Transient creep in fine-grained polycrystalline Al2O3 with Lu3+ ion segregation at the grain boundaries

The creep deformation in fine-grained polycrystalline Al2O3 is highly suppr essed by the addition of 0.1 mol% LuO1.5. The transient creep behavior in L u-doped Al2O3 was examined at the testing temperature of 1250-1350 degreesC , and the data were analyzed in terms of the effect of stress and temperatu re on the extent of transient time and strain. The experimental data on the transient creep in Lu-doped Al2O3 showed good agreement with the predictio n from a time function of the transient and the steady-state creep associat ed with grain boundary sliding as well as an undoped one, The difference in the transient creep between Lu-doped and undoped Al2O3 can also be explain ed by the retardation of grain boundary diffusion due to the Lu3+ ions segr egation in the grain boundaries.