Lubricating properties of silica/graphene oxide composite powders

The silica/graphene oxide (GO) composites powders of different compositions were synthesized by hydrothermal method. Composites were dispersed in ethylene glycol keeping the additive's concentration constant (0.125 wt%). The lubricating properties of the dispersions were studied in steel-steel contact by pin-on-disc method. Tests were conducted at a low speed (0.008 m/s) and a high normal load of 68.9 N. Composite with 10 wt% of GO in silica matrix showed reduction of coefficient of friction in ethylene glycol by 38% and reduction of disc wear coefficient by 31% compared to pure ethylene glycol. Silica/GO composites provided lower friction and wear rate in ethylene glycol lubrication compare to pure silica and pure GO.