Deformation mechanism of AZ91 alloy during compression at different temperatures

Abstract In this study, two AZ91 samples were produced by compression at 200 °C and 350 °C, respectively. The microstructure of the samples and their effect on deformation were studied. The results show that the deformation mechanism is slipping, twinning and shear banding at low temperature due to the low compression temperature. The stacking fault energy of alloy can be increased by the increase of adiabatic temperature, the dislocations gather at the shear band, resulting in the increase of hardness, which is not conducive to deformation. At high temperature, there were a large number of fine second phases precipitated at the shear bands. This second phase provides nucleation site for recrystallization, and dislocation energy storage in the shear band provides energy for recrystallization, resulting in recrystallization nucleation and growth at the shear bands. Discontinuous dynamic recrystallization weakened texture intensity.