Elevated-Temperature Deformation Behavior and Microstructural Evolution of Mg–3Al–1Zn Alloy

Abstract

Magnesium (Mg) and its alloys are promising materials for many new and advanced applications because of their natural abundance, low density, and good thermomechanical properties. In this study, the elevated-temperature deformation behavior of Mg alloys in addition to their formability and high-temperature application range was assessed between 250 and 400 °C and at different strain rates between 1 × 10−3 and 5 × 10−5 s−1. An elevated-temperature constitutive equation, which addresses and describes the elevated-temperature deformation mechanism, was obtained. Moreover, the related Zener–Hollomon parameter was experimentally established for the selected Mg alloy. The activation energy of the investigated alloy was determined to be 120.7 kJ/mol. According to the results, the activation energy was found to be very similar to the activation energy of self-diffusion for Mg alloys. The evolution of the non-deformed microstructure of the as-received sample within the investigated temperature range was also studied, and the relevant mean linear intercept grain size was estimated. Mechanical property deterioration was investigated, and the relevant microstructures were characterized.