The tribological evaluation of graphene oxide and tungsten disulfide spray coatings during elevated temperature sliding contact of aluminum-on-steel

Abstract The high tendency of aluminum to adhere to steel has led to extensive research into the application of lubricants to reduce adhesion and friction during forming processes. The behavior of lubricants like tungsten disulfide (WS 2 ) and graphene oxide (GO) are sensitive to their deposition method. WS 2 applied through aerosol spray has been observed to increase its working temperature range. This research aims to evaluate the tribological and durability properties of WS 2 and GO (deposited as an aerosol spray coating) at temperatures between 25 °C and 450 °C, using ball-on-disc sliding tests. The spray coatings displayed low COF during sliding contact which has been attributed to the formation of transfer layers on the steel counter-faces and tribolayers on the coated Al-Mg surfaces, while their durability was observed to be related to the stability of the tribolayers. The WS 2 spray coating was noted to possess more durable tribolayers, which could be a result of the superior adhesion properties of the carbon-bonded WS 2 platelets to each other and the Al Mg substrate.