Spinning spraying processing used for degassing treatment of AZ91D Mg alloy was researched. Pressure-reduction solidification is used to assess the efficiency of the degassing process and the optimal degassing time is determined. The mechanical properties and the microstructure of the alloy samples before and after degassing treatment in metal mold casting and in low pressure sand casting were studied

respectively. The results show that the tensile strength of the alloy samples treated by spinning spraying for 30 min can be considerably improved both in metal mold casting and in low pressure sand casting

particularly sharply improved in elongation. Based on the experimental results

it is concluded that the spinning spraying can rapidly and obviously reduce the gas content in Mg alloy

improving the mechanical properties

which is a desirable processing for refining Mg alloy melt.