Varying strain rates and elevated temperatures effects on the mechanical properties of AZ31B magnesium alloy

This study investigates the monotonic tensile behavior of magnesium (Mg) alloy AZ31B across a temperature range from ambient (25 degrees C) to elevated (up to 300 degrees C) with varying strain rates (SR) (1.5 x 10-2 to 1.5 x 10-4 s-1). Mechanical properties such as ultimate tensile strength (sigma u), tensile yield strength (sigma y), strain to failure (epsilon f), plastic anisotropy (r-value), strain rate sensitivity (m) and strain hardening exponent (n) were investigated in this study for these strain rates. As the temperature increased from 25 to 300 degrees C, the following changes in mechanical properties were observed: the yield strength (sigma y) decreased by 84.50%, the ultimate tensile strength (sigma u) decreased by 87%, the modulus of elasticity (E) decreased by 63.0%, and the elongation increased by 72.0%. The reduction factors (RF) were proposed for the above-mentioned mechanical properties for varying temperature ranges. The impact of varying temperatures and strain rates on fracture surfaces was investigated using field emission scanning electron microscopy (FE-SEM). The results revealed the presence of tenacity nets, cleavage patterns, and an increasing number of dimples as temperatures increased.