Graphene coatings for tribological applications - poster
Yugal Rai
Centre for Process Innovation (CPI), National Formulation Centre, The Coxon Building, John Walker Road, NETPark, Sedgefield, County Durham, TS21 3FE, United Kingdom.

The application of graphene, graphene oxide and other forms of modified graphene as filler materials in polymers and ceramic coatings, and as additives to conventional lubricants have demonstrated a benefit in protective coatings [1]. A polymer-based coating with 5 and 10 graphene weight % were developed in CPI for the purpose of this study, along with coatings without graphene. Various dispersing methods including centrifugal mix, ultra turrex and three roll milling of graphene were evaluated. Results on steel substrates demonstrate a correlation between the roughness and the adhesion with the graphene dispersion method. Tribo-tests in unidirectional and reciprocating motion were conducted under dry conditions, these showed the presence of graphene on the wear scar for both motions through Raman spectroscopy. Inclusion of graphene within the coating resulted in lower friction for both types of motion under dry condition, where the decrease in friction has been attributed to the formation of graphene layers.

[1] Nine, M., Cole, M., Tran, D. and Losic, D. (2015). Graphene: a multipurpose material for protective coatings. Journal of Materials Chemistry A, 3(24), pp.12580-12602