Relevant bibliographies by topics / Isothermic transformation diagrams

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Academic literature on the topic 'Isothermic transformation diagrams'

Author: Grafiati
Published: 4 June 2021
Last updated: 6 February 2022

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Journal articles on the topic "Isothermic transformation diagrams"

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Nürnberger, Florian, Mirko Schaper, Friedrich-Wilhelm Bach, Iryna Mozgova, Kostjantyn Kuznetsov, Anna Halikova, and Olga Perederieieva. "Prediction of Continuous Cooling Diagrams for the Precision Forged Tempering Steel 50CrMo4 by Means of Artificial Neural Networks." Advances in Materials Science and Engineering 2009 (2009): 1–10. http://dx.doi.org/10.1155/2009/582739.

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Quenching and tempering of precision forged components using their forging heat leads to reduced process energy and shortens the usual process chains. To design such a process, neither the isothermal transformation diagrams (TTT) nor the continuous cooling transformation (CCT) diagrams from literature can be used to predict microstructural transformations during quenching since the latter diagrams are significantly influenced by previous deformations and process-related high austenitising temperatures. For this reason, deformation CCT diagrams for several tempering steels from previous works have been investigated taking into consideration the process conditions of precision forging. Within the scope of the present work, these diagrams are used as input data for predicting microstructural transformations by means of artificial neural networks. Several artificial neural network structures have been examined using the commercial software MATLAB. Predictors have been established with satisfactory capabilities for predicting CCT diagrams for different degrees of deformation within the analyzed range of data.
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Polevoi, E. V., Yu N. Simonov, N. A. Kozyrev, R. A. Shevchenko, and L. P. Bashchenko. "Phase and structural transformations when forming a welded joint from rail steel. Report 2. Isothermal diagram of decomposition of supercooled austenite of R350LHT rail steel." Izvestiya. Ferrous Metallurgy 64, no. 4 (June 4, 2021): 266–72. http://dx.doi.org/10.17073/0368-0797-2021-4-266-272.

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An isothermal diagram of decomposition of supercooled austenite of R350LHT steel was constructed based on the results of dilatometric, metallographic and hardness analysis of this decomposition during continuous cooling and under isothermal conditions. When comparing the thermokinetic and isothermal diagrams, it was found that the thermokinetic diagram plotted during continuous cooling shifts downward and to the right in comparison with the isothermal diagram. This result is fully consistent with the known regularities. During the research, the critical points of R350LHT steel were determined: Ас1 = 711 °С; Мn = 196 °С. This isothermal diagram was used to determine the temperature of the minimum stability of overcooled austenite, which was 500 °C. Under isothermal conditions, pearlite-type structures appear in the temperature range from 700 to 600 °C. At 550 °C, a mixture of pearlitic and bainitic structures is formed. In the temperature range from 500 to 250 °C, bainitic structures are formed: at 500 – 400 °C – upper bainite; at 350 ° C – a mixture of upper and lower bainite; at 300 – 250 °С – lower bainite. Almost in the entire studied temperature range of overcooled austenite isothermal decomposition, an increase in the hardness of the transformation products is observed with a decrease in the holding temperature from 246 HV (at 700 °C) to 689 HV (at 250 °C). However, at a temperature of 500 °C, a slight drop in hardness occurs, which is apparently caused by the appearance of retained austenite during the development of bainitic transformation.
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Irani, Missam, Sukhwan Chung, Mincheol Kim, Kwangoh Lee, and Mansoo Joun. "Adjustment of Isothermal Transformation Diagrams Using Finite-Element Optimization of the Jominy Test." Metals 10, no. 7 (July 10, 2020): 931. http://dx.doi.org/10.3390/met10070931.

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A practical method for adjusting and optimizing isothermal transformation (IT) diagrams using the Jominy test is presented. The method is based on a finite-element optimization procedure, which iteratively minimizes the error between the target phase fractions and the corresponding finite-element solutions at the sample points using an optimization tool. A standard Jominy test of AISI 52100 bearing steel is used to investigate the feasibility and reliability of the method. Three optimization parameters for each IT diagram curve are mathematically applied to the modified Kirkaldy model. These parameters are the design variables in the optimization. The curves obtained from the modified Kirkaldy model are used as the initial guesses in the optimization and they approach the experimental IT diagram by minimizing the error. Good agreement is observed between the optimized diagram and the experimental diagram reported in the literature. The predicted phase fractions using the experimental IT diagram, the IT diagram obtained from the modified Kirkaldy model, and those obtained from the optimized model are compared and demonstrate that the adjustment or optimization procedure significantly improves the accuracy of the predicted phase fraction of the model. The applicability of the method is investigated in a practical case study.
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Mioković, T., J. Schwarzer, V. Schulze, O. Vöhringer, and D. Löhe. "Description of short time phase transformations during the heating of steels based on high-rate experimental data." Journal de Physique IV 120 (December 2004): 591–98. http://dx.doi.org/10.1051/jp4:2004120068.

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During surface hardening of steels like laser hardening, rapid thermal changes are imposed to the material. The modelling of these hardening processes allows the determination of time-dependent temperature fields and phase transformations within the affected zones. While there are many investigations on the transformation behaviour during cooling, there is a lack of data concerning the transformation during heating at very high heating rates. Therefore, experiments simulating the fast temperature changes are necessary to implement the effects of short time phase transformation during hardening into simulation. In this paper the effect of heating rates up to 10000 K/s on the austenitizing behaviour of the steel AISI 4140 (German grade 42CrMo4) are presented and described using an Avrami-function. The results obtained are summarized in time-temperature-transformation diagrams for continuous heating and isothermal time-temperature-transformation diagrams which may be used as input data for the simulation.
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Kessler, O., R. von Bargen, Fabian Hoffmann, and H. W. Zoch. "Continuous Cooling Transformation (CCT) Diagram of Aluminium Alloy Al-4.5Zn-1Mg." Materials Science Forum 519-521 (July 2006): 1467–72. http://dx.doi.org/10.4028/www.scientific.net/msf.519-521.1467.

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Age hardening is one of the most important processes to strengthen aluminium alloys. It usually consists of the steps solution annealing, quenching and aging. For heat treatment simulations as well as for the appropriate choice of quenching processes in heat treatment shops, knowledge of the temperature- and time-dependent precipitation behaviour during continuous cooling is required. Quenching should happen as fast as necessary to reach high strengths, but also as slow as possible, to reduce residual stresses and distortion. This optimal quenching rate of an aluminium component depends on its chemical composition, initial microstructure and solution annealing parameters as well as on its dimensions. Unfortunately continuous cooling transformation (CCT) diagrams of aluminium alloys do almost not exist. Instead isothermal transformation (IT) diagrams or given average quenching rates are used to estimate quenching processes, but they are not satisfying neither for heat treatment simulations nor for heat treatment shops. Thermal analysis, especially Differential Scanning Calorimetry (DSC) provides an approach for CCT-diagrams of aluminium alloys, if the relevant quenching rates can be realized in the DSCequipment. The aluminium alloy Al-4.5Zn-1Mg (7020) is known for its relatively low quenching sensitivity as well as for its technical importance. The complete CCT-diagram of 7020 with cooling rates from a few K/min to some 100 K/min has been recorded. Samples have been solution annealed and quenched with different cooling rates in a high speed DSC. The resulting precipitation heat peaks during cooling have been evaluated for temperature and time of precipitation start, as well as their areas as a measure for the precipitate amount. Quenched samples have been further investigated regarding their microstructure by light and electron microscopy, hardness after aging and precipitation behaviour during re-heating in DSC. The CCT-diagram correlated very well with the microstructure, hardness and re-heating results. A critical cooling rate with no detectable precipitation during continuous cooling 155 K/min could be determined for 7020. A model to integrate the CCT-diagram in heat treatment simulation of aluminium alloys is under development.
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Umemoto, Minoru, and Imao Tamura. "Computer simulation of isothermal transformation diagrams in steels." Bulletin of the Japan Institute of Metals 25, no. 6 (1986): 497–504. http://dx.doi.org/10.2320/materia1962.25.497.

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Bahmani, M., and R. Elliott. "Isothermal transformation diagrams for alloyed ductile cast iron." Materials Science and Technology 10, no. 12 (December 1994): 1050–56. http://dx.doi.org/10.1179/mst.1994.10.12.1050.

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Piekarska, W. "Modelling and Analysis of Phase Transformations and Stresses in Laser Welding Process / Modelowanie I Analiza Przemian Fazowych I Naprężeń W Procesie Spawania Laserowego." Archives of Metallurgy and Materials 60, no. 4 (December 1, 2015): 2833–42. http://dx.doi.org/10.1515/amm-2015-0454.

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The work concerns the numerical modelling of structural composition and stress state in steel elements welded by a laser beam. The temperature field in butt welded joint is obtained from the solution of heat transfer equation with convective term. The heat source model is developed. Latent heat of solid-liquid and liquid-gas transformations as well as latent heats of phase transformations in solid state are taken into account in the algorithm of thermal phenomena. The kinetics of phase transformations in the solid state and volume fractions of formed structures are determined using classical formulas as well as Continuous-Heating-Transformation (CHT) diagram and Continuous-Cooling-Transformation (CCT) diagram during welding. Models of phase transformations take into account the influence of thermal cycle parameters on the kinetics of phase transformations during welding. Temporary and residual stress is obtained on the basis of the solution of mechanical equilibrium equations in a rate form. Plastic strain is determined using non-isothermal plastic flow with isotropic reinforcement, obeying Huber-Misses plasticity condition. In addition to thermal and plastic strains, the model takes into account structural strain and transformation plasticity. Changing with temperature and structural composition thermophysical parameters are included into constitutive relations. Results of the prediction of structural composition and stress state in laser butt weld joint are presented.
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Uhm, Sang Ho, Joo Noh Moon, Chang Hee Lee, Ji Hyun Yoon, and Bong Sang Lee. "Bainitic Transformation Model in Low Alloy Carbon Steels Considering the Effect of Reaction Constant in JMA Equation." Materials Science Forum 475-479 (January 2005): 3157–60. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.3157.

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As a part of a study on modeling the microstructural evolution during the welding process, a prediction model of TTT diagram for bainite transformation was studied. This model consisted of a thermodynamic model for the bainite-start(Bs) temperature and a kinetic model for the bainite transformation. A kinetic model was empirically established for low alloy carbon steels, based on Johnson-Mehl-Avrami(JMA) equation. Reaction constants seemed not to have noticeable tendencies for temperatures and were averaged for each alloy. It was, however, found that the mean reaction constant significantly affected the reproducibility for the isothermal kinetics. Therefore, a calibration method to the kinetic parameter was proposed. From calibrations, rate constants were formulated as a function of alloying element and temperature. And TTT diagrams were calculated and compared with experiments.
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Domański, T., and A. Bokota. "Numerical Models of Hardening Phenomena of Tools Steel Base on the TTT and CCT Diagrams." Archives of Metallurgy and Materials 56, no. 2 (June 1, 2011): 325–44. http://dx.doi.org/10.2478/v10172-011-0036-6.

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Numerical Models of Hardening Phenomena of Tools Steel Base on the TTT and CCT DiagramsIn work the presented numerical models of tool steel hardening processes take into account thermal phenomena, phase transformations and mechanical phenomena. Numerical algorithm of thermal phenomena was based on the Finite Elements Methods in Galerkin formula of the heat transfer equations. In the model of phase transformations, in simulations heating process, isothermal or continuous heating (CHT) was applied, whereas in cooling process isothermal or continuous cooling (TTT, CCT) of the steel at issue. The phase fraction transformed (austenite) during heating and fractions of ferrite, pearlite or bainite are determined by Johnson-Mehl-Avrami formulas. The nescent fraction of martensite is determined by Koistinen and Marburger formula or modified Koistinen and Marburger formula. In the model of mechanical phenomena, apart from thermal, plastic and structural strain, also transformations plasticity was taken into account. The stress and strain fields are obtained using the solution of the Finite Elements Method of the equilibrium equation in rate form. The thermophysical constants occurring in constitutive relation depend on temperature and phase composite. For determination of plastic strain the Huber-Misses condition with isotropic strengthening was applied whereas for determination of transformation plasticity a modified Leblond model was used. In order to evaluate the quality and usefulness of the presented models a numerical analysis of temperature field, phase fraction, stress and strain associated hardening process of a fang lathe of cone shaped made of tool steel was carried out.
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Dissertations / Theses on the topic "Isothermic transformation diagrams"

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Finamor, Felipe Pereira 1986. "Efeito da adição de nióbio e molibdênio na deformação plástica e decomposição isotérmica da austenita em aços 0,7 %C." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265758.

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Orientador: Paulo Roberto Mei
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-28T12:29:26Z (GMT). No. of bitstreams: 1 Finamor_FelipePereira_M.pdf: 7096775 bytes, checksum: f9779c193bdb5089e6373c577ae23cc9 (MD5) Previous issue date: 2015
Resumo: O aumento da razão da carga transportada por eixo tem sido fundamental para redução dos custos de transporte, porém é exigido cada vez mais das interações roda-trilho. Neste aspecto para se garantir a segurança dos bens transportados e o menor desgaste da roda é necessário o desenvolvimento de novos aços com maior dureza, porém sem redução de ductilidade. Uma das estratégias é se adicionar aos mesmos microadições (< 0,5 % em massa) de nióbio ou vanádio, os quais, em solução sólida na austenita atrasam sua decomposição em produtos difusionais, elevando a resistência mecânica dos aços. Neste trabalho foram avaliados dois aços com 0,7 %C microligados ou não ao nióbio-molidbênio e produzidos pela MWL Brasil para a fabricação de rodas ferroviárias, segundo a classe D da AAR (Association of American Railroads). Foram realizados ensaios dilatométricos para o levantamento das curvas de transformação isotérmica e o estudo das curvas de escoamento à quente dos aços microligados e não microligados através dos ensaios de compressão à quente de único passe. A adição dos microligantes provocaram atrasos na cinética de transformação austenita/perlita na ordem de 4 vezes e um pequeno aumento da dureza dos produtos de reação no aço microligado ao nióbio e molibdênio para as transformações isotérmicas avaliadas por dilatometria e aumentaram numa razão de 1,3 a 1,4 as tensões de pico e em 1,5 a 3 as deformações de pico para todas as faixas de temperatura e deformação analisadas para o aço microligado
Abstract: The increase in cargo transported by axis has been a critical factor in reducing transportation costs, requiring more and more of the wheel-rail interaction. In this aspect to ensure the safety of transported goods and the a reduction in the wear of the railwheel is necessary to develop new steels with higher hardness without loosing ductility. One strategy is to add small amounts of alloy elements (<0.5 wt%) of niobium or vanadium which in solid solution in austenite retards the diffusional decomposition and raise the mechanical strength of the steels. The object of this study was to evaluate two steels with 0.7 % C microalloyed or not with niobium-molybdenum, which were produced by MWL Brasil for the production of railway wheels, according to Class D of AAR (Association of American Railroads) standards. Dilatometric tests were carried out to evaluate the isothermal transformation of microalloyed or not steels, and the flow curves were evaluated through microalloyed steels or not in a single hot compression tests. The addition of microalloying elements have delayed the kinetics of austenite transformation to pearlite in the order of 4 times and slightly increase the hardness of the reaction products in niobium and molybdenum microalloyed steel for isothermal transformations evaluated by dilatometry and increased in a ratio of 1.3 to 1.4 the peak stresses and 1.5 to 3 the peak strain for all ranges of temperature and strain analyzed for the microalloyed steel
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
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Kubota, Masahiro 1967. "The precipitation hardening response in A1-Mg(-Ag) alloys." Monash University, Dept. of Materials Engineering, 2001. http://arrow.monash.edu.au/hdl/1959.1/9204.

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Harish, Prakruth. "Understanding the Effect of Isothermal Heat Treatments on Microstructure of LMD-w Titanium Alloy (Ti-6242) - As-Built microstructure." Thesis, Högskolan Väst, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-15892.

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The most widely used titanium alloy in the hot sections of a jet engine is Ti-6Al-2Sn-4Zr-2Mo (Ti-6242) and with the technological advancements additive manufacturing (AM) of Ti-6242 is of great interest. Although, there is not much published related to additively manufactured Ti-6242. The project aimed to provide an experimental input for simulations of additively manufactured,laser metal deposited–wire (LMD-w) of Ti-6242. The main part of this project has been to experimentally study the effect of isothermal temperatures and holding times on the microstructural changes in as-built Ti-6242 on Ti-64 base-plate. The evaluation of micro-structural changes with isothermal temperature, holding time and cooling rates on Ti-6242 are quantified in terms of alpha laths, phase fraction by using MIPAR (image analysis software) and preliminary determine mechanical properties by performing hardness tests.The microstructures obtained through a process are highly dependent on the thermal history is it exposed to and the mechanical properties are determined by the microstructures present. In this thesis work the alpha lath thickness and the hardness of the material increases with increasing isothermal temperature. From the phase fractions obtained forthe heat treated samples an equilibrium phase diagram and a TTT diagram is plotted for as-built microstructure.
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Zahiri, Saden H. (Saden Heshmatollah) 1966. "Prediction of the processing window and austemperability for austempered ductile iron." Monash University, School of Physics and Materials Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/8408.

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Ikhlef, Aomar. "Transformations structurales de fontes à graphite sphéroïdal et influence spécifique du silicium : caractérisation par spectrométrie Mössbauer des diverses phases formées." Paris 11, 1985. http://www.theses.fr/1985PA112013.

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La transformation austénitique des fontes GS s’accompagne de la dissolution dans la phase γ formée, du carbone provenant des couches périphériques des nodules de graphite. L’analyse des transformations de l’austénite en refroidissement continue et par trempe isotherme a conduit au tracé des diagrammes TRC et TTT pour différentes teneurs en silicium. Le silicium exerce un effet déterminant sur la cinétique de la transformation bainitique en retardant la précipitation des carbures à partir de l’austénite. De ce fait, il favorise l’enrichissement en carbone d’une fraction de l’austénite et sa stabilisation transitoire. La décomposition de cette phase enrichie intervient, par la suite, par précipitation de silicocarbures complexes du type ԑ - (Fe, Si)₂₀C₉. Le revenu de la fonte GS s’opère en quatre stades nettement distincts précédés d’une étape de préprécipitation. La transformation de l’austénite résiduelle au cours du second stade se développe en deux étapes impliquant respectivement l’enrichissement en carbone d’une fraction de cette phase, puis sa décomposition par précipitation du carbure ԑ. Ce dernier carbure évolue, au cours du troisième stade, en un produit de transition de structure intermédiaire entre celles des carbures θ et χ
The austenitic transformation of S. G. Cast irons goes on with dissolution in the formed γ phase, some carbon coming from peripheric nodules of graphite. The analysis of the transformations of the austenite during the continuous cooling and during austempering resulted in CCT and TTT diagrams for different silicon contents. Silicon has an important effect on the kinetic bainite transformation: it delays the precipitation of the carbides from austenite. Therefore it favours the carbon enriching of a fraction of the austenite, and its temporary stabilization. The decomposition of this enriched phase takes place then, by precipitation of complex silicocarbides of type ԑ - (Fe, Si)₂₀C₉. The tempering of S. G. Cast iron occurs in four distinct stages, preceded by an aging step. The transformation of the retained austenite during the second stage is separated into two steps, involving respectively the carbon enriching of a fraction of this phase, and its decomposition by precipitation of ԑ carbide. During the third stage, this ԑ carbide transforms into a transition carbide having an intermediate structure between θ and χ carbides
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Kovarik, Libor. "Microstructural study and modeling of metastable phases and their effect on strenghthening [sic] in Al-Mg-Cu-Si alloying system." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1149006665.

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Hamou, Ahmed. "Relaxation et cristallisation d'alliages chalcogènes vitreux riches en sélenium : influence de la coordination de l'élément d'addition." Rouen, 1993. http://www.theses.fr/1993ROUES001.

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Le but du travail présenté dans cette thèse est de chercher à partir de matériaux modèles, des grandeurs ou des méthodes pouvant caractériser la structure d'un verre. Dans une première partie, nous justifierons le choix des alliages étudiés (Se, Se-As, Se-Bi et Se-Ge). Puis nous présenterons leurs structures cristallines et vitreuses, enfin nous donnerons un bref aperçu des méthodes expérimentales utilisées pour la fabrication et le contrôle des échantillons. La deuxième partie est consacrée aux résultats expérimentaux. Par les études de la relaxation et la cristallisation des alliages étudiés, nous avons mis en évidence l'existence d'énergies d'activation caractéristiques du verre. Ces énergies sont liées au nombre moyen de coordination (M) de l'alliage. Nous avons alors retrouvé les valeurs du nombre de coordination (NCO) d'atomes (Te et Bi) dont la nature covalente de la liaison ne semble pas être évidente. Par les études de la relaxation et de la recristallisation du Se-As et du Se-Ge, nous avons mis en évidence des valeurs critiques de la composition non prévues par les diagrammes de phase de ces alliages. Citons entre autres la valeur de M égale à 2. 08 au-delà de laquelle la cristallisation disparaît. Pour les matériaux préparés sous forme de couche mince, nous avons étudié l'influence sur la cristallisation des conditions de préparation et déterminé les paramètres de cette cristallisation
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Books on the topic "Isothermic transformation diagrams"

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Atlas of time-temperature diagrams for nonferrous alloys. [United States]: ASM International, 1991.

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F, Vander Voort George, ed. Atlas of time-temperature diagrams for irons and steels. [United States]: ASM International, 1991.

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Book chapters on the topic "Isothermic transformation diagrams"

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Dudás, Zoltán. "Comparing of the Processes of the Isothermal Phase Transformations of the Material Type 50 CrV 4 Using Different TTT Diagrams and Applying FEM Based Phase Elements." In Materials Science, Testing and Informatics II, 321–28. Stafa: Trans Tech Publications Ltd., 2005. http://dx.doi.org/10.4028/0-87849-957-1.321.

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Kessler, Olaf, Benjamin Milkereit, and Christoph Schick. "Quench Sensitivity and Continuous Cooling Precipitation Diagrams." In Encyclopedia of Aluminum and Its Alloys. Boca Raton: CRC Press, 2019. http://dx.doi.org/10.1201/9781351045636-140000288.

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The application properties of metallic materials are frequently adjusted by heat treatments utilizing controlled microstructural changes—i.e., solid–solid phase transformations like nondiffusional martensitic transformation or diffusional secondary phase precipitation and/or dissolution. For technical application, knowledge about the characteristic temperatures and times but moreover about their time dependence (kinetics) is required. As the relevant solid–solid phase transformations all show a heat effect (e.g., precipitation → exothermic; dissolution → endothermic), one outstanding measurement technique to follow these phase transformations is calorimetry, particularly differential scanning calorimetry (DSC). Appropriate combinations of DSC methods and devices to cover nine orders of magnitude in heating and cooling rates (10−4–105 K/s) will be introduced, using dissolution and precipitation reactions in aluminum alloys as examples. Basically, these techniques allow one to record time–temperature transformation (or precipitation/dissolution) diagrams for various materials during heating, isothermal annealing, and even during continuous cooling, making DSC a very powerful tool for the investigation of solid–solid phase transformations. Nowadays, physically based models verified with DSC results moreover allow one to predict precipitation volume fractions and solute mass fractions.
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Conference papers on the topic "Isothermic transformation diagrams"

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Konh, Bardia, Mohammad Honarvar, and Parsaoran Hutapea. "Application of SMA Wire for an Active Steerable Cannula." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3142.

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In this article we present the feasibility of using the shape memory alloy (SMA) wires, namely Nitinol, as an actuator for a steerable surgical cannula. A 3D finite element (FE) model of the actuated steerable cannula was then developed in ANSYS to show deflection of the surgical cannula under the actuation force. The behavior of SMAs was simulated by defining the isothermal stress-strain curves using the multi-elasticity capability of ANSYS. The transformation temperatures of the Nitinol wire at different levels of stress were gathered to form the transformation diagram. Using the one-dimensional Brinson model, the isothermal stress-strain response of the wire was obtained. The thermomechanical characteristics of SMAs were also studied completely by a series of experiments performed on the wires. Birth and death method was used in the solution procedure to have the prestrain condition on Nitinol wire prior to the actuation step. A prototype of the actuated steerable cannula was also developed to validate the numerical simulation. Finally a study was done on design parameters affecting the deflection such as Young’s modulus of cannula, SMA diameter and its offset from the neutral axis of the cannula which can be useful in design optimization.
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Lasne, Patrice, Mickael Barbelet, Olivier Jaouen, Frederic Costes, Ihab Ragai, and Harry Tempelman. "Simulation of the Heat Treatment of an Automotive Cast Part." In ASME 2010 International Manufacturing Science and Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/msec2010-34152.

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In this paper, simulation of the casting and heat treatment processes of front spindle of a rigid dump truck are presented. The objectives are to present how the different operations can be simulated in order to predict the local phases in the different areas of the part. To reach these objectives, two software packages are used in sequenced. The first one, Thercast, is used to simulate the casting operation. The second one, Forge, is applied to the water-quenching simulation. The general formulations used are shortly presented in this paper. The aim of casting simulation is to compute the metal behavior from the liquid state at the pouring stage to the solid state during cooling into the mold. Filling and cooling phases simulations, taking into account the air gap, ensure that no internal defects like shrinkage, porosity, micro porosity or hot tearing are taking place into the part. Forge software allows the water quenching stage simulation. A model is used to deduct the IT diagram (Isothermal Transformation diagram) from the material composition. The initial grain size influences the transformation kinetics. Another main phenomenon is the efficiency of the cooling bath. The results of the simulation (phase distribution, distortion, residual stresses) strongly depend on these input conditions. Thus, the effect of input data variations on final results must be studied. The modeling approach is validated by comparisons with micrographic observations. Another solution to determine the reliability of the models is to observe the local properties in the quenched part. The prediction of the local micro hardness can be used to evaluate the accuracy of the quenching models.
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