基于CAFE模拟双辊连铸纯铝凝固微观组织

鉴于双辊薄带连铸等轴晶区半固态铸轧组织对产品性能的重要性,基于热传输、流动传输、溶质传输等基本传输过程以及晶粒生长物理过程,建立了双辊连续铸轧纯铝凝固过程的宏观温度场、浓度场、微观组织及枝晶形貌演化的三维数学模型.采用CA-FE法对双辊连续铸轧纯铝在水冷钢辊连续铸轧中的凝固过程进行了模拟,采用光学显微镜研究了铸轧工艺参数对凝固组织的影响.数值模拟结果表明,所建立的数学模型能够合理描述晶粒沿任意角度生长的过程,温度场、溶质场和微观组织形貌的模拟计算结果合理.模拟结果与实验结果基本吻合,检验了模型的正确性.

Microstructures in solidification simulation of twin-roll continuous casting pure aluminum with CAFE

The width of columnar grain zone in as cast strips is mainly determined by the length of columnar grains at nip point.Coupling temperature field,concentration field and micro growth,based on the basic transfer process,including heat transfer,flow transfer and solute transfer,and the physics of growth process of crystal grains,the mathematical models for the 3D simulation of microstructure and free dendrite growth of twin-roll continuous casting pure aluminum thin strip were developed.The simulation of the solidification process of pure aluminum in water-cooled steel mould of twin-roll continuous casting was presented by CA-FE method.The influence of continuous casting process parameters on the solidification microstructure were researched by optical microscope.The results show that the grain growth in random preferential growth directions can be described by the model reasonably,and the calculation results fit the experimental ones well.