Investigation on the inhomogeneous deformation of magnesium alloy during bending using an advanced plasticity model

Abstract

In the present work, an advanced plasticity model is established to character the anisotropic and asymmetric yielding and hardening behaviors of magnesium alloy. This model is comprised of the stress invariant-based Yoon2014 yield function, non-associated flow rule and yield surface-interpolation method in the description of distortional hardening. For effectively numerical implementation of the plasticity model, a semi-explicit stress integration scheme based on the return mapping method is provided. The implemented model is then applied to simulate the inhomogeneous deformations during three-point bending of an extruded magnesium alloy. Simulation results show that there are three distinct zones in the bent plate according to its deformation patterns, i.e., the compressive inner zone, the tensile outer zone, and the central zone which experiences tensile, then compressive and again tensile deformations. Compared to the counterpart Hill48 function, Yoon2014 function has better performance in simulating the inhomogeneous deformations of magnesium alloy.