Microstructure, texture and mechanical properties of as-extruded Mg–Zn–Er alloys containing W-phase

Abstract

In the present work, the microstructure, texture and mechanical properties of as-extruded Mg–xZn–xEr (x=2, 4 and 6) alloys were investigated. The results showed that the W-phase in the as-cast alloys was destroyed during hot extrusion process. The distribution of the W-phase is more uniform when the extrusion temperature is 400°C, and the texture has also been a certain degree of weakening. With increase in the volume fraction of the primary W-phase, the particle-stimulated nucleation (PSN) of recrystallization was activated. It was suggested that the recrystallization via PSN should lead to weak texture. Good matching between strength and elongation is achieved in the Mg–6Zn–6Er alloy extruded at 400°C, of which the ultimate tensile strength (σb) and the yield tensile strength (σ0.2) were 328 (±2.5)MPa and 283 (±2.2)MPa, respectively, companying with an elongation of 19.7% (±1.2).