Roughness-dependent tribological characteristics of water-based GO suspensions with ZrO2 and TiO2 nanoparticles as additives

Hybrid nanosuspensions were synthesised through ultrasonically dispersing ZrO2 or TiO2 nanoparticles into graphene oxide (GO) nanosheet solutions for water-based lubrication. The effect of contact pair roughness on the tribological behaviours of the ZrO2/GO and TiO2/GO hybrid nanosuspensions were investigated using a blockon-ring testing approach. With a relatively smooth ring, the use of the nanosuspensions could reduce abrasive wear, and hence improve worn surface quality, owing to the relieved asperity ploughing. With a ring of moderate roughness, the use of the nanosuspensions suppressed the occurrence of adhesive wear through relieving the effect of asperity contact. With a relatively rough ring, the nanosuspensions generated a deposited layer of hybrid nanoparticles at the contact area that can prevent surface asperities from direct contact, thus leading to lower adhesive wear and friction.

Automated summary

The study found that the use of hybrid nanosuspensions can reduce wear, improve worn surface quality, suppress adhesive wear, and prevent direct contact-induced friction for contact pairs with different roughness levels.