Microstructural evolution and deformation behaviour of wrought Mg–Al–Zn alloys under dynamic compression

Abstract

We perform dynamic compression to extruded AZ31 Mg alloys both along and perpendicular to the extrusion direction (ED) at a high strain rate of 1400 s⁻¹ using split Hopkison pressure bar, and study the microstructure, texture evolution and mechanical anisotropy. We find that the temperature and loading direction play an important role in affecting microstructure evolution and flow stress. The mechanical anisotropy, yield strength and hardening ability are found to decrease with the rise of temperature. Moreover, the grains are also found to be refined remarkably, and the strong basal texture is weakened substantially owing to the dynamic recrystallisation especially in the case where dynamic compression is carried out perpendicular to the ED at 473 K.

Keywords:

• Magnesium alloy
• Dynamic compression
• Grain refinement
• Texture evolution
• Mechanical anisotropy

Acknowledgments

This work was supported partly by National Natural Science Foundation of China (Grant No. 51505143) and Hunan Provincial Natural Science Foundation of China (Grant no. 14JJ3111) and Scientific Research Fund of Hunan Provincial Education Department (Grant no. 14C0455). Z.C.W. thanks financial support from the Grant-in-Aid for Young Scientists (A) (grant no. 24686069).