低碳钢热变形过程中动态相变的同步耦合模拟

项目名称： 低碳钢热变形过程中动态相变的同步耦合模拟

项目编号： No.50871109

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 李殿中

作者单位： 中国科学院金属研究所

项目金额： 31万元

中文摘要： 建立微米亚微米级晶粒尺度的介观计算模型，发展集变形与相变于一体的新算法，模拟低碳钢在热变形过程中的动态相变，定量研究其形核长大机理和特有规律。建立奥氏体/铁素体双相组织的晶体塑性有限元模型，以有限元和元胞自动机方法为基础，开发数据双向传输接口与大尺寸模拟体系的并行算法，首次建立变形和相变同时进行的同步耦合介观计算模型。结合热模拟实验，计算不同温度、应变和应变速率条件下大尺寸Gleeble 试样的动态相变，揭示动态相变的形核长大规律以及与已有的先变形后相变过程的差异。以期解决常规计算模型无法进行同步耦合计算和传统实验手段无法实施动态观测而影响动态相变结果分析的问题。本项研究不仅有助于加深理解动态相变的复杂性，而且对促进整个变形过程中组织演变的系统研究、优化形变与相变工艺、提高低碳钢性能都具有重要意义。

中文关键词： 同步耦合；动态相变；元胞自动机；晶体塑性有限元

英文摘要： The dynamic phase transformation during the hot deformation of low carbon steels will be investigated by building the micron- or submicron-level computational model at grain scale. the new algorithm combined both deformation model and transformation model is used to study the mechanism of dynamic transformation nucleation and growth. the crystal plasticity finite element model (CPFEM) of austenite/ferrite dual-phase microstructure will be built. Based on the CPFEM and cellular automaton, the synchronous integration model can be established by developing the Two-way data communication interface and the parallel algorithm of large-scale simulation system. Then the simulation of dynamic transformation at different deformation conditions will be impleted using this new model. Considering the Gleeble experiments, the mechanism of nucleation and growth of dynamic transformation and the difference with the static deformed austenite decomposition will be studied. This new model will solve the problem that the traditional models can not be used for the synchronous integration simulation. The present study will not only be useful for understanding the complexity of dynamic transformation, and also be helpful for improving the research of microstructure evolution and optimizing the deformation-transformation technology.

英文关键词： synchronous integration; dynamic transformation; cellular automaton; crystal plasticity finite element