The application of electric fields to ceramics can give rise to plasticity in materials that traditionally exhibit no plastic deformation. High homologous temperatures are, however, typically necessary to achieve significant plastic deformation in ceramic materials. Plastic deformation ceramic oxides was found by Conrad et al. to occur under relatively modest electric field strengths (0.02-0.32 ). Strain-mediating defects such as vacancies and dislocations tend to be charged in ceramic materials due to the ionic or covalent nature of bonding. Thus, the movement of electrons can have a direct impact on the mobility of these defects in ceramics and subsequent plastic deformation. The primary effect of the electric field in the deformation of fine-grained ceramic oxides is to shift the diffusion pathway from bulk diffusion to grain boundary diffusion, resulting in greater diffusion and easier grain boundary sliding.