Effect of pre-deformation on microstructure and mechanical properties of WE43 magnesium alloy II : Aging at 250 and 300 °C

In this work, the microstructural evolution and mechanical properties of a pre-deformed WE43 magnesium alloy when aged at 250 and 300 °C were further investigated. It is found that the abundant deformation twins introduced by pre-deformation were maintained within the alloy during the aging treatment. Second particles formed at the twin boundaries and coarsened with aging time, especially at 300 °C. When peak-aged at 250 °C, the fine metastable β″′ and β′ precipitates formed in the un-deformed alloy have been transformed into relatively large β₁ and β precipitates by the pre-deformation. While peak-aged at 300 °C, the pre-deformation obviously refined the β precipitates. Mechanical properties indicate that pre-deformation can increase the yield strength by 19 MPa and 54 MPa for the peak-aged alloy at 250 °C and 300 °C, respectively, and will not obviously deteriorate the tensile elongations.