The effect of lutetium doping on the transient creep in fine-grained single-phase Al2O3

The creep deformation in Fine-grained polycrystalline Al2O3 is highly suppressed by the addition of 0.1mol% LuO1.5. The transient creep behavior in undoped and Lu-doped Al2O3 was examined at the testing temperature of 1250 - 1350degreesC, and the data were analyzed in terms of the effect of stress and temperature on the extent of transient time and strain. The experimental data on the transient creep in the present materials shows a good agreement with the prediction from a time function of the transient and the steady-state creep associated with grain boundary sliding in fine-grained single phase materials. The difference in the transient creep between Lu-doped Al2O3 and undoped-one can be explained from the retardation of grain boundary diffusion due to the Lu3+ ions' segregation in the grain boundaries.