基于数值模拟的汽车用蠕墨铸铁压盘铸件残余应力研究

Research on Residual Stress of Vermicular Graphite Cast Iron Pressure Plate Castings for Automobile Based on Numerical Simulation

利用ProCAST软件模拟压盘铸件的填充和凝固过程,分析充型时的温度场、凝固过程和凝固后的残余应力场以及加工面的变形场,得到压盘件整体的残余应力分布规律和变形量。结果表明:压盘铸件表面主要以拉应力为主,靠近内圆部分以及与冒口相连接的大凸耳部位残余应力偏大,存在裂纹倾向。压盘整个工作面残余应力分布不均匀,大致呈现出从内圈到外圈残余应力变小的规律。压盘工作面法向的变形程度不同(外凸内凹),导致整个盘面平面度精度降低。

The filling and solidification process of pressure plate casting was simulated by ProCAST software, and the temperature field, solidification process, residual stress field after solidification and deformation field of working surface were analyzed, the distribution law of residual stress field and the deformation amount were obtained. The results show that the surface of the pressure plate casting is mainly tensile stress, and the residual stress near the inner circle and the large lug connected with the riser is relatively large, and there is a tendency to crack. The residual stress distribution on the entire working surface of the pressure plate is not uniform, but it roughly shows a rule of decreasing the residual stress from the inner ring to the outer ring. The degrees of deformation and displacement in the normal direction of the pressure plate working surface is different(convex and concave), which leads to the decrease of the accuracy of the flatness of the whole plate surface.