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

Abstract

Anisotropic strainhardening behavior of the TX51 (Mg–5Sn–1Ca) magnesium alloy sheets was investigated in the temperature range of 25–300 آ°C and at an initial strain rate of 5 أ— 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 strainhardening behavior of the sheets after hot rolling and annealing. The anisotropic strainhardening 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 strainhardening behavior at all test temperatures. The directionality of flow stress and initial strainhardening rates in stage III were discussed based on the Schmid factors of material.