Boundary migration under an electric field was investigated in pure, TiO2-doped and Li2O-doped specimens. The boundary migration rates in doped specimens were much faster than those in pure Al2O3. In all specimens, the migration rate depended upon the applied bias direction. When compared with pure material, the dependence of boundary migration on the bias direction became more marked in TiO2-doped samples, but less marked in Li2O-doped material. The results were explained in terms of variations in the grain sizes, mobility and electrostatic potential of boundaries; caused by doping.

Effect of Titania and Lithia Doping on the Boundary Migration of Alumina under an Electric Field. J.I.Choi, J.H.Han, D.Y.Kim: Journal of the American Ceramic Society, 2003, 86[4], 640-3. See also: Journal of the American Ceramic Society, 2003, 86[2], 347-50