超声波导入时初始温度对铝-硅合金组织的影响

摘要

采用高能超声波对Al-20％Si合金进行处理，控制Al-20％Si合金熔体温度在620～680℃，研究合金组织随超声波导入时熔体初始温度的变化规律。实验表明，随着导入超声波时熔体温度的升高，初晶硅形貌由粗大的板片状逐渐变成细小的颗粒状，超声波处理熔体的温度控制在660℃左右时，初晶硅的组织细小、圆整度高、分布均匀。%Influence rules of the mierostructures of Al-20%Si alloy treated by high-intensity ultrasonic in the starting tern perature ranges between 620 ℃ and 680 ℃ were studied. The mechanism of microstructural refinement for the ultrasonic treated alloy was also discussed. With the rise of starting temperature the morphology of primary crystal silicon changed by a thick sheet into small particles gradually. The results indicated that finer primary phase could be obtained when the starting tempera ture was at about 660℃.