Transformation Plasticity at High Strain Rate in Magnesia‐Partially‐Stabilized Zirconia

Transformation plasticity in magnesia‐partially‐stabilized zirconia (Mg‐PSZ) is studied using a split Hopkinson pressure bar modified for ceramic materials. Axial and transverse strains are measured under uniaxial compressive loading at a strain rate of 250/s. The transformation yield stress is found to increase from 900 MPa under quasi‐static loading to 1.2 GPa at high strain rate. Post‐yield deformation is characterized by shear and volumetric plastic strains up to 1.2%. During unloading, the axial and transverse plastic strains are partially recovered while the volume is conserved. Axially oriented microcracks are observed but they do no contribute significantly to plastic deformation in Mg‐PSZ.