(河北科技大学材料系，石家庄 050054
北京科技大学铸造研究所，北京 100083)
摘 要: 利用定量金相技术研究了亚共晶铝硅合金在磁搅拌连续冷却过程中一次固相的形成及演变规律。结果表明，一次固相首先在型壁上形核和长大，并具有粒状、条状和树枝状三种形态。随后，在搅拌作用下从型壁上脱落进入熔体内部，随熔体做整体运动的同时还会发生自旋运动。运动过程中，粒状晶向球形演变，条状和树枝状游离晶则会发生颈缩和熔断，增殖为若干个小的粒状晶，并最终演变成以近球形粒状非枝晶为主的演变组织。
关键字: 铝硅合金 固相形成与演变 非枝晶组织 半固态浆料制备
（Department of Materials Science and Engineering,
Hebei University of Science and Technology, Shijiazhuang 050054, P. R. China
* Foundry Institute, University of Science and Technology Beijing, Beijing 100083, P. R. China）
Abstract:The formation and evolution of primary phase solid of hypo-eutectic Al-Si alloy in the condition of continuous cooling and stirring have been explored by means of quantitive metaloscopy, the obtained results showed that the primary phase particles are mainly nucleated on the surface of stirring chamber, and their initial forms may be shot bar of dendritic. All of them can be dropped off by the stirring force and then suspended into the melt, the suspended shot particles can be sphered step by step during their rotation around their center and their motion with the melt. The suspended bar and dendritic solid also can be sphered through necking, remelting and breeding, therefore the final structure mainly consists of nondendritic spheroidal grain, which is named rheologic structure.
Key words: Al-Si alloy; formation and evolution of solid; non-dendritic structure; making semi-solid metal slurry
