基于多场耦合的Cr12MoV钢调质过程数值模拟

发布时间：2018-05-07 18:17

本文选题：调质 + 数值模拟　；参考：《天津职业技术师范大学》2015年硕士论文

【摘要】：模具是工业发展的基础，是工业化实现产品批量生产和新产品研发不可或缺的成型工具。Cr12MoV钢是国内外应用最广泛的冷作模具钢之一，在现代工业应用中占有十分重要的地位。Cr12MoV钢的强度、硬度较高，耐磨性较好，其韧性较差，因而对热处理工艺和热加工工艺要求较高，若处理工艺不当，很容易造成模具的过早失效。传统的热处理工艺开发多采用经验和半经验的方法，不仅耗费大量的人力、财力，而且难以精确地控制质量。随着计算机技术的发展和新的模拟技术的出现，热处理过程的数值模拟也随之成为一个倍受关注的研究领域。本文以Cr12MoV钢为研究对象，基于理论、模拟和实验相结合的技术路线，将相变-热-力多场耦合理论应用到Cr12MoV钢调质过程中。采用COSMAP有限元分析软件对Cr12MoV钢调质过程的温度场、组织场、应力场进行了研究。研究Cr12MoV钢调质过程的温度场。同时考虑变形热、相变潜热以及非线性参数的影响，对Cr12MoV钢热处理过程温度的变化进行了预测。通过采集系统得到试样外表面和中心处的冷却曲线来验证热处理过程中温度的变化情况。研究Cr12MoV钢调质过程的组织场。分别预测了淬火和回火阶段组织和硬度的变化和分布情况。通过试验验证了组织和硬度的模拟结果。研究Cr12MoV钢调质过程的应力场。分别对Cr12MoV钢热处理后的应力和变形进行了预测，，得出了Cr12MoV钢淬火和回火阶段残余应力的变化规律以及不同热处理条件下的变形量大小及分布。通过影像测量仪验证了数值分析的变形量。基于以上结果，最终建立了可优化Cr12MoV钢热处理工艺参数的有限元模型。
[Abstract]:Mould is the foundation of industrial development, and it is one of the most widely used cold-working die steels at home and abroad, which is an indispensable forming tool for industrial mass production and new product research and development. The strength, hardness, wear resistance and toughness of Cr12MoV steel are very important in modern industrial application. It is easy to cause premature failure of the mould. The traditional heat treatment process development mostly adopts the experience and the half experience method, which not only consumes a lot of manpower and financial resources, but also is difficult to control the quality accurately. With the development of computer technology and the emergence of new simulation technology, numerical simulation of heat treatment process has become a research field. Taking Cr12MoV steel as the research object, based on the technical route of combining theory, simulation and experiment, the phase-change thermal-force multi-field coupling theory is applied to the quenching and tempering process of Cr12MoV steel. The temperature field, microstructure field and stress field of Cr12MoV steel during quenching and tempering were studied by COSMAP finite element analysis software. The temperature field of Cr12MoV steel during quenching and tempering is studied. Considering the influence of deformation heat, latent heat of transformation and nonlinear parameters, the variation of temperature during heat treatment of Cr12MoV steel was predicted. The cooling curves at the outer surface and the center of the sample were obtained by the acquisition system to verify the change of temperature during heat treatment. The microstructure field of Cr12MoV steel during quenching and tempering was studied. The change and distribution of microstructure and hardness in quenching and tempering stages were predicted respectively. The simulation results of microstructure and hardness are verified by experiments. The stress field of Cr12MoV steel during quenching and tempering is studied. The stress and deformation of Cr12MoV steel after heat treatment were predicted, and the variation law of residual stress in quenching and tempering of Cr12MoV steel was obtained, as well as the magnitude and distribution of deformation under different heat treatment conditions. The deformation of the numerical analysis is verified by the image measuring instrument. Based on the above results, a finite element model for optimizing the heat treatment process parameters of Cr12MoV steel is established.
【学位授予单位】：天津职业技术师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG142.1

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