The Mechanism of High Thermal Shock Resistance of Nanostructured Ceramic Coatings

The nanostructured and the conventional Z r O ₂ coating samples were thermal shocked at a series of temperatures. The elastic modulus and the hardness of two kinds of coatings were investigated by the nanoindentation tests. The results show that the corresponding mechanical properties of the conventional coatings increase monotonically with increasing temperature difference of the thermal shock. While the modulus and the hardness of the nanostructured coatings fluctuate slightly with increasing thermal shock temperature difference. Furthermore, the interface energy release model of the thermal shock strain energy was proposed for the nanostructured coatings. The theoretical prediction agrees with the experimental result.