Tribological performances of CrAlN coating coupled with different ceramics in seawater

This paper attempts to present a comparative study of tribological performances of chromium aluminum nitride (CrAlN) coating coupled with Si3N4, SiC, WC, Al2O3 and ZrO2 balls in air and seawater. The comparison results show that the tribological performance of different tribopairs is determined by the property of ceramics. Seawater plays an important role in reducing the coefficient of friction (COF) by forming tribochemical films and developing a hydrodynamic lubrication regime. The wear rates of CrAlN/SiC in air and seawater are much lower than that of the combination of CAIN and other tribopairs because of the integrated effect of tribochemical film and micro-dimples on SiC ball. It is therefore apparent that CrAlN/SiC has the smallest COF and lowest wear rate in both air and seawater