Role of Y on the microstructure, texture and mechanical properties of Mg-Zn-Zr alloys by powder metallurgy

Ultra-fined Mg-5.1 wt% Zn-0.18 wt% Zr-3wt.% Y alloys (denoted as MY) were successfully fabricated via powder metallurgy (PM). The grain refinement, texture evolution, and twinning behaviors were systematically studied. Relationship between texture evolution and microscopic deformation mechanism is also discussed herein. Rare element (Y)-containing alloys with uniformly equiaxed fine grains exhibited weaker texture intensity. Deformation twinning in compression was hardly activated and replaced by dislocation and prismatic slips. The combined effect of the added Y and grain refinement resulted in the simultaneous enhancement of strength and ductility, especially for the compressive yield strength of the extruded alloy. And the tension/compression asymmetry of the material was significantly reduced due to the changed deformation mechanism. (C) 2019 Elsevier B.V. All rights reserved.