The effects of Mg2+, Sr2+, Sc3+, Yb3+, Gd3+, La3+, Ti4+, Zr4+, Ce4+ and Nb5+ upon the grain boundary mobility of dense Y2O3 were investigated at temperatures ranging from 1500 to 1650C. In all cases, parabolic grain growth was observed for grain sizes that ranged from 0.31 to 12.5. The results suggested that interstitial transport was the rate-limiting step for diffusion in this material. The effect of solute drag could not be determined, but an anomalous effect of undersized dopants (Ti, Nb) upon diffusion enhancement, previously reported in CeO2, was confirmed. Signs of a very high binding energy between aliovalent dopants and O defects were also observed.

P.L.Chen, I.W.Chen: Journal of the American Ceramic Society, 1996, 79[7], 1801-9