过共晶铝硅合金对铝合金的变质作用研究

半固态加工技术中的一个关键问题就是如何制备优质的半固态合金棒坯料.通过在亚共晶Al-Si合金熔液中搅入初生Si相为颗粒状的过共晶Al-Si合金,使颗粒状Si相在液相线温度下扩散到熔液中,成为形核质点,抑止枝晶组织的形成,从而获得满足半固态加工要求的非枝晶组织.结合电镜分析结果,对变质作用的机理进行了初步分析.

Study on the Modification of Hyper-Eutectic Al-Si Alloy to Aluminum Alloy

The key question of the semisolid process technology is how to prepare high quality semisolid alloy stock. During the preparation process of semisolid stock, the transcocrystallized Al-Si alloy was mixed into the semi-solid state hypoeutectic Al-Si alloy molten, which Silicon phase is graininess, and the non-arborescent structure could be gotten through the diffusion of the silicon phase into the molten under the liquid line temperature, which becomes the nucleation point and breaks the continuous growth of the arborescent structure. This new method is very simple and easy to operate. It is adapt to the production of the domestic small and medium-sized enterprise, and has the practice meaning of cost reduction and increasing the cast quality.