Simulation of mechanical behavior ofAZ31 magnesium alloy during twin-dominated large plastic deformation
(College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China)
Abstract: Experiments and visco-plastic self-consistent (VPSC) simulations were used to quantify the amount of twinning and the relationship to stress-strain behavior in a textured Mg-3Al-1Zn plate. Two different compression directions were utilized to favor extension or compression twinning. twins nucleate at the beginning of plastic deformation and grow to consume the parent grains completely. During compression along the normal direction, twinning and - double twinning start at strain of 0.05, and the number of twins increases until rupture, above strain of 0.15. and - twinning also occur during compression along the transverse direction, start at strain of 0.06 and then multiply in grains totally reoriented by twins. Using suitable parameters, the VPSC model can accurately predict the occurrence of extension, compression and double-twinning as well as the flow stresses and deformed textures. According to VPSC simulations, twinning and slip have the same latent hardening parameters.
Key words: AZ31 magnesium alloy; twinning; crystal plasticity; plastic deformation