Section thickness-dependent tensile properties of squeeze cast magnesium alloy AM60

The development of alternative casting processes is essential for the high demand of light weight magnesium components to be used in the automotive industry,which often contain different section thicknesses. Squeeze casting with its inherent advantages has been approved for the capability of minimizing the gas porosity in magnesium alloys.For advanced engineering design of light magnesium automotive applications,it is critical to understand the effect of section thickness on mechanical properties of squeeze cast magnesium alloys.In this study,magnesium alloy AM60 with different section thicknesses of 6,10 and 20 mm squeeze cast under an applied pressure of 30 MPa was investigated.The prepared squeeze cast AM60 specimens were tensile tested at room termperature.The results indicate that the mechanical properties including yield strength(YS),ultimate tensile strength(UTS)and elongation(A)decrease with an increase in section thickness of squeeze cast AM60. The microstructure analysis shows that the improvement in the tensile behavior of squeeze cast AM60 is primarily attributed to the low-gas porosity level and fine grain strucuture which result from the variation of cooling rate of different section thickness.The numerical simulation(Magmasoft)was employed to determine the solidification rates of each step,and the simulated results show that the solidification rate of the alloy decreases with an increase in the section thickness.The computed solidification rates support the experimental observation on grain structural development.

塑料件有限元建模新技术研究

塑料件因其密度小、质量轻等特点被广泛的应用,成为汽车中不可缺少的一部分。同时塑料件具有厚度多变,结构特征复杂的特性,使其有限元建模相对钣金件建模更复杂和耗时,为提高建模效率缩短建模周期本文基于大型前处理软件ANSA介绍了塑料件有限元建模新技术,并通过模态、刚度、接触力和加速度等不同维度验证了新技术的可行性。新技术不仅提高了建模效率,同时也保证了仿真精度。