Mechanical properties and texture of a superplastically deformed AZ31 magnesium alloy

Room temperature tensile properties of a superplastic AZ31 magnesium alloy prior to and following high temperature deformation at 673 and 723 K were examined. The material behaved in a superplastic manner at low strain rates, and dislocation creep dominated deformation at high strain rates. The specimens after high temperature deformation exhibited higher ductility and lower strength as the strain rate during high temperature deformation decreased. Pre-existing basal texture changed gradually toward random during high temperature deformation at low strain rates, whereas it was strengthened at high strain rates. Both the basal texture weakening and lower cavity volume fraction brought about the higher ductility following superplastic deformation at lower strain rates.