采用固液混合铸造的Al-40Si合金组织细小,合金力学性能明显优于传统铸造和半固态加工合金,并且解决了传统铸造Al-40Si合金铸件难以热加工的问题。在本工艺条件下,当添加平均粒度为120μm的粉末且粉末添加量与合金熔体质量比为1时,Al-40Si合金中的初晶硅平均粒度可控制在30μm以下;材料的室温力学性能为:σb=119.6MPa,σ0.2=105MPa,δ=1.43%。
A novel mixed solid-liquid casting was utilized to prepare Al-40Si alloy. The results shows that the Al-40Si alloy has a finer microstructures and higher mechanical properties than by the conventional casting and semi-solid casting technologies. It can successfully resolve the problem difficult to hot-process for Al-40Si alloy prepared by conventional casting. The mean size of primary Si in the alloy can be controlled under 30μm with the mechanical properties of σb=119.6 MPa, σ0.2=105MPa, δ=1.43% at room temperature when the mass ratio of alloy powder is 1.