Microstructure and mechanical properties of equal channel angular pressed Mg–Y–RE–Zr alloy

Abstract

The microstructure and mechanical properties of equal channel angular pressed (ECAP) Mg–Y–RE–Zr alloy (WE43) are examined. Results show that after ECAP, the average grain size remarkably decreases from ∼50 µm at initial state to ∼1.5 µm through ECAP for four passes and the homogeneity of microstructure also improves gradually. Meanwhile the secondary-phase β-Mg5RE morphology has obvious transformation from plate-like to spherical. Moreover, the initial random texture is converted to the strong (0002) basal texture. The ultimate tensile strength and yield strength increase in all passes. However, the ductility exhibits a tendency of increase from 1 to 4 passes then decrease from 4 to 12 passes. The variation in strength and ductility is attributed to the effect of specific microstructure evolution.