Study on heterogeneity of microstructures and properties of as-extruded EW83 magnesium alloy plate

Heterogeneity of microstructure and mechanical properties of the as-extruded EW83 magnesium alloy plate was investigated by means of OM, SEM, EDS, XRD and hardness testing. It is found that heterogenous evolution of the microstructures are affected by the recrystallization and precipitation particle. In the edge of the plate, because of the grain refining effects resulted from the increase of the real Z parameter (heavy shear deformation and quick decrease of temperature), the hindering motion of the grain growth by the precipitation particles, and the recrystallization by particles stimulated nucleation (PSN), the measured grain size is half of the predicted one by the mean parameter (Z). In the middle of the plate, because of the grain coarsening effects caused by the decrease of the real Z parameter, static recrystallization, the measured grain size is twice times as the predicted one by the Z. The hardness value of the specimens cutting from the edge of the as-F plate increases by 5% than those of the middle one. However, after aged at 215°C, the peak hardness of the specimens cutting from the middle of the as-T6 plate increases by 10% than that of the edge one.