Anisotropic Strain-Hardening Behavior of Mg–5%Sn–1%Ca Alloy Sheet at Elevated Temperatures

Abstract

Anisotropic strain-hardening behavior of the TX51 (Mg–5Sn–1Ca) magnesium alloy sheets was investigated in the temperature range of 25–300 °C and at an initial strain rate of 5 × 10−4 s−1. Tensile tests were carried out with the loading axis oriented at 0 deg, 45 deg, and 90 deg to the rolling direction (RD) to explore the effects of temperature on the anisotropic strain-hardening behavior of the sheets after hot rolling and annealing. The anisotropic strain-hardening behavior of the TX51 sheet was due to the crystallographic texture as well as mechanical fibering of the microstructure. The former was manifested by the development of a relatively sharp basal {0001} texture, and the latter was caused by alignment in the RD of CaMgSn coarse particles. Kocks–Mecking type plots showed stage III and stage IV strain-hardening behavior at all test temperatures. The directionality of flow stress and initial strain-hardening rates in stage III were discussed based on the Schmid factors of material.