| In this paper, the strain-rate effects of the AZ31 alloy under impacting loading was studied by SHPB technique at room temperature. From the observations of the microstructure of AZ31 alloy, the structural evolution in the course of plastic deformation at high-strain-rate and dynamic stress-strain behavior were analyzed. The general SHPB technique was modified to meet the stress equilibrium of the specimen and decrease the dispersion of the elastic wave, these factors have influence on the experimental results of the AZ31 alloy. In order to study the plastic deformation mechanisms, the microstructure of cross section and longitudinal section were studied by optical microscopy. At the same time, the rolling AZ31 targets was penetrated by tungsten alloy projectile with ballistic gun. Microstructure in the two experiments was compared. The results have been obtained show that the AZ31 alloy displays obvious positive strain-rate effect and dynamic recrystallization occurred when the specimens were compressed. The fracture character is along the 45 0direction of the loading. The plastic deformation mechanisms are dislocations moving and grain boundary sliding. The melted and rapid solidification layer, fine grained layer and deformed layer were observed after penetration.
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