以过共晶Al-20%Si合金为研究对象,添加Al-P合金和Al-Ce合金作为变质剂,采用光学显微镜分析变质处理对显微组织的影响。研究结果表明,同时添加Al-Ce和Al-P对Al-20%Si合金进行复合变质,粗大块状初晶硅的尺寸明显减小,并转变为纤维状;针状共晶硅转变为短杆状或颗粒状,获得了良好的复合变质效果,最后对变质机理进行了探讨。 The hypereutectic Al-20% Si alloy was taken as the research object, Al-P alloy and Al-Ce alloy were added as the modifier, and the effect of the modification treatment on the microstructure was analyzed by optical microscope. The results show that Al-Ce and Al-P are added into the Al-20% Si alloy to compound metamorphism, the size of the coarse bulk primary Si obviously decreases, and it changes into a fibrous shape. The acicular eutectic silicon transforms into short Rod or granular, get a good composite metamorphism, and finally metamorphic mechanism were discussed.