Mechanical, tribological and corrosion performance of WBN composite films deposited by reactive magnetron sputtering

WBN composite films with various boron contents ranging from 25.1 at.% to 46.5 at.% were deposited by a multi-target magnetron sputtering system. The microstructure, mechanical, tribological and corrosion behavior of films were studied using XRD, SEM, FTIR, HRTEM, nano-indentation, Ball-on-disc dry sliding wear tester, Bruker 3D Profiler and compared to W2N. All the films exhibited face-centred cubic (fcc) structure W2N; bcc α-W phases appeared as the B content was 25.1 at.% and amorphous BN appeared as the B content was 31.9 at.%. The hardness and compressive stress of WBN films first increased and then decreased with increasing the B content. As the B content was 38.1 at.%, they reached the maximum values of 36.1 GPa and 2.6 GPa, respectively. The best wear resistance at room and elevated temperature was found for the film which was shown to exhibit the highest hardness and compressive stress. The corrosion resistance of the substrate which coated with W2N films or WBN films was superior to the uncoated substrate. The corrosion resistance of the substrate which coated with W2N films was improved slightly by doping some boron content.