(河北科技大學(xué)材料系，石家莊 050054
北京科技大學(xué)鑄造研究所，北京 100083)
摘 要: 利用定量金相技術(shù)研究了亞共晶鋁硅合金在磁攪拌連續(xù)冷卻過程中一次固相的形成及演變規(guī)律。結(jié)果表明，一次固相首先在型壁上形核和長(zhǎng)大，并具有粒狀、條狀和樹枝狀三種形態(tài)。隨后，在攪拌作用下從型壁上脫落進(jìn)入熔體內(nèi)部，隨熔體做整體運(yùn)動(dòng)的同時(shí)還會(huì)發(fā)生自旋運(yùn)動(dòng)。運(yùn)動(dòng)過程中，粒狀晶向球形演變，條狀和樹枝狀游離晶則會(huì)發(fā)生頸縮和熔斷，增殖為若干個(gè)小的粒狀晶，并最終演變成以近球形粒狀非枝晶為主的演變組織。
關(guān)鍵字: 鋁硅合金 固相形成與演變 非枝晶組織 半固態(tài)漿料制備
（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
