Impact of Si addition on oxidation resistance of Zr–Si–N nanocomposite films

Abstract

Incorporating Si element into nitride films is known to enhance mechanical properties and oxidation resistance. Here, we reported the nanocomposite films of Zr–Si–N deposited using a hybrid deposited system combining rf magnetron sputtering from a Si3N4 target with dc magnetron sputtering from Zr target. Microstructure and oxidation resistance of Zr–Si–N nanocomposite films with 0–20.9 at.% Si content were investigated. The results indicated that the binary Zr–N film exhibits a typical columnar structure and the Zr–Si–N films become denser as the elevated Si content. The cross-section of film transforms to a dense and glassy structure when increasing the Si concentrations. The oxide scales of the Zr–Si–N films consist of ZrO2 nanograins and amorphous SiNx tissue. The introduction of the Si element significantly improves the oxidation resistance of the Zr–Si–N films due to the amorphous SiNx tissue phase suppresses both the inward diffusion of the oxygen and cracking in oxide scale caused by the phase transition from t-ZrO2 to m-ZrO2.