Comparison of Microstructure and Tribological Behaviors of CrAlN and CrN Film Deposited by DC Magnetron Sputtering

CrAlN and CrN films were deposited on 304 stainless steel substrate by direct current magnetron sputtering. The effects of Al incorporation on the composition and microstructure for CrN film were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectrons spectroscopy (XPS), atom force microscope (AFM). The tribological behaviors of CrN and CrAlN films were characterized by wear tester against Si3N4 ball of 3 mm in diameter under different conditions and the wear profiles of film were characterized by Nanomap 500LS. The results show that the main phases of CrN film are CrN and Cr2N phase and the main phases of CrAlN film are Cr2N and CrAlN phases. The CrAlN film presents CrAlN (200) preferred orientation and CrN film presents CrN (200) preferred orientation. In terms of CrAlN film, parts of Cr atoms are taken place by Al atoms to form the CrAlN phase which is beneficial to refining grain and improving the comprehensive performance of CrAlN film. Therefore, CrAlN film exhibits a better wear-resistance performance and a lower wear rate than CrN film in all the conditions.