论文部分内容阅读
采用CellularAutomaton微观模型 ,对压铸镁合金的三维微观组织演变进行了模拟。在模拟过程中 ,采用连续形核模型处理液态金属的异质形核现象 ,通过正态分布函数描述形核质点密度随温度的分布关系 ,在给定过冷度时对分布函数积分可得到该时刻的形核密度 ,晶粒生长模型则考虑了枝晶尖端生长动力学和择优生长方向 <10 10 >,也考虑了温度场的影响 ,并完成了宏观温度场和微观计算的耦合。最后通过压铸镁合金标准拉伸试棒金相试验 ,对模拟结果进行了验证 ,试验结果和模拟结果在平均晶粒尺寸方面符合较好
Using CellularAutomaton microstructure model, the 3D microstructure evolution of die-cast magnesium alloy was simulated. In the simulation process, the continuous nucleation model was used to treat the heterogeneous nucleation of liquid metal. The normal distribution function was used to describe the distribution of the density of nucleation sites with temperature, and the distribution function can be obtained by integrating the distribution function at a given degree of undercooling The nucleation density and grain growth model at the moment considered the growth kinetics of dendritic tip and the preferred growth direction <10 10>, and also considered the influence of temperature field and completed the coupling of macro-temperature field and microscopic calculation. Finally, the simulation results were verified by the metallographic test of die-cast magnesium alloy standard tensile test rod. The experimental results and simulation results are in good agreement with the average grain size