MECHANICAL-PROPERTIES OF INFILTRATED ALUMINA-Y-TZP COMPOSITES

Small Al2O3 additions (similar to 4 vol%) made to Y-TZP using an infil tration technique increased the fracture toughness and strength by sim ilar to 15% and the amount of transgranular fracture. Ionic conductivi ty measurements showed decreased grain-boundary conductivity, confirmi ng a change in the grain-boundary composition. The predominant failure origins for both the unmodified Y-TZP and the Al2O3-Y-TZP were surfac e flaws related to agglomerates in the original powder Finishing reduc ed the severity of these flaws and substantially increased the strengt h of both materials (>50%). The infiltration approach introduced a new flaw population in some specimens; however, this problem was overcome by a simple processing modification.