Recommendations for h-BN loading and service temperature to achieve low friction coefficient and wear rate for thermal-sprayed PEEK coatings

This work investigated the friction and wear characteristics of poly(ether-ether-ketone) (PEEK) with and without addition of hexagonal boron nitride (h-BN), which was prepared by coating PEEK on carbon steel substrate via flame spray coating technique. The coatings were then tested at different temperatures (30, 100, 200 and 300 °C) by ball-on-disc sliding wear test; 100 and 200 °C were found to be suitable service temperatures to obtain low friction and wear rate for PEEK coatings. No chemical or structural changes of PEEK were observed at the temperature range used in this work. The results indicated that h-BN could be used as a wear and friction reducer for PEEK coatings under optimum loading and service temperature. The loading of h-BN at 2 wt% was sufficient for improving the wear resistance, with reduced friction coefficients. The testing temperature exhibited a more pronounced effect on the friction and wear characteristics of PEEK coatings as compared to the effect of h-BN addition.