Enhanced mechanical and tribological performance of epoxy nanocomposite coating by non-covalent bonded h-BN nanosheets/graphene oxide

Developing high-performance of organic solid lubricating coating is of great significance for extending the life of the moving systems/parts. Herein, the non-covalently modified h-BN nanosheets by graphene oxide (BNNSs/GO) were elaborately constructed to enhance the mechanical, friction and wear properties of epoxy nanocomposite coating. The microstructure feature and chemical composition of BNNSs/GO were determined by various spectroscopic techniques. The tribological performance of nanocomposite coatings were tested using ball-on-disc friction tester, and 440C stainless-steel ball with diameter of 8 mm was used as the counterface material. The GO nanosheets acted an active platform for BNNSs, which improved the dispersion of BNNSs and interface interaction with epoxy. The anchoring BNNSs could break the strong π-π, and van der Walls forces among GO nanosheets. The thickness of epoxy nanocomposite coatings was about 60 μm. And the epoxy-1.0 wt%BNNSs/GO demonstrated much higher hardness and elastic modulus than epoxy, increased by 112.62 % and 53.37 %, respectively. The coefficient of friction (COF) and wear rate of epoxy-1.0 wt%BNNSs/GO were the lowest, with a reduction of 89.7 % and 97.5 %, respectively. The synergistic lubricating mechanism of epoxy-BNNSs/GO coating was proposed, which could provide a new light on the design of high antifriction and wear resistance of organic nanocomposite coating.