the relative number of surviving bacteriophages was found. The combined method of heat and irradiation treatments resulted in a synergistic effect. (author)

  11. Role of the preliminary heat treatment in anisothermic eutectoid change of the cast iron

    Directory of Open Access Journals (Sweden)

    T. Szykowny

    2011-07-01

    Full Text Available Preliminary heat treatment, preceding continuous cooling of the iron casting, assumed in the research, complies with the applied in prac- tice single normalization, double normalization or normalization with slow cooling. In each of these cases continuous cast iron cooling has been begun from the same temperature 925°C. CCT diagrams have been made with use of metallographic method. The mechanism, kinet- ics and the final structure of eutectoid change of the cast iron after such treatment have been traced.

  12. The effect of veneering and heat treatment on the flexural strength of Empress 2 ceramics.

    Science.gov (United States)

    Cattell, M J; Palumbo, R P; Knowles, J C; Clarke, R L; Samarawickrama, D Y D

    2002-05-01

    The aims of the study were to test and compare the biaxial flexural strength and reliability of Empress 2 ceramics after heat treatment and the addition of the veneering material and to characterise their microstructures. Forty disc specimens (2 x 14 mm) and forty disc specimens (1 x 14 mm) were produced by heat pressing in the EP 500 press furnace. Group 1 (2 x 14 mm Empress 2 core) was as heat pressed and group 2 (2 x 14 mm Empress 2 core) was subjected to the recommended firing cycles. Groups 3 and 4 (1 x 14 mm Empress 2 core) were veneered with the dentine material and heat-treated as per group 2. Groups 1, 2 and 3 were lapped to 800 grit silicon carbide paper on the compressive surface only and group 4 on both the compressive and tensile test surfaces. Twenty disc specimens per group were tested using the biaxial flexure test at a crosshead speed of 0.15 mm/min. Specimens were characterised using X-ray diffraction (XRD) and secondary electron imaging (SEM). Mean biaxial flexural strengths (MPa+/-SD) were group 1: 265.5+/-25.7; group 2: 251.3+/-30.2; group 3: 258.6+/-21.4 and group 4: 308.6+/-37.7. There was no statistical difference between groups 1, 2 and 3 (p>0.05), but differences for group 4 (pEmpress 2 core material and an amorphous glass and some evidence of a crystalline phase in the dentine material. CONCLUSIONS; Veneering or heat treatment of Empress 2 ceramics did not significantly affect the mean biaxial flexural strength (p>0.05) or reliability. Surface modification of the Empress 2 core material increased the mean biaxial flexural strength (p<0.05).

  13. A study on the mechanical stress relieving and safety assessment without post-weld heat treatment

    International Nuclear Information System (INIS)

    Xu Jijin; Chen Ligong; Ni Chunzhen

    2007-01-01

    For full welded body valve, the temperature of grommet cannot exceed 150 deg. C in order to prevent it from damaging and assure the tightness and the service life of valve. Therefore, post-weld heat treatment (PWHT) cannot be used to relieve the residual stresses. In this study, the effect of the mechanical stress relieving (MSR) treatment on the residual stresses was studied by the finite element method and experimental work. A pressure and time diagram of MSR treatment was established. A two-dimensional axisymmetric finite element model was used to simulate the residual stresses field. Before and after MSR treatment, the residual stresses on the outer surface were measured by the blind hole drilling method. Finally, the fracture toughness behaviors of weld zone (WZ) and heat affected zone (HAZ) were investigated in terms of crack tip opening displacement (CTOD) according to BS7448 and DNV-OS-C401 fracture toughness tests standards. The safety of the valve in active service was assessed without PWHT. Through comparison and analysis, the axial residual stresses and the hoop residual stresses on the outer surface of valve are mainly tensile. The peak value of tensile stress occurs nearer to the outer surface of the valve. MSR treatment can decrease the peak value of axial residual stresses and hoop residual stresses on the outer surface obviously and make the residual stresses distribution more uniform. The safety of the valve in active service is reliable without PWHT

  14. Synthesis of Mo5SiB2 based nanocomposites by mechanical alloying and subsequent heat treatment

    International Nuclear Information System (INIS)

    Abbasi, A.R.; Shamanian, M.

    2011-01-01

    Research highlights: → α-Mo-Mo 5 SiB 2 nanocomposite was produced after 20 h milling of Mo-Si-B powders. → Heat treatment of 5 h MAed powders led to the formation of boride phases. → Heat treatment of 10 h MAed powders led to the formation of Mo 5 SiB 2 phase. → By increasing heat treatment time, quantity of Mo 5 SiB 2 phase increased. → 5 h heat treatment of 20 h MAed powders led to the formation of Mo 5 SiB 2 -based composite. - Abstract: In this study, systematic investigations were conducted on the synthesis of Mo 5 SiB 2 -based alloy by mechanical alloying and subsequent heat treatment. In this regard, Mo-12.5 mol% Si-25 mol% B powder mixture was milled for different times. Then, the mechanically alloyed powders were heat treated at 1373 K for 1 h. The phase transitions and microstructural evolutions of powder particles during mechanical alloying and heat treatment were studied by X-ray diffractometry and scanning electron microscopy. The results showed that the phase evolutions during mechanical alloying and subsequent heat treatment are strongly dependent on milling time. After 10 h of milling, a Mo solid solution was formed, but, no intermetallic phases were detected at this stage. However, an α-Mo-Mo 5 SiB 2 nanocomposite was formed after 20 h of milling. After heat treatment of 5 h mechanically alloyed powders, small amounts of MoB and Mo 2 B were detected and α-Mo-MoB-Mo 2 B composite was produced. On the other hand, heat treatment of 10 h and 20 h mechanically alloyed powders led to the formation of an α-Mo-Mo 5 SiB 2 -MoSi 2 -Mo 3 Si composite. At this point, there is a critical milling time (10 h) for the formation of Mo 5 SiB 2 phase after heat treatment wherein below that time, boride phase and after that time, Mo 5 SiB 2 phase are formed. In the case of 20 h mechanically alloyed powders, by increasing heat treatment time, not only the quantity of α-Mo was reduced and the quantity of Mo 5 SiB 2 was increased, but also new boride

  15. Effect of Various Heat Treatment Processes on Fatigue Behavior of Tool Steel for Cold Forging Die

    Science.gov (United States)

    Jin, S. U.; Kim, S. S.; Lee, Y. S.; Kwon, Y. N.; Lee, J. H.

    Effects of various heat treatment processes, including "Q/T (quenching and tempering)", "Q/CT/T (Quenching, cryogenic treatment and tempering)", "Q/T (quenching and tempering) + Ti-nitriding" and "Q/CT/T (Cryogenic treatment and tempering) + Ti-nitriding", on S-N fatigue behavior of AISI D2 tool steel were investigated. The optical micrographs and Vicker's hardness values at near surface and core area were examined for each specimen. Uniaxial fatigue tests were performed by using an electro-magnetic resonance fatigue testing machine at a frequency of 80 Hz and an R ratio of -1. The overall resistance to fatigue tends to decrease significantly with Ti-nitriding treatment compared to those for the general Q/T and Q/CT/T specimens. The reduced resistance to fatigue with Ti-nitriding is discussed based on the microstructural and fractographic analyses.

  16. Corrosion resistance of structural material AlMg-2 in water following heat treatment and cooling

    International Nuclear Information System (INIS)

    Maman Kartaman A; Djoko Kisworo; Dedi Hariyadi; Sigit

    2005-01-01

    Corrosion tests of structural material AlMg-2 in water were carried out using autoclave in order to study the effects of heat treatment on the corrosion resistance of the material. Prior to the tests, the samples were heat-treated at temperatures of 90, 200, 300 and 500 °C and cooled in air, sand and water. The corrosion tests were conducted in water at temperature of 150 °C for 250 hours. The results showed that AlMg-2 samples were corroded although the increase of mass gain was relatively small. Heat treatment from 90 to 500 °C in sand cooling media resulted in an increase of mass gain despite that at 300 °C the increase was less than those at 200 °C and 500 °C. For water cooling media in the temperature range of 90 to 200 °C, the mass gain increased from 0.1854 g/cm 2 to 2.1204 g/cm 2 although after 200 °C it decreased to 1.8207 g/cm 2 and 1.6779 g/cm 2 respectively. For air cooling media, the mass gain was relatively constant. Based on the experiment results, it can be concluded that heat treatment and cooling did not significantly influence the corrosion resistance of material AlMg-2. The passive film Al 2 O 3 on the surface was able to protect the inner surface from further corrosion. Water media with pH range from 4 – 9 did not cause damage to passive layer formed. (author)

  17. Optimisasi Suhu Pemanasan dan Kadar Air pada Produksi Pati Talas Kimpul Termodifikasi dengan Teknik Heat Moisture Treatment (HMT (Optimization of Heating Temperature and Moisture Content on the Production of Modified Cocoyam Starch Using Heat Moisture Treatment (HMT Technique

    Directory of Open Access Journals (Sweden)

    I Nengah Kencana Putra

    2016-12-01

    Full Text Available One of the physically starch modification technique is heat-moisture treatment (HMT. This technique can increase the resistance of starch to heat, mechanical treatment, and acid during processing.  This research aimed to find out the influence of heating temperature and moisture content in the modification process of cocoyam starch  with HMT techniques on the characteristic of product, and then to determine the optimum heating temperature and moisture content in the process. The research was designed with a complete randomized design (CRD with two factors factorial experiment.  The first factor was temperature of the heating consists of 3 levels namely 100 °C, 110 °C, and 120 °C. The second factor was the moisture content of starch which consists of 4 levels, namely 15 %, 20 %, 25 %, and 30 %. The results showed that the heating temperature and moisture content significantly affected water content, amylose content and swelling power of modified cocoyam starch product, but the treatment had no significant effect on the solubility of the product. HMT process was able to change the type of cocoyam starch from type B to type C. The optimum heating temperature and water content on modified cocoyam starch production process was 110 °C and 30 % respectively. Such treatment resulted in a modified cocoyam starch with moisture content of 6.50 %, 50,14 % amylose content, swelling power of 7.90, 0.0009% solubility, paste clarity of 96.310 % T, and was classified as a type C starch.   ABSTRAK Salah satu teknik modifikasi pati secara fisik adalah teknik Heat Moisture Treatment (HMT. Teknik ini dapat meningkatkan ketahanan pati terhadap panas, perlakuan mekanik, dan asam selama pengolahan. Penelitian ini bertujuan untuk mengetahui pengaruh suhu dan kadar air pada proses modifikasi pati talas kimpul dengan teknik HMT terhadap karakteristik produk, dan selanjutnya menentukan suhu dan kadar air yang optimal dalam proses tersebut. Penelitian ini dirancang

  18. Microstructure evolution during spray rolling and heat treatment of 2124 Al

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, K.M. [Industrial Technology Department, Idaho National Laboratory, Idaho Falls, ID 83415-2050 (United States)], E-mail: kevin.mchugh@inl.gov; Lin, Y.; Zhou, Y.; Johnson, S.B.; Delplanque, J.-P.; Lavernia, E.J. [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States)

    2008-03-25

    Spray rolling is a strip-casting technology that combines elements of spray forming and twin-roll casting. It consists of atomizing molten metal with a high velocity inert gas, quenching the resultant droplets in flight, and directing the spray between mill rolls. In-flight convection heat transfer from atomized droplets and conduction heat transfer at the rolls rapidly remove the metal's latent heat. Hot deformation of the semi-solid material in the rolls results in fully consolidated, rapidly-solidified strip. Spray rolling operates at a higher solidification rate than conventional twin-roll casting and is able to process a broader range of alloys at high production rates. A laboratory-scale strip caster was constructed and used to evaluate the interplay of processing parameters and strip quality for strips up to 200 mm wide and 1.6-6.4 mm thick. This paper examines microstructure evolution during spray rolling and explores how gas-to-metal mass flow ratio influences the microstructure and mechanical properties of spray-rolled 2124 Al. The influences of solution heat treatment and cold rolling on grain structure and constituent particle spheroidization are also examined.

  19. Assessment of heat treatment of dairy products by MALDI-TOF-MS.

    Science.gov (United States)

    Meltretter, Jasmin; Birlouez-Aragon, Inès; Becker, Cord-Michael; Pischetsrieder, Monika

    2009-12-01

    The formation of the Amadori product from lactose (protein lactosylation) is a major parameter to evaluate the quality of processed milk. Here, MALDI-TOF-MS was used for the relative quantification of lactose-adducts in heated milk. Milk was heated at a temperature of 70, 80, and 100 degrees C between 0 and 300 min, diluted, and subjected directly to MALDI-TOF-MS. The lactosylation rate of alpha-lactalbumin increased with increasing reaction temperature and time. The results correlated well with established markers for heat treatment of milk (concentration of total soluble protein, soluble alpha-lactalbumin and beta-lactoglobulin at pH 4.6, and fluorescence of advanced Maillard products and soluble tryptophan index; r=0.969-0.997). The method was also applied to examine commercially available dairy products. In severely heated products, protein pre-purification by immobilized metal affinity chromatography improved spectra quality. Relative quantification of protein lactosylation by MALDI-TOF-MS proved to be a very fast and reliable method to monitor early Maillard reaction during milk processing.

  20. Intermittent cryogen spray cooling for optimal heat extraction during dermatologic laser treatment

    Science.gov (United States)

    Majaron, Boris; Svaasand, Lars O.; Aguilar, Guillermo; Nelson, J. Stuart

    2002-09-01

    Fast heat extraction is critically important to obtain the maximal benefit of cryogen spray cooling (CSC) during laser therapy of shallow skin lesions, such as port wine stain birthmarks. However, a film of liquid cryogen can build up on the skin surface, impairing heat transfer due to the relatively low thermal conductivity and higher temperature of the film as compared to the impinging spray droplets. In an attempt to optimize the cryogen mass flux, while minimally affecting other spray characteristics, we apply a series of 10 ms spurts with variable duty cycles. Heat extraction dynamics during such intermittent cryogen sprays were measured using a custom-made metal-disc detector. The highest cooling rates were observed at moderate duty cycle levels. This confirms the presence, and offers a practical way to eliminate the adverse effect of liquid cryogen build-up on the sprayed surface. On the other hand, lower duty cycles allow a substantial reduction in the average rate of heat extraction, enabling less aggressive and more efficient CSC for treatment of deeper targets, such as hair follicles.

  1. Analysis of the building system of four mills and their suitability for heat treatment pest disinfestation

    Directory of Open Access Journals (Sweden)

    Loredana Strano

    2013-09-01

    Full Text Available The last century researchers at Kansas State University demonstrated the validity of the heat treatment as a method of pest control in more than 20 mills. However factors such as the high capital investment required to heat large buildings, inadequate control of high temperatures and the risk of damage to parts of the plants or the construction materials have prevented the large-scale adoption of this technique as a viable alternative to fumigants. Today the combination of the industrialization of the food industry, the technological and structural modernization of plants and developments in heat disinfection technologies have resulted in interesting results being obtained for the use of this system in primary and secondary production processing plants, both experimentally and in practice. However, the scientific literature highlights some of the factors that limit the efficiency of the treatment. This is related to aspects of the buildings and the plants and the environment of the buildings. The structure of the buildings appear to have an enormous impact on energy consumption, because this depends on the amount of heating time and the methods that have to be used when establishing a heat treatment regime. These factors are important if the fumigation temperatures are to be reached in the shortest possible time and can affect the choice of the technique used with current fumigants, especially when this is combined with the amount and cost of the energy consumed. The aim of this work is to analyse four Sicilians mills that intend to use the heat system for fumigation and pest control in order to identify those aspects of the buildings, plant and their environment which are “critical elements” and may discourage the use of this technology. Particular attention was paid to the type of construction materials and their thermal conductivity (roof, floors and walls, the number and volume of the buildings and the distance between them, the

  2. In situ post-weld heat treatment on martensitic stainless steel turbine runners using a robotic induction heating process to control temperature distribution

    Science.gov (United States)

    Boudreault, E.; Hazel, B.; Côté, J.; Godin, S.

    2014-03-01

    A new robotic heat treatment process is developed. Using this solution it is now possible to perform local heat treatment on large steel components. Crack, cavitation and erosion repairs on turbine blades and Pelton buckets are among the applications of this technique. The proof of concept is made on a 13Cr-4Ni stainless steel designated "CA6NM". This alloy is widely used in the power industry for modern system components. Given the very tight temperature tolerance (600 to 630 °C) for post-weld heat treatment on this alloy, 13Cr-4Ni stainless steel is very well suited for demonstrating the possibilities of this process. To achieve heat treatment requirements, an induction heating system is mounted on a compact manipulator named "Scompi". This robot moves a pancake coil in order to control the temperature distribution. A simulator using thermal finite element analysis is first used for path planning. A feedback loop adjusts parameters in function of environmental conditions.

  3. In situ post-weld heat treatment on martensitic stainless steel turbine runners using a robotic induction heating process to control temperature distribution

    International Nuclear Information System (INIS)

    Boudreault, E; Hazel, B; Côté, J; Godin, S

    2014-01-01

    A new robotic heat treatment process is developed. Using this solution it is now possible to perform local heat treatment on large steel components. Crack, cavitation and erosion repairs on turbine blades and Pelton buckets are among the applications of this technique. The proof of concept is made on a 13Cr-4Ni stainless steel designated C A6NM . This alloy is widely used in the power industry for modern system components. Given the very tight temperature tolerance (600 to 630 °C) for post-weld heat treatment on this alloy, 13Cr-4Ni stainless steel is very well suited for demonstrating the possibilities of this process. To achieve heat treatment requirements, an induction heating system is mounted on a compact manipulator named S compi . This robot moves a pancake coil in order to control the temperature distribution. A simulator using thermal finite element analysis is first used for path planning. A feedback loop adjusts parameters in function of environmental conditions

  4. Effect of Heat Shock Treatment and Aloe Vera Coating to Chilling Injury Symptom in Tomato (Lycopersicon asculantum Mill.

    Directory of Open Access Journals (Sweden)

    Sutrisno

    2012-04-01

    Full Text Available This research was undertaken to determine the effect of length in heat shock and edible coating as pre-storage treatment to Chilling Injury (CI symptom reflected by ion leakage induced and quality properties in tomato (Lycopersicon asculantum Mill.. Heat Shock Treatment (HST was conducted at three different levels of length, which were, 20; 40 and 60 min. Edible coating was conducted using aloe vera gel. The result showed that HST and Aloe Vera Coating (AVC were more effective to reduce CI symptom at lower chilling storage. Prolong exposure to heated water may delay climacteric peak. The length of heat shock, AVC treatment and low temperature storage significantly affected the tomato quality parameter but not significantly different for each treatment except weight loss. HST for 20 min at ambient temperature was significantly different to other treatment.

  5. On the thermochemical conversions of hard coal pitches in the process of raising the softening point to 358-363 K

    Energy Technology Data Exchange (ETDEWEB)

    Kekin, N.A.; Belkina, T.V.; Stepanenko, M.A.; Gordienko, V.G.

    1983-09-01

    High resolution paramagnetic resonance and infrared spectroscopy are used to obtain data on the nature of changes in hydrogen content of various groups in the substances of soluble functions in raw pitch and its thermoproducts during the process of producing binders with an increased softening point of 358-363 K. It was shown that thermal treatment of pitch during the process of raising the softening point leads to enrichment of the pitch structure with aromatic hydrogen and to reduction in the structure of the hydrogen in aliphatic bonds. The basis of these conversions is the splitting off of CH/SUB/3 groups and the formation of new structures containing CH/SUB/2 groups. (11 refs.)

  6. Optimization of the heat and mechanical treatment of the Al-Zn-Mg-Li alloy

    Directory of Open Access Journals (Sweden)

    M. Stegliński

    2010-07-01

    Full Text Available In terms of high strength in relation to mass the alloys of aluminium – lithium find more and more use mainly in aircraft industry like inspacecraft. At present intensive investigations are carried out in aim of use of Al – Li in automotive industry in particular to components subject to fatigue wear. It could contribute to replace transmission’s elements made from traditional materials by aluminium - lithium alloys. However low resistance to wear due to forming of thin Al2O3 layer which is reproducing in friction contact disqualifies using aluminium alloys in friction contact. From this point of view first stage of investigation was to enhance hardness properties of the substrate by applying thermo-mechanical treatment.In this article the results of heat treatment of Al-Zn-Mg-Li alloy were presented. During investigations optimum parameters (timetemperature of the solution heat treatment were elaborated. Micro hardness on the cross-section were investigated. Phase, chemicalcomposition and morphology were determined. It was found that hardness after thermo-mechanical treatment of Al-Zn-Mg-Li is about20% higher than for AlCu4Mg1 (7075 –T6 alloy.

  7. Exploiting heat treatment effects on SMAs macro and microscopic properties in developing fire protection devices

    Science.gov (United States)

    Burlacu, L.; Cimpoeşu, N.; Bujoreanu, L. G.; Lohan, N. M.

    2017-08-01

    Ni-Ti shape memory alloys (SMAs) are intelligent alloys which demonstrate unique properties, such as shape memory effect, two-way shape memory effect, super-elasticity and vibration damping which, accompanied by good processability, excellent corrosion resistance and biocompatibility as well as fair wear resistance and cyclic stability, enabled the development of important industrial applications (such as sensors, actuators, fasteners, couplings and valves), medical applications (such as stents, bone implants, orthodontic archwires, minimal invasive surgical equipment) as well as environmental health and safety devices (anti-seismic dampers, fire safety devices). The phase transitions in Ni-Ti SMAs are strongly influenced by processing methods, chemical compositions and thermomechanical history. This paper presents a study of the effects of heat treatment on the mechanical and thermal properties of commercial Ni-Ti shape memory alloy (SMA). The experimental work involved subjecting a SMA rod to heat-treatment consisting in heating up to 500°C, 10 minutes-maintaining and water quenching. Mechanical properties were highlighted by microhardness tests while thermal characteristics were emphasized by differential scanning calorimetry (DSC). The presence of chemical composition fluctuations was checked by X-ray energy dispersive spectroscopy performed with an EDAX Bruker analyzer.

  8. Effect of Heat and Laser Treatment on Cu2S Thin Film Sprayed on Polyimide Substrate

    Science.gov (United States)

    Magdy, Wafaa; Mahmoud, Fawzy A.; Nassar, Amira H.

    2018-02-01

    Three samples of copper sulfide Cu2S thin film were deposited on polyimide substrate by spray pyrolysis using deposition temperature of 400°C and deposition time of about 45 min. One of the samples was left as deposited, another was heat treated, while the third was laser treated. The structural, surface morphological, optical, mechanical, and electrical properties of the films were investigated. X-ray diffraction (XRD) analysis showed that the copper sulfide films were close to copper-rich phase (Cu2S). Increased crystallite size after heat and laser treatment was confirmed by XRD analysis and scanning electron microscopy. Vickers hardness measurements showed that the samples' hardness values were enhanced with increasing crystallite size, representing an inverse Hall-Petch (H-P) effect. The calculated optical bandgap of the treated films was lower than that of the deposited film. Finally, it was found that both heat and laser treatment enhanced the physical properties of the sprayed Cu2S films on polyimide substrate for use in solar energy applications.

  9. Influence of heat treatment on field emission characteristics of boron nitride thin films

    International Nuclear Information System (INIS)

    Li Weiqing; Gu Guangrui; Li Yingai; He Zhi; Feng Wei; Liu Lihua; Zhao Chunhong; Zhao Yongnian

    2005-01-01

    Boron nitride (BN) nanometer thin films are synthesized on Si (1 0 0) substrates by RF reactive magnetron sputtering. Then the film surfaces are treated in the case of the base pressure below 5 x 10 -4 Pa and the temperature of 800 and 1000 deg. C, respectively. And the films are studied by Fourier transform infrared spectra (FTIR), atomic force microscopic (AFM) and field emission characteristics at different annealing temperature. The results show that the surface heat treatment makes no apparent influence on the surface morphology of the BN films. The transformations of the sample emission characteristics have to do with the surface negative electron affinity (NEA) of the films possibly. The threshold electric fields are lower for BN samples without heat-treating than the treated films, which possibly ascribed to the surface negative electron affinity effect. A threshold field of 8 V/μm and the emission current of 80 μA are obtained. The surface NEA is still presence at the heat treatment temperature of 800 deg. C and disappeared at temperature of 1000 deg. C

  10. Low-temperature synthesis of allyl dimethylamine by selective heating under microwave irradiation used for water treatment

    International Nuclear Information System (INIS)

    Tian Binghui; Luan Zhaokun; Li Mingming

    2005-01-01

    Low-temperature synthesis of allyl dimethylamine (ADA) by selective heating under microwave irradiation (MI) used for water treatment is investigated. The effect of MI, ultrasound irradiation (UI) and conventional heating on yield of ADA, reaction time and the flocculation efficiency of polydiallyl dimethylammunion chloride (PDADMAC) prepared form ADA were studied. The results show that by selective heating at low temperature, MI not only increases yield of ADA and reduces reaction time, but also greatly enhances the flocculation efficiency of PDADMAC

  11. Analytical and numerical treatment of the heat conduction equation obtained via time-fractional distributed-order heat conduction law

    Science.gov (United States)

    Želi, Velibor; Zorica, Dušan

    2018-02-01

    Generalization of the heat conduction equation is obtained by considering the system of equations consisting of the energy balance equation and fractional-order constitutive heat conduction law, assumed in the form of the distributed-order Cattaneo type. The Cauchy problem for system of energy balance equation and constitutive heat conduction law is treated analytically through Fourier and Laplace integral transform methods, as well as numerically by the method of finite differences through Adams-Bashforth and Grünwald-Letnikov schemes for approximation derivatives in temporal domain and leap frog scheme for spatial derivatives. Numerical examples, showing time evolution of temperature and heat flux spatial profiles, demonstrate applicability and good agreement of both methods in cases of multi-term and power-type distributed-order heat conduction laws.

  12. On the conjoint influence of heat treatment and lithium content on microstructure and mechanical properties of A380 aluminum alloy

    International Nuclear Information System (INIS)

    Karamouz, Mostafa; Azarbarmas, Mortaza; Emamy, Masoud

    2014-01-01

    Highlights: • T4 heat treatment and the addition of Li modify the microstructure of alloy. • Heat treatment improves the tensile properties of non-modified and modified alloys. • Fracture surfaces of modified specimens had more ductile dimples than base alloys. - Abstract: In this study, the effects of a T4 heat treatment on the microstructure and tensile properties of an A380 aluminum alloy with and without lithium (Li) additions have been investigated. Microstructural examination was carried out using optical and scanning electron microscopy, image analysis, and X-ray diffraction (XRD) analysis methods. The results showed that when the T4 heat treatment was applied, spheroidized eutectic Si particles and fragmented β-phase particles were formed. The influence of the heat treatment on the aspect ratio and average length of Si and β phases in a non-modified alloy was more noticeable than in the Li-modified. Significant improvements in tensile properties were also observed in heat-treated samples. Additionally, a fractographical analysis showed that the fracture surfaces of the Li-modified specimens with and without heat treatment had more ductile dimple and fewer brittle cleavage surfaces

  13. Effect of Post-Weld Heat Treatment on Creep Rupture Properties of Grade 91 Steel Heavy Section Welds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Leijun

    2012-11-02

    This project will conduct a systematic metallurgical study on the effect of post-weld heat treatment (PWHT) on the creep rupture properties of P91 heavy section welds. The objective is to develop a technical guide for selecting PWHT parameters, and to predict expected creep-rupture life based on the selection of heat treatment parameters. The project consists of four interdependent tasks: Experimentally and numerically characterize the temperature fields of typical post-weld heat treatment procedures for various weld and joint configurations to be used in Gen IV systems. Characterize the microstructure of various regions, including the weld fusion zone, coarse-grain heat-affected zone, and fine-grain heat affected zone, in the welds that underwent the various welding and PWHT thermal histories. Conduct creep and creep-rupture testing of coupons extracted from actual and physically simulated welds. Establish the relationship among PWHT parameters, thermal histories, microstructure, creep, and creep-rupture properties.

  14. Treatment of cellulite with a bipolar radiofrequency, infrared heat, and pulsatile suction device: a pilot study.

    Science.gov (United States)

    Wanitphakdeedecha, Rungsima; Manuskiatti, Woraphong

    2006-12-01

    Very few therapeutic options have proven effective in the treatment of cellulite. To evaluate the effectiveness and adverse effects of a bipolar radiofrequency (RF), infrared (IR) heat and pulsatile suction device for the treatment of cellulite. Twelve subjects were treated with the RF-light-based device. All subjects were treated twice weekly for a total number of eight to nine treatments. Subjects were evaluated using standardized photographs, and measurements of body weight and circumference of treatment sites at baseline, immediately after the last treatment, and four weeks and one year after the last treatment. Clinical improvement scores of comparable photographs using a quartile grading scale (0 = 75% improvement) were judged independently by two non-treating dermatologists after the series of treatment. The average body weights at baseline, immediately after the last treatment, and four weeks and one year after the complete treatment were 56.30, 56.05, 56.23, and 56.53 kg, respectively. The average circumferential reductions of the abdomen and thigh at the last treatment visit were 5.17 +/- 1.04 cm (6.32%+/- 1.82%) and 3.50 +/- 2.16 cm (6.23 +/- 3.58%), respectively. At four weeks after the last treatment, the average circumferential reductions of the abdomen and thigh were sustained at 3.17 +/- 2.75 cm (4.04%+/- 3.69%) and 3.50 +/- 2.04 cm (6.26%+/- 3.52%), respectively. At one year follow-up visit, the average circumferential reductions of the abdomen and thigh were maintained at 3.83 +/- 0.76 cm (4.64%+/- 1.15%) and 3.13 +/- 3.54 (5.50%+/- 6.12%), respectively. Average clinical improvement scores of the abdomen and thigh after the series of treatments were 0.75 (corresponding to approximately 25% improvement), and 1.75 (corresponding to approximately 50% improvement), respectively. A bipolar RF, IR heat and pulsatile suction device provides a beneficial effect on reduction of abdomen and thigh circumference, and smoothening of the cellulite.

  15. Effect of different heat treatments and disinfectants on the survival of Prototheca zopfii.

    Science.gov (United States)

    Lassa, Henryka; Jagielski, Tomasz; Malinowski, Edward

    2011-03-01

    Bovine mastitis caused by the yeast-like alga Prototheca zopfii represents a serious veterinary problem and may result in heavy economic losses to particular dairy farms. The purpose of this study was to evaluate the survival of 50 isolates of P. zopfii in milk subjected to different heat treatments and the survival of further 106 P. zopfii isolates after exposure to three classes of teat disinfectants: iodine (Dipal), quaternary ammonium compounds (Teat), and dodecylbenzenesulphonic acid (Blu-gard). Of the 50 isolates tested for thermal tolerance, 29 (58%) survived heat treatment at 62 °C for 30 s and 13 (26% of all isolates) of those survived after heat treatment at 72 °C for 15 s. None of the 106 isolates were able to withstand the in-use concentrations of the three disinfectants tested. The highest disinfectant concentrations that permitted survival of at least one isolate were dilutions: 1:1,000 for Dipal (survival rate of 52.8-57.5%), 1:100 for Teat (88.7-90.6%), and 1:10 for Blu-gard (100%). No differences in the survival rates of P. zopfii were observed with respect to the duration of exposure to disinfectant. The results of this study support the previous findings that P. zopfii may resist high-temperature treatments, including that applied in the high-temperature, short-time (HTST) pasteurization process. The obtained data also demonstrate the efficacy of the three classes of teat disinfectants against P. zopfii, with the efficacy of iodine being most pronounced. The study emphasizes the necessity of using higher temperatures in the pasteurization of raw milk to kill the Prototheca algae, as well as the particular suitability of the iodine for the control procedures of protothecal mastitis.

  16. Effect of individual or combined treatment of heat or radiation on clostridium perfringens spores

    Energy Technology Data Exchange (ETDEWEB)

    El-Zawahry, Y A; El-Fouly, M Z; Aziz, N H

    1986-01-01

    Separate treatments of high temperature had considerable effect on Cl.perfrigens spores suspended in saline solution especially at 90 and 100[sup 0]C, while 70 and 80[sup 0]C had only slight effect on the spores viabilty. The decimal reduction times (D[sub T]) were 33.7, 26, 4, 10.7 and 2.8 at 70, 80, 90 and 100[sup 0]C for NCTC 8798 strain and were 45.1, 27.1, 10.2 and 4.0 for the Egyptian strain at the same degrees of temperature respectively. Heat treatment pre-irradiation at 70 and 80[sup 0]C for 30 and 60 min decreased the viable spore numbers by about 0.5 to 3.0 log cycles, but the treatment had no effect on increasing the sensitivity of the rest spores to radiation. The decimal reduction dose (D[sub 10]-value) for the spores was almost the same as the control but there was a tendency to reduce the shoulder part in the radiation response curve especially when the spores were subjected to 80[sup 0]C for 60 min. On the other hand, irradiation pre-heat treatment with doses from 1-10 KGY was sufficient to decrease the spore numbers from 0.2 to 5.0 log cycles and had a sensitizing effect on subsequently heated spores especially those exposed to 90 and 100[sup 0]C. Meanwhile the rate of inactivation for spores exposed to 70 and 80[sup 0]C after irradiation increased only during the first ten minutes. Thereafter, the rate of inactivation was almost the same for the non-irradiated spores. The D[sub 10]-values for the spores irradiated with 10 KGY were 0.77 and 0.84 minutes for NCTC 8798 strain and Egyptian strain at 100[sup 0]C respectively and the spores were completely destroyed before 5 minutes.

  17. QUALITY IMPROVEMENT OF SECONDARY SILUMINS BY USING REFINING-MODIFYING, HEAT AND LASER TREATMENTS

    Directory of Open Access Journals (Sweden)

    I. P. Volchok

    2014-10-01

    Full Text Available Purpose. As a rule secondary silumins are characterized by lower quality than their primary analogues. During manufacture of alloys a large quantity of intermetallides, first of all on the basis of iron, in their structure is ignored. To achieve the optimum level of properties it is necessary to search for ways to adapt refining-modifying, heat and laser treatments to peculiarities of the structure of secondary Al-Si alloys. Methodology. The research was carried out by using standard methods of metallographic analysis, determination of foundry, mechanical and service properties of alloys according to rotatable plans of multifactor experiments. Findings. It was established, that refiningmodifying treatment is a required procedure during manufacture of secondary silumins as it permits to effectively influence the iron-containing phases' segregations by changing their morphology, size and distribution and to increase the effectiveness of further treatment in solid state. It was found that standard modes of heat treatment are not optimal for secondary silumins. Laser treatment has shown high effectiveness in increasing of strength, wear resistance, corrosion and cavitation resistance of secondary Al-Si alloys, and the increased iron content contributed to additional solid solution hardening. Originality. It was established, that after refining-modifying treatment the phase Al5SiFe, which crystallizes in the shape of long stretched plates transformed into phase Al15(FeMn3Si2 in skeletal or polyhedral shape. The relationship between iron content in secondary silumins and holding time during heat treatment that ensures optimum of mechanical properties was obtained. It was proved that the presence of ironcontaining intermetallides Al5SiFe results in the decrease of hardened layer's depth during laser treatment. It was established, that with increasing of iron concentration the corrosion rate of secondary silumins in 3 % NaCl + 0.1 % H2O2 and 10 % HCl

  18. Crystallite size variation of TiO_2 samples depending time heat treatment

    International Nuclear Information System (INIS)

    Galante, A.G.M.; Paula, F.R. de; Montanhera, M.A.; Pereira, E.A.; Spada, E.R.

    2016-01-01

    Titanium dioxide (TiO_2) is an oxide semiconductor that may be found in mixed phase or in distinct phases: brookite, anatase and rutile. In this work was carried out the study of the residence time influence at a given temperature in the TiO_2 powder physical properties. After the powder synthesis, the samples were divided and heat treated at 650 °C with a ramp up to 3 °C/min and a residence time ranging from 0 to 20 hours and subsequently characterized by x-ray diffraction. Analyzing the obtained diffraction patterns, it was observed that, from 5-hour residence time, began the two-distinct phase coexistence: anatase and rutile. It also calculated the average crystallite size of each sample. The results showed an increase in average crystallite size with increasing residence time of the heat treatment. (author)

  19. Effect of heat treatment on the corrosion behaviour of Al-Zn alloys in seawater

    International Nuclear Information System (INIS)

    Siti Radiah Mohd Kamarudin; Muhamad Daud; Nur Ubaidah Saidin; Zaifol Samsu

    2010-01-01

    A study has been carried out to investigate the effect of heat treatment on the corrosion behaviour of Al-Zn alloys in seawater environment. The microstructure, potential and current capacity of the samples were studied. Open circuit potential (OCP) of 96 hours was measured against saturated calomel electrode (SCE) and estimating current capacity of the alloys were calculated by using protective current generated from the capacity test. For the microstructure study, optical microscope is used to examine the surface morphology before and after test. The results show that the heat treated samples of 2 hours at 550 degree Celsius and variation in alloys composition affected the values of alloys OCP, current capacity and microstructure. (author)

  20. Dual Microstructure Heat Treatment of a Nickel-Base Disk Alloy

    Science.gov (United States)

    Gayda, John

    2001-01-01

    Existing Dual Microstructure Heat Treat (DMHT) technology was successfully applied to Alloy 10, a high strength, nickel-base disk alloy, to produce a disk with a fine grain bore and coarse grain rim. Specimens were extracted from the DMHT disk and tested in tension, creep, fatigue, and crack growth using conditions pertinent to disk applications. These data were then compared with data from "traditional" subsolvus and supersolvus heat treatments for Alloy 10. The results showed the DMHT disk to have a high strength, fatigue resistant bore comparable to that of subsolvus Alloy 10. Further, creep resistance of the DMHT rim was comparable to that of supersolvus Alloy 10. Crack growth resistance in the DMHT rim, while better than that for subsolvus, was inferior to that of supersolvus Alloy 10. The slow cool at the end of the DMHT conversion and/or the subsolvus resolution step are thought to be responsible for degrading rim DMHT crack growth resistance.

  1. Effect of technological procedures on the crack resistance of nickel alloy welded joints under heat treatment

    International Nuclear Information System (INIS)

    Bagdasarov, Yu.S.; Sorokin, L.I.; Yakushin, B.F.; Moryashchev, S.F.

    1983-01-01

    Comparison of the efficiency of some technological procedures directed to the increase of crack resistance of KhN50MBKTYUR (EhP99) alloy welded joints under heat treatment was conducted. Welded joints were manufactured by the methods of electron beam welding, laser welding, automatic argon-arc welding. The latter was conducted by conventional technology as well as with electromagnetic mixing of liquid metal of welding bath, with compulsory cooling of weld matal, with pulse arc. It is shown that the high fracture resistance of welded joints, manufactured by electron beam and laser welding is achieved by combination of high mechanical properties of heat affected zone metal and reduced elastic potential energy margin of residual welding stresses (as compared to argon-arc welding)

  2. Surface hardening using cw CO2 laser: laser heat treatment, modelation, and experimental work

    Science.gov (United States)

    Muniz, German; Alum, Jorge

    1996-02-01

    In the present work are given the results of the application of laser metal surface hardening techniques using a cw carbon dioxide laser as an energy source on steel 65 G. The laser heat treatment results are presented theoretically and experimentally. Continuous wave carbon dioxide laser of 0.6, 0.3, and 0.4 kW were used. A physical model for the descriptions of the thermophysical laser metal interactions process is given and a numerical algorithm is used to solve this problem by means of the LHT code. The results are compared with the corresponding experimental ones and a very good agreement is observed. The LHT code is able to do predictions of transformation hardening by laser heating. These results will be completed with other ones concerning laser alloying and cladding presented in a second paper.

  3. Study of secondary recrystallization in grain-oriented steel treated under dynamical heat treatment conditions

    Directory of Open Access Journals (Sweden)

    V. Stoyka

    2009-04-01

    Full Text Available The present study was made to investigate secondary recrystallization in grain-oriented steels annealed at short time temperature exposures with application of dynamical heating. The investigated GO steels for experiments were taken from one industrial line after final cold rolling reduction and subsequent box annealing. It was shown that application of short time heat treatment conditions could lead to complete abnormal grain growth in the investigated GO steel. The texture and microstructure obtained in the laboratory treated material is similar to that observed in the same GO steel taken after industrial final box-annealing. However, some “parasitic” grains were observed in the secondary recrystallized matrix of the laboratory treated GO steel. These “parasitic” grains possess the unwanted from magnetic properties point of view {111} orientation components.

  4. Seasonal heat stress: Clinical implications and hormone treatments for the fertility of dairy cows.

    Science.gov (United States)

    De Rensis, F; Garcia-Ispierto, I; López-Gatius, F

    2015-09-15

    Heat stress has consequences on both the physiology and reproductive performance of cows, but the most dramatic effect for dairy producers is the decrease produced in fertility. The effects of heat stress on fertility include an increased number of days open, reduced conception rate, and larger number of cows suffering different types of anestrus. Once becomes pregnant, heat stress affects also the reproductive success of the cow through its direct effects on the ovary, uterus, gametes, embryo, and early fetus. This article reviews current knowledge of the effects of heat stress on fertility in dairy cows and the hormonal strategies used to mitigate these effects at the farm level. Administration of GnRH at the moment of artificial insemination can improve the conception rate. Breeding synchronization protocols for fixed-time insemination may reduce the calving conception interval and the number of services per conception. Progesterone-based protocols seem resolve better the reproductive disorders related to a hot environment (anestrus) than GnRH-based protocols. The use of combinations of GnRH, eCG, and hCG in progesterone-based protocols can improve results. Progesterone supplementation during the late embryonic and/or early fetal period would be useful in curtailing pregnancy losses, mainly in single pregnancies, whereas a more positive effect of treatment with GnRH than progesterone has been found in twin pregnancies. Melatonin therapy is emerging as a promising strategy to improve the natural reproductive performance of cows suffering conditions of heat stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Increase of efficiency of plant materials heat treatment in tubular reactors

    Directory of Open Access Journals (Sweden)

    A. V. Golubkovich

    2016-01-01

    Full Text Available In agriculture products of pyrolysis of plant materials in the form of waste of the main production can be applied as a source of heat and electric power. Besides, their use prevents ecological pollution of the soil and the atmosphere. Pyrolysis plants can be used for work with tubular reactors anywhere. Due to them farmers can dry grain, using waste heat of diesel generators, heatgenerators, boiler plants and receiving thus gaseous products, liquid and firm fractions. A technology based on cyclic and continuous plant mass movement by a piston in a pipe from a loading site to a place of unloading of a firm phase consistently through cameras of drying, pyrolysis, condensation of gaseous products. Exhaust furnace gases with a temperature up to 600 degrees Celsius are given countercurrent material movement from a power equipment. The gaseous, liquid and firm products from the pyrolysis camera are used for heat and electric power generation. Calculation of parameters of subdrying and pyrolysis cameras is necessary for effective and steady operation of the tubular reactor. The authors determined the speed of raw materials movement, and also duration of drying and pyrolysis in working chambers. An analysis of a simplified mathematical model of process was confirmed with results of experiments. Models of heat treatment of wet plant materials in tubular reactors are worked out on a basis of equality of speeds of material movement in the reactor and distribution of a temperature front in material on radius. The authors defined estimated characteristic for determination of tubular reactor productivity and size of heat, required for drying and pyrolysis.

  6. Regional waste treatment facilities with underground monolith disposal for all low-heat-generating nuclear wastes

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1982-01-01

    An alternative system for treatment and disposal of all ''low-heat-generating'' nuclear wastes from all sources is proposed. The system, Regional Waste Treatment Facilities with Underground Monolith Disposal (RWTF/UMD), integrates waste treatment and disposal operations into single facilities at regional sites. Untreated and/or pretreated wastes are transported from generation sites such as reactors, hospitals, and industries to regional facilities in bulk containers. Liquid wastes are also transported in bulk after being gelled for transport. The untreated and pretreated wastes are processed by incineration, crushing, and other processes at the RWTF. The processed wastes are mixed with cement. The wet concrete mixture is poured into large low-cost, manmade caverns or deep trenches. Monolith dimensions are from 15 to 25 m wide, and 20 to 60 m high and as long as required. This alternative waste system may provide higher safety margins in waste disposal at lower costs

  7. Ultrasonic attenuation as a function of heat treatment and grain size in 79Ni--6Mo--15Fe alloy

    International Nuclear Information System (INIS)

    Gieske, J.H.

    1978-03-01

    A pulse echo ultrasonic technique was used to measure the attenuation coefficient for 79Ni-6Mo-15Fe alloy specimens. The attenuation coefficient was determined using a 25 MHz ultrasonic transducer for specimens which had undergone different time-temperature heat treatments. The ultrasonic attenuation data versus heat treat time was used to assess grain size growth in the specimens

  8. Effect of Post-weld Heat Treatment on the Mechanical Properties of Supermartensitic Stainless Steel Deposit

    Science.gov (United States)

    Zappa, Sebastián; Svoboda, Hernán; Surian, Estela

    2017-02-01

    Supermartensitic stainless steels have good weldability and adequate tensile property, toughness and corrosion resistance. They have been developed as an alternative technology, mainly for oil and gas industries. The final properties of a supermartensitic stainless steel deposit depend on its chemical composition and microstructure: martensite, tempered martensite, ferrite, retained austenite and carbides and/or nitrides. In these steels, the post-weld heat treatments (PWHTs) are usually double tempering ones, to ensure both complete tempering of martensite and high austenite content, to increase toughness and decrease hardness. The aim of this work was to study the effect of post-weld heat treatments (solution treatment with single and double tempering) on the mechanical properties of a supermartensitic stainless steel deposit. An all-weld metal test coupon was welded according to standard ANSI/AWS A5.22-95 using a GMAW supermartensitic stainless steel metal cored wire, under gas shielding. PWHTs were carried out varying the temperature of the first tempering treatment with and without a second tempering one, after solution treatment. All-weld metal chemical composition analysis, metallurgical characterization, hardness and tensile property measurements and Charpy-V tests were carried out. There are several factors which can be affected by the PWHTs, among them austenite content is a significant one. Different austenite contents (0-42%) were found. Microhardness, tensile property and toughness were affected with up to 15% of austenite content, by martensite tempering and carbide precipitation. The second tempering treatment seemed not to have had an important effect on the mechanical properties measured in this work.

  9. THE INFLUENCE OF HEAT TREATMENT WITH THE LIQUID PHASE ON FORMATION OF A MICROSTRUCTURE OF EUTECTIC Al-Si-ALLOY

    Directory of Open Access Journals (Sweden)

    A. Anikin

    2015-01-01

    Full Text Available The effect of heat treatment on the structure of the eutectic Al-Si-alloy, a theoretical substantiation process based on thermal analyzer and cooked microstructures was presented in this paper.

  10. Influence of Solution Heat Treatment on Structure and Mechanical Properties of ZnAl22Cu3 Alloy

    Directory of Open Access Journals (Sweden)

    Michalik R.

    2016-09-01

    Full Text Available The influence of solution heat treatment at 385°C over 10 h with cooling in water on the structure, hardness and strength of the ZnAl22Cu3 eutectoid alloy is presented in the paper. The eutectoid ZnAl22Cu3 alloy is characterized by a dendritic structure. Dendrites are composed of a supersaturated solid solution of Al in Zn. In the interdendritic spaces a eutectoid mixture is present, with an absence of the ε (CuZn4 phase. Solution heat treatment of the ZnAl22Cu3 alloy causes the occurrence of precipitates rich in Zn and Cu, possibly ε phase. Solution heat treatment at 385°C initially causes a significant decrease of the alloy hardness, although longer solution heat treatment causes a significant increase of the hardness as compared to the as-cast alloy.

  11. Effects of Two-stage Heat Treatment on Delayed Coke and Study of Their Surface Texture Characteristics

    Science.gov (United States)

    Im, Ui-Su; Kim, Jiyoung; Lee, Seon Ho; Lee, Byung-Rok; Peck, Dong-Hyun; Jung, Doo-Hwan

    2017-12-01

    In the present study, surface texture features and chemical properties of two types of cokes, made from coal tar by either 1-stage heat treatment or 2-stage heat treatment, were researched. The relationship between surface texture characteristics and the chemical properties was identified through molecular weight distribution, insolubility of coal tar, weight loss with temperature increase, coking yield, and polarized light microscope analysis. Rapidly cleared anisotropy texture in cokes was observed in accordance with the coking temperature rise. Quinoline insolubility and toluene insolubility of coal tar increased with a corresponding increases in coking temperature. In particular, the cokes produced by the 2-stage heat treatment (2S-C) showed surface structure of needle cokes at a temperature approximately 50°C lower than the 1-stage heat treatment (1S-C). Additionally, the coking yield of 2S-C increased by approximately 14% in comparison with 1S-C.

  12. Effect of heat treatment on microstructure, mechanical properties and erosion resistance of cast 23-8-N nitronic steel

    International Nuclear Information System (INIS)

    Kumar, Avnish; Sharma, Ashok; Goel, S.K.

    2015-01-01

    Effects of heat treatment on microstructure, mechanical properties and erosion behavior of cast 23-8-N nitronic steel were studied. A series of heat treatments were carried out in the temperature range of 1180–1240 °C to observe the effect on microstructure. Optimum heat treatment cycle was obtained at 1220 °C for holding time of 150 min, which leads to dissolution of carbides, formation of equiaxed grains and twins. Heat treatment has shown improvement in tensile strength, toughness, impact strength and work hardening capacity, however at the cost of marginal reduction in hardness and yield strength. This resulted in improvement of erosion resistance of cast 23-8-N nitronic steel. The microstructures, fractured surfaces and phases were studied by optical microscopy, field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analysis respectively

  13. Enhancing the mechanical properties of electrospun polyester mats by heat treatment

    Directory of Open Access Journals (Sweden)

    M. Kancheva

    2015-01-01

    Full Text Available Microfibrous materials with a targeted design based on poly(L-lactic acid (PLA and poly(ε-caprolactone (PCL were prepared by electrospinning and by combining electrospinning and electrospraying. Several approaches were used: (i electrospinning of a common solution of the two polymers, (ii simultaneous electrospinning of two separate solutions of PLA and PCL, (iii electrospinning of PLA solution in conjunction with electrospraying of PCL solution, and (iv alternating layer-by-layer deposition by electrospinning of separate PLA and PCL solutions. The mats were heated at the melting temperature of PCL (60°", thus achieving melting of PCL fibers/particles and thermal sealing of the fibers. The mats subjected to thermal treatment were characterized by greater mean fiber diameters and reduced values of the water contact angle compared to the pristine mats. Heat treatment of the mats affected their thermal stability and led to an increase in the crystallinity degree of PLA incorporated in the mats, whereas that of PCL was reduced. All mats were characterized by enhanced mechanical properties after thermal treatment as compared to the non-treated fibrous materials.

  14. Heat applied chitosan treatment on hardwood chips to improve physical and mechanical properties of particleboard

    Directory of Open Access Journals (Sweden)

    Mehmet Altay Basturk

    2012-11-01

    Full Text Available High-heat treatment after surface application of chitosan was used in an effort to improve physical and mechanical performances of particleboard. Particleboard is mainly used in the furniture industry and also used as a home decoration material; however, it has a poor dimensional stability. In this work, hardwood chips were obtained from a commercial plant; half of the chips were used for the control panels without chitosan treatment, and the other half were treated with chitosan acetate solutions (2% wt. Those chitosan-treated particles were also exposed to extra high-heat (140oC treatment for 90 minutes to convert chitosan acetate back to chitin. Liquid phenol-formaldehyde resin was sprayed onto dry particles at a level of 6 and 7% (wt based upon oven-dry weight. The mat was pressed (200oC for 11 minutes to form 19 mm thickness and a target of 0.63 g cm-3 density panels. Thickness swelling, linear expansion, and water gain of the treated panels were reduced over untreated panels during a 24-hour water-soak test. In addition, chitosan-treated panels showed better internal bond strength than control panels. Static bending test results showed a negative effect for the chitosan treated particleboard.

  15. Heat treatment versus properties studies associated with the Inconel 718 PBF acoustic filters

    International Nuclear Information System (INIS)

    Smolik, G.R.; Reuter, W.G.

    1975-01-01

    PBF acoustic filter Unit No. 1 cracked when heat treatment was attempted. The effects of prior thermal cycling, solution anneal temperature, and cooling rate from solution anneals were investigated. The investigations concerned influences of the above variables upon both 1400 0 F stress rupture solution-annealed properties and room temperature age-hardened properties. 1400 0 F stress rupture properties were of interest to assist the prevention of cracking during heat treatments. Room temperature age-hardened properties were needed to ensure that design requirement would be provided. Prior thermal cycling was investigated to determine if extra thermal cycles would be detrimental to the repaired filter. Slow furnace cools were considered as a means of reducing thermal stresses. Effects of solution annealing at 2000 and 1900 0 F were also determined. Test results showed that slow cooling rates would not only reduce thermal stresses but also improve 1400 0 F ductility. A modified aging treatment was established which provided the required 145 ksi room temperature yield strength for the slowly cooled material. Prior cooling did not degrade final age-hardened room temperature tensile or impact properties

  16. Modified heat treatment for lower temperature improvement of the mechanical properties of two ultrahigh strength low alloy steels

    Science.gov (United States)

    Tomita, Yoshiyuki; Okabayashi, Kunio

    1985-01-01

    In the previous papers, a new heat treatment for improving the lower temperature mechanical propertise of the ultrahigh strength low alloy steels was suggested by the authors which produces a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite through isothermal transformation at 593 K for a short time followed by water quenching (after austenitization at 1133 K). In this paper, two commercial Japanese ultrahigh strength steels, 0.40 pct C-Ni-Cr-Mo (AISI 4340 type) and 0.40 pct C-Cr-Mo (AISI 4140 type), have been studied to determine the effect of the modified heat treatment, coupled above new heat treatment with γ ⇆ α' repctitive heat treatment, on the mechanical properties from ambient temperature (287 K) to 123 K. The results obtained for various test temperatures have been compared with those for the new heat treatment reported previously and the conventional 1133 K direct water quenching treatment. The incorporation of intermediate four cyclic γ ⇆ α' repctitive heat treatment steps (after the initial austenitization at 1133 K and oil quenching) into the new heat treatment reported previously, as compared with the conventional 1133 K direct water quenching treatment, significantly improved 0.2 pct proof stress as well as notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel at similar fracture ductility levels from 287 to 123 K. Also, this heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved both 0.2 pct proof stress and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel with increased fracture ductility at 203 K and above. The microstructure consists of mixed areas of ultrafine grained martensite, within which is the refined blocky, highly dislocated structure, and the second phase lower bainite (about 15 vol pct), which appears in acicular form and partitions prior austenite grains. This newly developed heat treatment makes it possible to modify

  17. Phase separation of cesium from lead borosilicate glass by heat treatment under a reducing atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhanglian; Okada, Takashi, E-mail: t-okada@u-fukui.ac.jp; Nishimura, Fumihiro; Yonezawa, Susumu

    2016-11-05

    Highlights: • Cesium was phase separated from lead borosilicate glass under a reductive atmosphere. • The phase separation occurred on the glass surface that was in contact with the gas. • The leachability of cesium was enhanced by the phase separation. • The degree of such enhancement varied depending on the heat treatment conditions. - Abstract: A phase-separation technique for removing sodium from glass using a heat-treatment method under a reducing atmosphere was previously developed for sodium recovery from waste glass. In this study, this technique was applied to cesium-containing lead borosilicate glass to concentrate the cesium in phase-separated sodium-rich materials for efficient cesium extraction. The theoretical phase-separation temperature of the sodium-rich phase was simulated by thermodynamic equilibrium calculations and was predicted to occur below 700 °C for lead borosilicate glass. Experimentally, a simulated lead borosilicate glass was melted at 1000 °C and subsequently annealed below 700 °C under a CO-containing reducing atmosphere. The phase separation of cesium was found to occur with sodium enrichment on the glass surface that was in contact with the gas phase, promoting cesium extraction from the treated glass using water. The cesium extraction efficiency was affected by the surface area of the treated glass that was in contact with water, and under the examined conditions, the cesium extraction efficiency was up to 66%. Phase separation using reductive heat treatment, combined with a water leaching technique, is suggested to be effective for extracting cesium incorporated in borosilicate glass waste.

  18. Application of heat treatment and dispersive strengthening concept in interlayer deposition to enhance diamond film adherence

    Energy Technology Data Exchange (ETDEWEB)

    Lin Chiiruey [Tatung Inst. of Technol., Taipei (Taiwan, Province of China). Dept. of Mech. Eng.; Kuo Chengtzu; Chang Rueyming [Institute of Materials Science and Engineering, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30050 (Taiwan, Province of China)

    1997-10-31

    Two different deposition processes were carried out to enhance adherence of diamond films on WC+3-5%Co substrate with Ti-Si as the interlayer. One process can be called two-step diamond deposition process. Another process can be called interlayer heat treatment process. Diamond films were deposited by a microwave plasma chemical vapor deposition system. Ti and Si interlayer are deposited by DC sputter and an E-gun, respectively. Film morphologies, interface structure and film quality were examined by SEM, XRD, Auger electron spectroscopy and Raman spectroscopy. The residual stresses and adhesion strengths of the films were determined by Raman spectroscopy and indentation adhesion testing, respectively. Comparing the regular one-step diamond deposition process with the present two different new processes, the average dP/dX values, which are a measure of the adherence of the film, are 354 kgf/mm, 494 kgf/mm and 787 kgf/mm, respectively. In other words, the interlayer heat treatment process gives the best film adherence on average. For the two-step diamond deposition process, the interlayer thickness and the percent diamond surface coverage of the first diamond deposition step are the main parameters, and there exists an optimum Ti thickness and percent diamond coverage for the best film adherence. The main contribution to better film adherence is not a large difference in residual stress, but is due to the following reasons. The interlayer heat treatment can transform amorphous Si to polycrystalline Si, and may form strong TiC and SiC bonding. The polycrystalline Si and the diamond particles from the first diamond deposition step can be an effective seeds to enhance diamond nucleation. (orig.) 11 refs.

  19. The Effect of Heat Treatment on Physical, Chemical and Structural Properties of Calcium Sulfate Based Scaffolds

    Directory of Open Access Journals (Sweden)

    Hakan OFLAZ

    2017-03-01

    Full Text Available 3D printed calcium sulfate (CS is a promising material for on custom bone substitutes. Since it dissolves easily in body fluids, manufactured samples require to being improved to reduce solubility.  The main aim of this study was reducing the dissolubility of CS based samples by using sintering and investigating the effect of heat treatment on their physical, chemical and structural properties. To observe the effect of heat treatment on samples, contact angles were measured, X-Ray diffraction analysis (XRD was performed, and scanning electron microscope (SEM micrographs were captured before and after the sintering process, and the results were compared. Furthermore, sintered and non-sintered samples were soaked in phosphate buffered saline (PBS to observe the impact of sintering on the solubility of the material. Also, three different pore sized scaffolds were manufactured to test the limits of the 3D printer for manufacturing of scaffolds with open pores. Sintering process results in a volume reduction and according to SEM results, CS grains were fused together after heat treatment. Although non-sintered CS sample starts to dissolve in high rate and nearly 1/3 of the sample was at the bottom of the glass in a matter of minutes, sintering creates more rigid structure and there were not visible dissolution in PBS at the end of a week. The contact angle of samples cannot be measured, so it can be concluded that 3D printed material showed a super-hydrophilic property. XRD diagram suggested that there is not any new phase created in the printing and sintering processes except related hydrates of CS. As a result of the 3D printing, 500 µm, 750 µm and 1000 µm pore sized scaffolds were manufactured, successfully. However, it was seen that 500 µm pores could not be open by using depowdering after the printing process.

  20. Biocompatible water softening system using cationic protein from moringa oleifera extract

    Science.gov (United States)

    Nisha, R. R.; Jegathambal, P.; Parameswari, K.; Kirupa, K.

    2017-10-01

    In developing countries like India, the deciding factors for the selection of the specific water purification system are the flow rate, cost of implementation and maintenance, availability of materials for fabrication or assembling, technical manpower, energy requirement and reliability. But most of them are energy and cost intensive which necessitate the development of cost-effective water purification system. In this study, the feasibility of development of an efficient and cost-effective water purifier using Moringa oleifera cationic protein coated sand column to treat drinking water is presented. Moringa oleifera seeds contain cationic antimicrobial protein which acts as biocoagulant in the removal of turbidity and also aids in water softening. The main disadvantage of using Moringa seeds in water purification is that the dissolved organic matter (DOM) which is left over in the water contributes to growth of any pathogens that come into contact with the stored water. To overcome this limitation, the Moringa oleifera cationic protein coated sand (MOCP c-sand) is prepared in which the flocculant and antimicrobial properties of the MOCP are maintained and the DOM to be rinsed away. The efficiency of MOCP c-sand in removing suspended particles and reducing total hardness (TH), chloride, total dissolved solids (TDS), electrical conductivity (EC) was also studied. Also, it is shown that the functionalized sand showed the same treatment efficiency even after being stored dry and in dehydrated condition for 3 months. This confirms MOCP c-sand's potential as a locally sustainable water treatment option for developing countries since other chemicals used in water purification are expensive.