FRACTURE-TOUGHNESS OF AL2O3-PARTICLE-DISPERSED Y2O3-PARTIALLY STABILIZED ZIRCONIA

The fracture toughness of 3 mol% Y2O3-ZrO2 (3Y-PSZ) composites contain ing 10-30 vol% Al2O3 with different particle sizes was investigated. I t was found that Al2O3 dispersion of up to 30 vol% increased the fract ure toughness by 17% to 30%, and the toughness increase was more remar kable in the composite dispersed with Al2O3 particles of larger sizes. By combining the effects of the dispersion toughening and phase trans formation toughening, the toughness change in the present materials wa s theoretically predicted, which was in good agreement with the experi mental data.