Influence of Rolling Temperature on the Mechanical Properties and Microstructure of Variable-Plane-Rolled Mg-3Al-1Zn Alloy

Abstract

AZ31 magnesium alloy was produced via variable-plane rolling (VPR) under different temperatures. The effects of rolling temperature on the microstructure, texture and mechanical properties were investigated. A double-peak basal texture was formed during VPR treatment. Dynamic recrystallization (DRX) was observed during the VPR treatment, and it can reduce the texture intensity owing to the coalescence of sub-grains. Four types of twins were observed in the VPR treatment: {10-12} extension twins, {10-13}, {10-11} contraction twins and {10-11}-{10-12} double twins. The suitable temperature of AZ31 magnesium alloy for VPR treatment is determined as 623\xa0K through experiments with tensile yield strength of 240\xa0MPa, compressive yield strength of 162\xa0MPa and elongation of 13%. Owing to the important impact of temperature on mechanical properties, the alloy was further VPRed with a decrease in temperature pass-by-pass. The high temperature of 623\xa0K at the initial passes randomized the texture, which led to notably high ductility.