Preparation of semi-solid AlSi7Mg alloy slurry with big capability

Abstract

Semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak traveling-wave electromagnetic stirring. The effects of pouring temperature and stirring power on the microstructure of AlSi7Mg alloy slurry were studied. The results show that the semi-solid AlSi7Mg alloy slurry of 5 kg can be prepared. This new technology can save energy and make the pouring process convenient. When the pouring temperature is decreased at a stirring power of 0.41 kW, the shape of primary α-Al grains gradually changes from dendritic-like to spherical. When the alloy melt is poured at the temperature (630°C) with a certain superheat, the pouring process becomes easier, and the spherical microstructure of AlSi7Mg alloy slurry can be prepared by the weak traveling-wave electromagnetic stirring. When the pouring temperature is 630°C, increasing the stirring power appropriately can result in better spherical primary α-Al grains, but if the stirring power is increased to a certain value (1.72 kW), the shape of primary α-Al grains does not obviously improve when the stirring power is continually increased.