磷、锶复合变质对Al-24%Si合金组织形貌的影响

Effect of P,Sr and Their Composite Modifier on Microstructure of Al-24% Si Alloy

探讨了磷、锶及其复合变质加入顺序对Al-24%Si合金组织形貌的影响。结果表明:磷对初晶硅的细化起作用;锶对共晶硅起细化作用,但能裂解初晶硅。先加磷后加锶复合变质时,共晶硅呈圆点状,细化作用较单一锶变质时好,但对初晶硅的细化变质效果不明显;先加锶后加磷复合变质时,初晶硅的尺寸更加细小,其变质效果较单一磷变质好,但对共晶硅的作用不明显。

The effects of phosphorus, strontium and their composite modifier on microstructure of Al-24%Si alloy was studied. The results show that phosphorus plays a major role in refining primary silicon, while strontium aims at refining eutectic silicon. The effect of refining eutectic silicon with adding phosphorus first and then adding strontium is more obvious than with single strontium, eutectic silicon is round-point, while it＇s not clear in the further refining primary silicon. On the contrary, the effect of refining primary silicon with adding strontium first and then adding phosphorus is more obvious than with single phosphorus, but it＇s not distinct in the further refining eutectic silicon.