Electric current dependence of plastic flow behavior with large tensile elongation in tetragonal zirconia polycrystal under a DC field

This study systematically investigated the electric direct current (DC) dependence of the plastic flow behavior in a densified tetragonal ZrO2 polycrystal (TZP). Consequently, we observed an optimal current density for tensile ductility. The maximum elongation of 135% was achieved under the current density of 250 mA∙mm−2 at a furnace temperature of 1000°C and an initial strain rate of 1 × 10−3 s−1. The diffusional mass transport in the TZP was accelerated by the combination of Joule heating and applied current effect, resulting in a reduced flow stress and an improved ductility.