A complex interdependence of dispersant in nano-suspensions with varying amount of graphite particles on its stability and tribological performance

摘要

In the present work, series of nano-oils with and without polyisobutylene succinimide (PIBSI-1 wt%) dispersant was prepared with 55 nm graphite nano-particles (NPs) (1, 2, 3 and 4 wt%) to highlight the role of dispersant and concentration of NPs on controlling tribological performance and stability of nano-oils. It was concluded that dispersant proved beneficial for the stability of nano-oils (up to 50 days). NPs proved significantly effective to enhance the anti-wear (AW) performance by 60% and maximum improvement was recorded for 3 wt% NPs. Extreme-pressure (EP) performance was also enhanced by 80%. Atomic force microscopy (AFM) on worn ball surfaces showed lowest roughness and highest bearing area in case of most performing oil with dispersant and 3 wt% NPs.