Hexagonal boron nitride nanosheets eco-friendly dispersed in pure water for lubrication in fretting contacts between steel pairs

Abstract

The lubricating effect of h-BN nanosheets, dispersed in pure water without the use of any chemicals, was investigated under fretting contacts. The resistance against oxidation of sliding pairs was also considered using AISI 52100 and AISI 304 steel pairs separately, given that oxidation is inevitable on steel surfaces. In the partial slip regime, effects of the type of lubricant and oxidation on wear and friction were insignificant. In the mixed slip regime, the mending effect of h-BN counteracted the oxidation of sliding surfaces, resulting in mild wear. In the gross slip regime, the mending effect collapsed due to oxide debris, resulting in severe wear. Moreover, the results showed that the presence of h-BN nanosheets influenced the transition of fretting regimes. These findings suggest that aqueous-dispersed h-BN nanosheets can be an effective eco-friendly lubricant additive, particularly when fretting conditions enable a stable mending effect and sliding surfaces exhibit high corrosion resistance.