Tribological performance of AlCrN coating sliding against Si-based ceramic balls in ambient air and seawater conditions

AlCrN coatings were deposited on 316L stainless steel substrates by the multi-arc plating technique. Composition, morphology, phase and hardness of the AlCrN coatings were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and nano-indenter tester. The tribological performance of AlCrN coatings sliding against the Si₃N₄ and SiC ceramic balls under ambient air and seawater conditions were investigated by using a tribometer (Rtec). The results show that the coefficient of friction and wear rates of AlCrN/SiC are far lower than that of AlCrN/Si₃N₄ in both environments. The tribochemical product (SiO₂) occurs on the wear area and being acted as a lubricant. Dimples on the surface of SiC are in favor of keeping the tribological film in the wear track and relieving the abrasive wear. In comparison with Si₃N₄, the AlCrN coating sliding against SiC ceramic exhibits more excellent tribological properties.