Abstract
The high temperature plastic flow in polycrystalline oxide ceramics such as Al2O3 and TZP is very sensitive to small level of doping by various cations. High-resolution transmission electron microscopy observation and nano-probe energy-dispersive X-ray spectroscopy analysis revealed that dopant cations tend to segregate along the grain boundaries. The dopant effect is caused by change in the chemical bonding state in the vicinity of grain boundaries segregated with dopant cations. The electronic structure in the vicinity of the grain boundaries is one of the critical factors to determine the high temperature plasticity in oxide ceramics.
