Microstructural Evolution during Tensile Deformation in TRC-ZA21 Magnesium Alloy with Different Loading Directions and Strain Rates

The variation of texture characteristics and activation of deformation mechanism in magnesium alloys can be achieved by addition of RE and Ca elements and subsequently affect the microstructure evolution during deformation process. In this manuscript, the effects of loading direction and strain rate on mechanical properties, microstructural characteristics, texture evolution and deformation mechanism in TRC-ZA21 magnesium alloy sheet were investigated. Moreover, orientation dependence and strain rate sensitivity of deformation mechanism were also discussed. The results showed that evident difference in mechanical properties in TRC-ZA21 alloy exhibited by the changes in loading direction and strain rate. The variations in grain orientation and basal texture characteristic were attributed to the grain rotation behavior during the plastic deformation, dominated by deformation mechanism. Basal slip, extension twinning and prismatic slip played different contributions to plastic deformation behavior and presented orientation dependence and strain rate sensitivity. The activities of prismatic slip and extension twinning both enhance with increasing strain rate. The phenomenon of weakened effect of twinning and promoted role of prismatic slip was presented to coordinate strain compatibility during plastic deformation.