The R-curve behavior and thermal shock resistance for Al2O3 + ZrO2 laminated nanoceramics.

Abstract

The properties of thermal shock resistances of Al2O3 + ZrO2 monolayer and laminated ceramics are determined by the indentation method. The relationships between the R-curve, the thermal shock resistance properties and the mechanism of strengthening and toughening are also studied in this paper. The Al2O3 + ZrO2 laminated ceramics have an R-curve feature and a decrease in the sensitivity of the strength to the size of surface cracks. Indentation thermal shock test shows that the critical temperature difference of the Al2O3 + ZrO2 laminated ceramics is 400 degrees C, 150 degrees C higher than that of the monolayer ceramics. Under the condition of the surface compressive stress, the surface fracture appearance is more uneven and the fracture mechanism is different along the interface. The R-curve and thermal shock resistance properties are improved by strengthening the transformation effect resulting from the surface compressive stress.