In this article,semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring.The effects of pouring temperature and stirring power on the microstructure of the AlSi7Mg alloy slurry were studied.The results showed that the semi-solid AlSi7Mg alloy slurry,127 mm in diameter,could be pre- pared by using the low superheat pouring and weak electromagnetic stirring technology and this new technology could save energy and make the pouring process convenient. When the liquid AlSi7Mg alloy was poured at 650℃or 630℃,the solidified mi- crostructure of the AlSi7Mg alloy slurry,prepared by weak electromagnetic stirring, was remarkably improved when compared with that of the slurry prepared without stir- ring.The primaryα-Al grains appeared rosette-like or spherical.When the pouring temperature was decreased,the shape of the primaryα-Al grains gradually changed from dendritic-like grains to spherical grains.When the pouring temperature was appropriately increased,that is,raised to a certain superheat,the pouring process became easier and an ideal spherical microstructure of the AlSi7Mg alloy slurry,pre- pared by weak electromagnetic stirring,could also be obtained.In this experiment, when the stirring power was 0.36 kW,the optimized pouring temperature parame- ter was 630℃.When the AlSi7Mg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring,the pouring temperature was 630℃.Increasing the stirring power appropriately could gain better spherical primaryα-Al grains,but if the stirring power was increased to a certain value,the shape of the primaryα-Al grains did not improve further.In this experiment,the optimized stirring power parameter was 0.36 kW. In this article, semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring. These effects of pouring temperature and stirring power on the microstructure of the AlSi7Mg alloy slurry were studied. The results showed that the semi-solid AlSi7Mg alloy slurry, 127 mm in diameter could have been pre-pared by using the low superheat pouring and weak electromagnetic stirring technology and this new technology could save energy and make the pouring process convenient. When the liquid AlSi7Mg alloy was poured at 650 ° C or 630 ° C , the solidified mi-crostructure of the AlSi7Mg alloy slurry, was prepared by weak electromagnetic stirring, was remarkably improved when compared with that of the slurry prepared without stir- ring. The primary α-Al-pellet was rosette-like or spherical. When the pouring temperature was decreased, the shape of the primary α-Al grains gradually changed from dendritic-like grains to the spherical grains. ly increased, that is, raised to a certain superheat, the pouring process became easier and an ideal spherical microstructure of the AlSi7Mg alloy slurry, pre- pared by weak electromagnetic stirring, could also be obtained. 0.36 kW, the optimized pouring temperature parameter was 630 ° C.When the AlSi7Mg alloy slurry was prepared by low superheat pouring and weak electromagnetic stirring, the pouring temperature was 630 ° C. Increasing the stirring power are able could gain better spherical primary α-Al grains , but if the stirring power was increased to a certain value, the shape of the primary α-Al grains did not improve further.In this experiment, the optimized stirring power parameter was 0.36 kW.