真空压铸工艺参数对AM50镁合金力学性能的影响规律

采用阶梯试验模具及AM50合金,进行了系统的真空压铸试验,实测了不同厚度的阶梯试样在不同工艺条件下的密度及力学性能,研究了高真空压铸工艺参数对AM50镁合金力学性能的影响规律.结果表明,随着型腔真空压力的降低,铸件密度、抗拉强度和伸长率均随之提高;铸造压力对力学性能的影响在真空压铸和常规压铸中遵循基本相同的规律,即增大铸造压力可以使铸件的致密程度、抗拉强度、屈服强度和伸长率得到提高;随着高速速度的增大,薄壁铸件的抗拉强度、屈服强度和伸长率均表现出明显的增加,这一点与常规压铸的规律相反.结合高真空和高速工艺,可以使薄壁铸件的抗拉强度和伸长率得到较为明显的提升.

Effects of Vacuum Die Casting Processing Parameters on Mechanical Properties of AM50 Magnesium Alloy

Systematic high vacuum die casting experiments were conducted using a step-shape die and AM50 magnesium alloy, and density and mechanical properties of the tested specimens with different thickness were measured under different die casting processing parameters to understand the effects of high vacuum die casting processing parameters on mechanical properties of AM50 alloy. The results reveal that with decreasing in vacuum pressure in cavity, density, tensile strength and elongation of the specimens are increased. With increasing in filling pressure, relative density, tensile strength, yield strength and elongation of the specimens are improved. With raising in injection velocity, tensile strength, yield strength and elongation of thin-walled castings are obviously improved, which is contrary to the conventional casting. Tensile strength and elongation of thin-walled castings can be greatly improved by high vacuum combining with high injection velocity.