High-Temperature Oxidation Resistance of CrMoN Films

The CrMoN film is deposited on the surface of M2 tool steel using the closed-field unbalanced magnetron sputtering technology. We measured the surface morphology, composition, phase structure, hardness and film/base bonding strength of CrMoN film using a scanning electron microscope, x-ray diffractometer, nano-indenter and scratch tester after oxidation at room temperature, 500, 600, and 700 °C for 1 h. The results of this study demonstrated that the crystal structure and mechanical property of CrMoN film at room temperature are maintained after oxidation at 500 °C for 1 h. In addition, with the increase in oxidation temperature, there is an increase in the evaporation of MoO₃ on the film surface and the oxidation degree of the film along with the appearance of fine pores. Moreover, the mechanical property and film/base bonding strength of CrMoN film significantly decrease after oxidization at 700 °C for 1 h.