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 .

中文翻译：

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Mg-Si-Sr合金的热变形行为和组织演变

Mg-0.55 wt。％Si-0.75 wt。％Sr合金在250℃，压缩应变率为1 s -1，0.1 s -1，0.01 s -1和1 s时的热变形行为和微观组织演变。通过电子背散射衍射（EBSD）研究了0.001 s -1。随着压缩应变率的降低，相应的显微组织表现出细化了基体中的晶粒。结果表明，热变形有效地促进了晶粒的破碎和动态再结晶，从而导致晶粒取向偏斜和织构强度减弱。在热变形的初始阶段，棱柱形的<a>滑动和金字塔形的<c + a>滑动被激活。此外，由于热变形期间的加工硬化行为，压缩应变率为1 s -1，屈服强度显着增加到90 MPa。