Thermal shock resistance of dense zirconia matrix composites evaluated by indentation techniques

The thermal shock behavior of 3Y-TZP/LaPO4 composites containing 0, 15, 30 vol.% LaPO4 was evaluated with an indentation-quench method based on propagation of Vickers cracks. The effect of LaPO4 particle size on the thermal shock behavior of 3Y-TZP/LaPO4 composites was investigated preliminarily. Results showed that the composite containing 15 vol.% 900 °C sintered LaPO4 exhibited better resistance to crack propagation and thermal shock under water quenching condition. Larger grain size or higher content of LaPO4 would deteriorate the thermal shock resistance of 3Y-TZP/LaPO4 composites. The calculation of thermal shock resistance parameter Rst for the composites gives a possible explanation for the difference in thermal shock behavior.