Deformation Mechanism & Temperature Dependence of AZ31 Magnesium Alloy

Abstract

The deformation behavior of AZ31 Mg alloy is studied here in relation to the temperature. A rolled plate with a thickness of 50 mm was first homogenized at 400 A degrees C for 4 h before preparing test specimens with the tensile axis parallel to the rolling direction (RD). A series of tensile tests was then carried out at a strain rate of 10(-2)/s together with load relaxation tests to obtain flow curves in terms of the stress and strain rate at room temperature (RT), 100 A degrees C, 200 A degrees C, and 300 A degrees C. The flow curves were found to represent the usual grain matrix deformation (GMD) behavior, consisting of the accumulation and relaxation of glide dislocations at temperatures of less than 100 A degrees C. At temperatures greater than 200 A degrees C, grain boundary sliding (GBS) was found to play an important role, as described in theories related to an internal variable. The GBS could be characterized as a non-Newtonian viscous flow with a power index value of M (g) = 0.5.