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The Developments and Application of Computer Simulation in Heat Treatment Process Based on Metallo-Thermo-Mechanical Theory

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材料科学与工程学报 2000年第Z2期20卷 921-927页

作者： dong-ying ju Department of Mechanical Engineering Saitama Institute of Technology Fusaiji 1690Okabe Saitama 369-02

The aim of this paper is to introduce the application and future of computer simulation in heat treatment process, as an important method in manufacturing of material. Here, developments of the finite element based on a code 'HEARTS will are presented by using some experiments to be applied simulation of general quenching, quenching-tempering and quenching with carbonization or induction. The code 'HEARTS' for 3-D simulation of heat treatment process based on a metallo-thermo-mechanical theory is presented. Coupled equations of heat conduction, inelastic stresses and kinetics of phase transformations are derived as well as the diffusion equation during carbonization, followed by finite element formulation. The program is available for 2-D and 3-D simulation of various heat treatment processes, such as quenching,tempering and so on. The system is used in the CAE environment of some pre-and post-processors over 'Ⅰ-DEAS ', 'PATRAN' or 'FEMAP'. Some examples of simulated results of carbonized quenching processes for cylindrical rod, ring and gear wheel are also presented.

关键词： Treatment Process heat treatment treatment process finite element application and future phase transformations computer simulation diffusion equation heat conduction cylindrical rod used in

Simulation of critical cooling rate and process conditions for metallic glasses in vertical type twin-roll casting

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Transactions of Nonferrous Metals Society of China 2017年第11期27卷 2406-2414页

作者： Zhi-pu PEI dong-ying ju Xue LI Graduate School of Saitama Institute of Technology Fusaiji 1690 Fukaya Saitama 369-0293 Japan Department of Material Science and Engineering Saitama Institute of TechnologyFusaiji 1690 Fukaya Saitama 369-0293 Japan School of Materials and Metallurgy University of Science and Technology Liaoning Anshan 114051 China

Critical cooling rates for producing metallic glasses were evaluated based on a calculated continuous cooling transformation(CCT)*** distributions of the melt in molten pool in the vertical type twin-roll casting(VTRC)process of metallic glasses were simulated,and cooling rates under different casting conditions were calculated with the simulated *** comparing the results obtained by CCT diagrams and simulation,the possibility of producing metallic glasses by the VTRC method and influences of casting conditions on cooling rate were *** results reveal that cooling rate with3or4orders of magnitude by the VTRC process can be attained in producing Mg-based metallic glasses,which is faster than the critical cooling rate calculated by the CCT *** side pouring mode can improve the temperature distributions of casting *** process has a good ability in continuous casting metallic glassy thin strips.

关键词： metallic glass critical cooling rate twin-roll casting simulation

Heat Treatment Simulation for Low Pressure Hyper Carburizing Process

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Journal of Mechanics Engineering and Automation 2019年第1期9卷 33-39页

作者： Tsuyoshi Sugimoto dong-ying ju Nissan Motor Co. Ltd.AtsugiKanagawaJapan Saitama Institute of Technology FukayaSaitamaJapan

Carburizing heat treatment is well used to increase the strength of gears and automobile drivetrain *** very high contact fatigue strength is required,hyper carburizing or carbonitriding is well used to improve the surface hardness and tempering softening *** saturate carburizing as called hyper carburizing can be used in a conventional ordinary carburizing furnace and investment of new gas supply equipment is unnecessary,while there are problems such as controlling precipitation of cementite and securing hardenability of the surface,***,problems such as secondary precipitation to control the material micro structure,its quality prediction method becomes *** recent years the low pressure carburizing method has been widely used and the possibility of making hyper carburizing in low cost has been ***,when hyper carburizing is performed by low pressure carburizng,reticulated cementite occurs at the edge of the part,there is a problem such as local increase of carbon concentration distribution and *** this study,we tried to formulate precipitation when super carburizing was performed on steel parts using a low pressure carburizing furnace,formulated the surface hardness distribution,and tried to calculate the hardness and cementite precipitation size *** method is used to obtain the physical property values,graphite of an intermediate product was precipitated from the low pressure carburizing atmosphere on the surface layer,and it was assumed that carburization occurred *** supersaturated carbon precipitates as cementite,the growth amount of the precipitate is *** deposition rate was estimated by comparing the actual measurement with the calculated *** hardness is determined by the sum of the hardness of the precipitate and the hardness of the parent phase part,the hardness distribution was *** a result,the hardness distribution at the time of high c

关键词： Heat treatment simulation low pressure carburizing hyper carburizing cementite precipitation

Modeling and Simulation of Iron-Carbon Phase Transformation During Tempering of Steel

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稀有金属材料与工程 2012年第S1期41卷 6-12页

作者： dong-ying ju1,Xiao-hu Deng 2 1Department of Mechanical Engineering,Saitama Institute of Technology,Saitama,Japan 2 Advanced Science Research Laboratory,Saitama Institute of Technology,Saitama,Japan Saitama Inst Technol Dept Mech Engn Saitama Japan Saitama Inst Technol Adv Sci Res Lab Saitama Japan

Tempering is final process used in heat treatment of steel *** is important to improve the toughness and ductility of the quenched steel without a great loss of the hardness and ***,the traditional tempering process is hard to satisfy requirements of combination mechanical properties with low cost.A quantitative model is developed to simulate the micro-structural evolution during tempering process of carbon steel by modifying the previous ju and Inoue's *** model takes into account tempering parameters,carbon content and morphology for iron-carbon *** of carbon atoms,precipitation of transition carbides(ε-carbide),decomposition of retained austenite and precipitation of cementite can be predicted *** precipitation of carbides is modeled by considering the competitive precipitations ofε-carbide and *** kinetics of decomposition of retained austenite into ferrite and cementite is depicted by the modified Avrami *** validate the model,it is applied to simulate the tempering process of the as-quenched plain carbon *** volume fractions of iron-carbon phase are calculated at different tempering temperature and *** is indicated that tempering time has greater effect on the volume fraction of carbides at high temperature *** calculated results are reasonable consistent with the theoretical descriptions.

关键词： tempering phase transformation kinetics transition carbide cementite

Hot tensile deformation behavior and globularization mechanism of bimodal microstructured Ti-6Al-2Zr-1Mo-1V alloy

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Transactions of Nonferrous Metals Society of China 2018年第12期28卷 2449-2459页

作者： Hui-jun ZHAO Bao-yu WANG dong-ying ju Guo-jin CHEN School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou 310018China School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

The hot deformation behavior,microstructure evolution and fracture characteristics of bimodal microstructured Ti-6Al-2Zr-1Mo-1V alloy were investigated by isothermal tensile *** reveal that flow softening is caused by dynamic globularization of the bimodal microstructure,which also results in a relatively high stress exponent and thermal activation *** corresponding SEM,EBSD and TEM observations indicate that the dynamic globularization at750and800℃is accomplished by the formation ofα/αsub-grain boundary and penetration of theβ***,dynamic recrystallization(DRX)is the main globularization mechanism at850℃,which was proved by the generation of fine grains with a necklace-like character due to the transformation of low-angle boundaries(LABs)into high-angle boundaries(HABs).With an increase in the deformation temperature or a decrease in the strain rate,the fracture mechanism changes from microvoid coalescence to intergranular fracture.

关键词： titanium alloy bimodal microstructure deformation behavior globularization mechanism fracture morphology

Modification of ricin and its hepatotoxicity and activity against hepatocellular cancer in mice

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World Journal of Gastroenterology 1998年第4期4卷 35-38页

作者： WANG WenXue, dong juying, ZHOU SiYuan, LI WenLi and ZHAO yingKeywords ricin/chemistry ricin/toxicity liver/drug effects liver neoplasms carcinoma, hepatocellular glutathione transferase

AIM To observe the effects of ricin (RT) with and without chemical modification on both hepatotoxicity of mice and activity against hepatocellular cancer (HCC), and evaluate the possibility to improve RT anticancer activity via chemical *** RT was modified with N-succinimidyl3-(2-pyridyldithio) propionate (SPDP), a heterobifunctional cross-linker, and SPDP derivative of RT (PDP-R) was obtained. The serum glutathione-s-transferase (SGST) activity, as an index of liver damage, was determined in mice intoxicated with RT and PDP-R, at various doses and time. The tissue damage of HCC in the nude mice ip injected with PDP-R was compared with that with RT at the same dose by immunohistochemical method, the relative content of both RT and PDP-R in the HCC tissues was measured by computerized *** The SGST activities increased with doses or/and time intoxicated with both RT and PDP-R, and the increase in the value of RT group was more significant than that in the PDP-R group; the SGST activity of RT group was 2.8-fold (P＜0.01) of PDP-R group at a dose of 12.5μg/kg for 42h, showing the much lower toxicity of R-PDP than that of RT. Under an optical microscope, hemolysis and necrosis of massive cells in the HCC tissues of PDP-R group were observed and the ratio of necrosis mounted to 90.5% while the corresponding value of RT group only to 62.5%. With computerized image-analysis, the average relative content of RT and PDP-R in the HCC tissues, represented as greyness, was 140.06±3.43 and 169.10±2.74, respectively. There was significant difference between the two (P＜0.05), indicating the higher content of PDP-R in the HCC tissue than that of *** The hepatotoxicity of PDP-R to mice may be reduced by chemical modification with SPDP, but both the affinity of PDP-R to the HCC tissues and ability to kill it may be stronger than that of RT. So this might be a valuable attempt to improve the anticancer activity of RT.

关键词： ricin Modification

Effect of annealing temperature on joints of diffusion bonded Mg/Al alloys

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Transactions of Nonferrous Metals Society of China 2018年第2期28卷 251-258页

作者：丁云龙王建刚赵明巨东英 Department of Material Science and Engineering Saitama Institute of Technology 河北科技大学河北省材料近净成形技术重点实验室石家庄050018 辽宁科技大学材料科学与工程系鞍山114051

To study the effect of annealing temperature on the joints between magnesium and aluminum alloys, and improve the properties of bonding layers, composite plates of magnesium alloy（AZ31 B） and aluminum alloy（6061） were welded using the vacuum diffusion bonding method. The composite specimens were continuously annealed in an electrical furnace under the protection of argon gas. The microstructures were then observed using scanning electron microscopy. X-ray diffractometry was used to investigate the residual stresses in the specimens. The elemental distribution was analyzed with an electron probe micro analyzer. The tensile strength and hardness were also measured. Results show that the diffusion layers become wide as the heat treatment temperature increases, and the residual stress of the specimen is at a minimum and tensile strength is the largest when being annealed at 250 ℃. Therefore, 250 ℃ is the most appropriate annealing temperature.

关键词： annealing temperature diffusion bonding diffusion layer residual stress tensile strength

Development and Application of Computer Simulation in Heat Treatment Process

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Development and Application of Computer Simulation in Heat T...

蓖麻毒素对肝癌细胞核转录因子NF-κB的激活作用

2005年全国计算材料、模拟与图像分析学术会议

作者： dong-ying ju Department of Material Science and Engineering, Saitama Institute of Technology, Fusaiji 1690, Okabe Saitama 369-02, Japan

INTRODUCTION In the processes incorporating phase transformation, such as quenching, welding, casting and so on, the mechanical properties of manufactured matterial are necessary to be depended on coupled analysis of incorporating with temperature field, stresses fields and since the structural change due to phase transformation. The coupling analysis based on the metallo-thermo-mechanical theory is proposed by some studies[1-7]. The theory shows an important relation involving of the three fields

关键词： Development and Application of Computer Simulation in Heat Treatment Process

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癌症 2000年第12期19卷 1109-1111页

作者：董巨莹彭宣宪药立波厦门大学生物系肿瘤细胞工程教育部重点实验室福建厦门361005 第四军医大学生化与分子生物学教研室陕西西安710032

目的：探讨蓖麻毒素细胞毒性作用的分子机理。方法：采用免疫细胞化学和 Western blot等方法观察蓖麻毒素作用于人肝癌细胞后，引起核转录因子 NFκ B的变化。结果： 100 pmol/L的蓖麻毒素处理细胞后，随着时间的延长（ 30 min、 1 h... 详细信息

目的：探讨蓖麻毒素细胞毒性作用的分子机理。方法：采用免疫细胞化学和 Western blot等方法观察蓖麻毒素作用于人肝癌细胞后，引起核转录因子 NFκ B的变化。结果： 100 pmol/L的蓖麻毒素处理细胞后，随着时间的延长（ 30 min、 1 h和 2 h）， NFκ B由胞浆逐渐向核内转移， 2 h后胞浆和胞核的着色均变浅，表明 NFκ B的活性略有减弱；随着蓖麻毒素浓度的增大，核内棕色颗粒也有加深的趋势。结论：本结果表明蓖麻毒素通过其糖配基与肝癌细胞相互作用后，能启动核转录因子 NFκ B的表达。 NFκ B激活在其抗癌作用中起着重要作用。

关键词：蓖麻毒素肝癌细胞 NF-κB 激活作用