Mechanical properties of infiltrated alumina-Y-TZP composites

Small Al2O3 additions (similar to 4 vol%) made to Y-TZP using an infiltration technique increased the fracture toughness and strength by similar to 15% and the amount of transgranular fracture. Ionic conductivity measurements showed decreased grain-boundary conductivity, confirming a change in the grain-boundary composition. The predominant failure origins for both the unmodified Y-TZP and the Al2O3-Y-TZP were surface flaws related to agglomerates in the original powder Finishing reduced the severity of these flaws and substantially increased the strength 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.