Effect of Pouring Temperatures on the Microstructures of the Semi-Solid AlSi₇Mg Alloy

The effect of different pouring temperatures on the microstructures of AlSi₇Mg alloy has been researched. When the pouring temperature is close to the liquidus temperature of AlSi7Mg alloy, the primary α-Al in the billets of A1Si7Mg alloy solidifies into spherical or nodular grains which are small and distributed homogeneously. In order to obtain non-dendritic semi-solid billets, the appropriate pouring temperature is 615℃. The faster cooling rate,the melt flowing and larger solidification region induced by the near liquidus pouring temperature promotes the formation of spherical or nodular primal α-Al.