The hot deformation behavior, microstructure and texture evolution of homogenized Mg–9Li–1Zn alloy

Abstract

In this study, the hot deformation behavior, microstructure and texture evolution of Mg–9Li–1Zn (LZ91) alloy were investigated systematically, and the best Arrhenius hot deformation constitutive equation model and processing map of the LZ91 alloy were developed. Hot compression tests were performed at deformation temperatures and strain rates ranging from 175 °C to 275 °C and 0.001 s−1 to 1 s−1, respectively. The results showed that Arrhenius constitutive equation can predict accurately the hot deformation behavior of LZ91 alloy. The instability areas for this alloy were concentrated in the range of 175 °C–220 °C, 0.01 s−1–0.1 s−1 and 225 °C–260 °C, 0.001 s−1–0.002 s−1 and 0.02 s−1–1 s−1. The observation of microstructure revealed that the alloy is deformed by the cooperation of the basal slip system and the pyramidal conical slip system. In addition, the hardness which increases in a gradient from the center to the edges is the result of the combined effect of grain refinement and texture.