过热与混溶处理对Al-30%Si合金微观组织的影响

Effect of overheating and miscibility process on microstructure of Al-30%Si alloy

对Al-30%Si合金进行过热处理及高低温溶体混溶处理,观察分析其微观组织的变化.结果表明:过热度温度区间为200~500℃时,随着温度的逐渐升高,初晶硅的平均尺寸略有减小,但形态依然为板片状和五瓣星状,而共晶硅的尺寸与形貌基本保持不变;高低温熔体混溶处理对合金组织的改善作用有限,在低温熔体温度为760℃时效果较好,初晶硅平均尺寸略有减小,五瓣星状的初晶硅基本消失,但共晶硅的尺寸与形貌未变.

The effects of heat treatment and high-temperature solution miscible treatment on the microstructure of Al-30%Si alloy were investigated.The results show that the average size of primary silicon decreases slightly with the increase of heat in the temperature range of 200~500℃,but the morphology is still plate-like and five-petal,and eutectic.The size and morphology of silicon remain basically unchanged.The high-low temperature melt-mixing treatment has limited improvement on the alloy structure.The effect is better when the low temperature melt temperature is 760℃.The average size of primary silicon is slightly reduced.The petal-like primary silicon has basically disappeared,but the size and morphology of the eutectic silicon have not changed.