浇注长度对流变压铸AlSi9Mg组织及性能的影响

采用自制的倾斜流变装置制备半固态合金熔体并直接进行流变压铸,研究了浇注长度对半固态AlSi9Mg组织及性能的影响。结果表明:浇注长度对抗拉强度和伸长率影响较大,对硬度和冲击韧性影响较小。浇注长度为500 mm时,抗拉强度为290 MPa,延伸率为4.1%,硬度为77.9HBS,冲击韧性为0.72 kJ/m2。流变压铸后AlSi9Mg组织晶粒尺寸明显减小,形状明显圆整。浇注长度为500 mm时,流变压铸组织中的初生固相平均尺寸为7.1μm,形状因子为0.73。

Influence of pouring length on rheo-die casting microstructures and properties of AlSi9Mg

The influence of pouring length on the rheo-die casting microstructure and properties of AlSi9Mg have been researched by rheo-die casting method after semi-solid AlSi9Mg alloy melt prepared into by incline cooling and shearing device.The results show that the pouring length has great influence on the tensile strength and the elongation percentage,but little on the hardness and the impact toughness.When the pouring length is 500 mm,the tensile strength is 290 MPa,the elongation percentage is 4.1%,the hardness is 77.9 HBS and the impact toughness is 0.72 kJ/m2.After rheo-die casting,the grain size of AlSi9Mg becomes smaller significantly and the shape becomes more round.When the pouring length is 500 mm,the average diameter of primary solid phase is 7.1 μm and the shape factor is 0.73.