论述了一种新型高效的磷变质剂。试验结果表明 :用 PM对 Al-2 0 Si过共晶合金进行处理后 ,具有良好的变质效果 ,变质前 ,初晶 Si呈粗大六角形板片状 ,共晶 Si呈粗大针状 ,平均晶粒尺寸约为 2 50μm;变质后 ,初晶 Si和共晶 Si都很细小 ,呈块状和短棒状 ,晶粒尺寸干砂型为 4 0～ 50 μm,金属型为 2 0～ 30 μm。用 PM变质后 ,熔体氢含量减少 A new and efficient phosphorus modifier is discussed. The experimental results show that the PM has good metamorphic effect after Al-2 0 Si hypereutectic alloy treatment. Before modification, the primary Si is coarse hexagonal plate-like, eutectic Si is coarse needle-like, the average crystal The grain size is about 250μm. After modification, the primary Si and the eutectic Si are very fine, with massive and short rod shape. The grain size is 40 ~ 50 μm for dry sand and 20 ~ 30 μm for metal. With PM metamorphism, the melt hydrogen content decreased