Plastic deformation and constitutive modeling of magnesium-based nanocomposites

Abstract

The focus of this research effort is to investigate the response of AZ31 Mg alloy based nanocomposites to tensile and compressive plastic deformation and to develop a crystal plasticity model to capture the essential characteristics of the behaviour observed. AZ31 Mg alloy, reinforced by different volume fractions of 50-nm Al2O3 nanoparticles (1v%, 1.4v% and 3v%), were fabricated by a disintegrated melt deposition technique, followed by hot extrusion. The tensile and compressive mechanical behaviour of these materials at strain rates spanning 10-4 to 103 s-1 was investigated. A rate-dependent crystal plasticity model is developed and implemented in ABAQUS/Explicit (2010) finite element software via a user-defined material subroutine (VUMAT). The effect of the nanoparticles is captured by incorporating a term describing the interaction between the nanoparticles and slip/twinning in the hardening evolution laws for slip/twinning.