【摘要】 分别对亚共晶Al 6Si合金和共晶Al 12 .6Si合金进行Na变质处理,发现对于亚共晶Al 6Si合金,重熔使Na变质失效,而施加静磁场条件下,重熔没有使Na变质失效。对于共晶Al 12 .6Si合金,同样在变质剂反应温度保温2 0min ,施加静磁场的条件下,共晶硅细化,并呈现一定程度的粒状化,其变质效果明显优于不施加静磁场的情况。延长保温时间至40min ,不施加静磁场时出现了变质衰退现象。但在施加静磁场条件下,变质衰退现象相对较轻,即静磁场具有延长变质有效时间的作用。分析认为这是静磁场抑制对流作用的结果。更多还原

【Abstract】 Hypereutectic Al-6Si alloy and eutectic Al-12Si alloy were modified with Na respectively.It was found that the Na modification is failure with refusing without static magnetic field for the hypereutectic Al-6Si alloy,in turn with the static magnetic,Na modification keeps the effects.Eutectic Si was fined and showed a certain granularity under static magnetic field at holding time for 20 min for eutectic Al-12Si alloy,which indicated better modification effects than that without static magnetic field.Modification fades are heavy in the Al-12Si alloy without static magnetic field at holding time for 40min while slight with static magnetic field.The above results indicated that the static magnetic field can improve the modification effects.It is due to the fact that the static magnetic field can restrain the conversion.更多还原