Influence of thermomechanical processing on microstructure, mechanical and strain hardening properties of single-phase Mg-4Li-0.5Ca alloy for structural application

Abstract

The single-phase Mg- 4Li- 0.5Ca alloy was rolled at three different temperatures (250, 300 and 350 °C) and followed by annealing at 200 °C for 10 min. To evaluate the mechanical properties, the tensile test was conducted at a constant strain rate of 10−3 s−1. Factors influencing the tensile strength and strain hardening properties were assessed by microscopy, XRD and EBSD analysis. Besides, Kocks–Mecking plots (K-M) were used to determine the different stages of strain hardening exhibited by the variously processed Mg- 4Li- 0.5Ca alloy test specimens. The ultimate tensile strength has decreased as hot-rolling temperature increases with increased ductility. The strain hardening properties such as hardening capacity (Hc), strain hardening exponent (n) are increased significantly with an increase in hot rolling temperature and subsequent annealing.

Keywords

• Mg-4Li-0.5Ca
• Hot rolling
• Twins
• Mg2Ca
• Hardening capacity