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TEM observation of precipitation phase produced during tempering of steel AerMet100 and first principles calculations of phase evolution

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Rare Metals 2007年第S1期26卷 326-330页

作者： WANG Xiangrong,yan mufu,and meng qingchang School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The microstructure evolution law and the structure of precipitates produced during the tempering of steel AerMet100 based on TEM observation and the calibration of diffraction spot were *** electronic structure and the stability of the MoxCr2-xC phase were calculated using the plane-wave pseudo-potential method on basis of density functional *** observations show that the precipitation phases Fe3C and Fe2-xCx(x=0.05～0.14) between martensite lath are produced at 425 and 480 ℃,*** increase of tempering temperature or time can lead to the redissolution of both phases Fe3C and Fe2-xCx,and also lead to the precipitation of the phase Cr2C in martensite *** calculation results of formation energies and the density of state(DOS) demonstrate that in point of MoxCr2-xC structures formed during tempering,the early precipitation phase is Cr2C and finally later evolves into Mo2C phase with diffusing of incorporation of Mo atom into the Cr2C crystal cell,lattice,which can results in a energy decreases of the structure MoxCr2-xC phase with the increase of x.

关键词： steel AerMet100 tempering phase evolution formation energies DOS

3Cr13钢530℃和560℃等离子体渗氮层表征

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金属热处理 2018年第8期43卷 193-197页

作者：由园闫纪红闫牧夫李莉孙熙罡王超会哈尔滨工业大学机电工程学院黑龙江哈尔滨150001 齐齐哈尔大学材料科学与工程学院黑龙江齐齐哈尔161006 哈尔滨工业大学材料科学与工程学院金属精密热加工国家级重点实验室黑龙江哈尔滨150001

在530℃和560℃对3Cr13钢进行了4、8和16 h离子渗氮,利用9XB-PC金相显微镜、D8-FOCUSX射线衍射、HV-1000IS显微硬度计、CPA-225D电子天平和CS310电化学工作站,对改性层的截面显微组织、表面层相组成、硬度、质量增加和耐腐蚀性能进行了... 详细信息

在530℃和560℃对3Cr13钢进行了4、8和16 h离子渗氮,利用9XB-PC金相显微镜、D8-FOCUSX射线衍射、HV-1000IS显微硬度计、CPA-225D电子天平和CS310电化学工作站,对改性层的截面显微组织、表面层相组成、硬度、质量增加和耐腐蚀性能进行了测试。试验结果表明,3Cr13钢530℃渗氮4、8和16 h后致密层厚度分别为96、116、149μm,560℃渗氮4、8和16 h后致密层厚度分别为105、164、172μm,渗氮致密层的厚度随渗氮时间和温度的增加而增加;3Cr13钢530℃渗氮4、8和16 h后致密层截面平均硬度分别为1062.8、1084.0、1155.7 HV0.05,560℃渗氮4、8和16 h后,致密层截面平均硬度分别为1126.4、924.3、726.0 HV0.05。3Cr13钢530℃渗氮后改性层耐蚀性提高,4 h改性层耐蚀性最好,16 h次之,8 h改性层的耐蚀性接近未渗氮试样;与未渗氮试样相比,3Cr13钢560℃渗氮4 h后改性层的耐蚀性提高,8 h和16 h后改性层的耐蚀性降低。

关键词： 3Cr13钢等离子体渗氮显微组织显微硬度耐蚀性

Numerical Simulation of Carbon Concentration Profiles in Case Layer of Steel 20 RE-Carburized in Multipurpose Furnace with Drip-Feed Atmosphere

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Journal of Shanghai Jiaotong university(Science) 2000年第1期5卷 310-313页

作者： mufu yan, jihong yan, Zhiru Liu 1.School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R.China 2.Department of Automation, Tsinghua University, Beijing 100084, P. R. China

The carburizing process has been successfully carried out in multipurpose furnace employing the drip-feed atmosphere with the addition of rare earth (RE). The carbon transfer coefficients (BRE) and mean diffusion coefficient (DRE) were calculated respectively based on the kinetics of the specimens weigh gain per unit area and the carburized layer growth. The results show that the BRE and DRE are all increased on basis of the incorporation of rare earth. In addition, the mathematical models of the carbon concentration profile under different carburizing conditions and the carbon diffusion coefficient DSRE (at x=0 for carburizing time t>0) have been deduced using the profile simulation method. Computer simulation results show that the simulated curves coincide quite well with the experimental data.

关键词： Multipurpose Furnace RE-Carburizing, Carbon Concentration Computer Simulation

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2Cr13钢440℃等离子体渗氮

金属热处理 2017年第5期42卷 172-175页

作者：由园闫纪红闫牧夫景立伟陶玉斌王超会孙皓哈尔滨工业大学机电工程学院黑龙江哈尔滨150001 齐齐哈尔大学材料科学与工程学院黑龙江齐齐哈尔161006 哈尔滨工业大学金属精密热加工国家级重点实验室材料科学与工程学院黑龙江哈尔滨150001

对2Cr13钢进行了440℃等离子体渗氮,利用金相显微镜(OM)、分析天平、X射线衍射仪(XRD)、显微硬度计和电化学工作站等仪器,对渗氮层的显微结构、增重、相组成、硬度分布和耐腐蚀性能进行了测试。结果表明:2Cr13钢在440℃氮氢比为1∶3条... 详细信息

对2Cr13钢进行了440℃等离子体渗氮,利用金相显微镜(OM)、分析天平、X射线衍射仪(XRD)、显微硬度计和电化学工作站等仪器,对渗氮层的显微结构、增重、相组成、硬度分布和耐腐蚀性能进行了测试。结果表明:2Cr13钢在440℃氮氢比为1∶3条件下渗氮4 h、8 h和16 h后,渗氮层厚度逐渐增加,最厚为58.9μm;渗氮层质量随时间的增加而增大,增重最高为1.57×10^(-3)g/cm^2;渗氮层显微硬度显著增高,最大为1170.0 HV0.05;渗氮层表面由ε-Fe_3N和γ'-Fe_4N组成;渗氮层表面极化曲线出现钝化区,腐蚀速率显著下降,耐蚀性显著提高。

关键词： 2Cr13钢等离子体渗氮显微组织显微硬度耐蚀性

Mathematical Models and Computer Simulation of Nitrogen Concentration Profiles in Pulse Ion Nitrided Layers

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Journal of Shanghai Jiaotong university(Science) 2000年第1期5卷 294-297页

作者： mufu yan, jihong yan, Lifang Xia, Yong Sun, Tom Bell 1.School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China 2.Department of Automation, Tsinghua University, Beijing 100084, P. R. China 3.School of Meta

The nitrogen concentration profiles in surface layers and surface phase structures were accurately measured respectively using the glow discharge spectrometry and X-ray Diffractometer after the specimens had been pulse ion nitrided at 500℃ for 0.2-8h The results show that the compound layer growth, which is different from that of conventional DC nitriding, conforms to parabolic law At the same time the surface nitrogen concentration change little with increasing the nitriding time, at least it is so when the treating time is longer than 0.2h In addition, the mathematical models of nitrogen concentration profiles in ε -Fe2~3N,γ-Fe4N and α -Fe phases have been established. Using them the nitrogen concentration profiles in nitrided layers were simulated. Results show that the simulated curves coincide quite well with the experimental data.

关键词： Pulse Ion Nitriding Nitrogen Concentration Profile Computer Simulation

3Cr13钢450℃不同气氛等离子体渗氮层表征

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金属热处理 2021年第11期46卷 120-125页

作者：李芮由园闫牧夫闫纪红陈宏涛王超会刘东静洪霖齐齐哈尔大学材料科学与工程学院黑龙江齐齐哈尔161006 哈尔滨工业大学材料科学与工程学院金属精密热加工国家级重点实验室黑龙江哈尔滨150001 哈尔滨工业大学机电工程学院黑龙江哈尔滨150001 哈尔滨理工大学材料科学与工程学院黑龙江哈尔滨150040

对3Cr13钢在450℃氨气和氨氮混合气氛中分别渗氮4、8和12 h后的渗氮层进行了对比。利用光学显微镜、显微硬度计、X射线衍射仪、电化学工作站对渗氮层截面显微组织、显微硬度、相组成以及耐蚀性进行了表征。氨气渗氮层由化合物层和白亮... 详细信息

对3Cr13钢在450℃氨气和氨氮混合气氛中分别渗氮4、8和12 h后的渗氮层进行了对比。利用光学显微镜、显微硬度计、X射线衍射仪、电化学工作站对渗氮层截面显微组织、显微硬度、相组成以及耐蚀性进行了表征。氨气渗氮层由化合物层和白亮层组成,而氨气和氮气混合气氛渗氮层中没有出现白亮层。氨气渗氮12 h后,渗氮层的表面硬度为1050.0 HV0.05;表面化合物层主要相为ε-Fe_(2-3)N,次要相为γ'-Fe_(4)N,出现了少量的CrN,白亮层相组成为γ'-Fe_(4)N;渗氮后极化曲线钝化区变宽,自腐蚀电流密度减小,耐蚀性提高。氨氮混合气氛渗氮12 h后,渗层的表面硬度为998.0 HV0.05;气氛中N浓度升高,渗氮8 h后CrN含量增加,次要相由氨气渗氮8 h的γ'-Fe_(4)N变为CrN;随着渗氮时间延长至12 h,渗层的自腐蚀电流密度降低,钝化区略有变宽,耐蚀性略有提高。

关键词： 3Cr13钢等离子体渗氮气氛显微组织性能