Mechanism of abrasion reduction in polydisperse system with carbon nanoparticles

The research is focused on the problem of abrasive wear. The authors proposed a model based on the adsorption theory, where abrasive particles are used as transport of nanoscale additive for lubricant. Laboratory tests have been performed to determine tribotechnical, physico-chemical and rheological properties of polydisperse suspensions. It was determined that the suspensions consisting of lubricant and carbon nanotubes have high stability when pretreated by ultrasound. Rheological tests performed by rotational viscometry indicated that the insertion of carbon nanotubes slightly increases the kinematic viscosity of the lubricants. Modification of liquid lubricants with multi-walled carbon nanotubes results in wear reduction of friction surfaces by up to 10%. The combined use of an abrasive contaminant increases the efficiency of the additive by up to 35%. Carbon nanotubes provide a shielding effect and reduce the cutting effect of abrasive particles. The analysis of temperature dependences obtained in the tribological experiments allowed us to conclude that modification of lubricants with carbon nanotubes can increase thermal conductivity of compositions, which contributes to effective heat transfer from the friction zone.