High Temperature Oxidation Resistance of CN_x Thin Films Prepared by Reactive Magnetron Sputtering

CNx thin films were deposited on high speed steel (HSS) substrates by reactive magnetron sputtering (RMS), and nitrogen content in the thin films was adjusted by changing the flow ratio of N2 to Ar. The structure of the film and its high temperature oxidation resistance at 300, 400, 500, 600 ℃ was studied by XRD, HR-TEM, SEM and FTIR. The results indicate that the CNx thin films had good oxidation resistance at below 400 ℃, and oxidation annealing temperature of 500 ℃ led to serious oxidation or decomposition. Higher nitrogen content was helpful to high temperature oxidation resistance of the CNx thin films.