Hot deformation behaviors and microstructure evolution of Mg–Si–Sr alloy

The hot deformation behavior and microstructural evolution of as-extruded Mg-0.55 wt.%Si-0.75 wt.%Sr alloys at 250 °C with the compressive strain rate of 1 s ^−1 , 0.1 s ^−1 , 0.01 s ^−1 and 0.001 s ^−1 were investigated via electron backscatter diffraction (EBSD). As the compressive strain rate decreases, the corresponding microstructure exhibits that fined grains in the matrix. The results showed that the hot deformation effectively promotes the grain breakage and dynamic recrystallization, which result in the grain orientation deflection and the texture intensity weakened. The prismatic 〈a〉 slip and pyramidal 〈c + a〉 slip were activated at the initial stage of hot deformation. In addition, the yield strength was significantly increased to 90 MPa due to the work hardening behavior during hot deformation with a compression strain rate of 1 s ^−1 .