Improving the tribological characteristics of piston ring assembly in automotive engines using Al2O3 and TiO2 nanomaterials as nano-lubricant additives

To minimize the frictional power losses in automotive engines, it is imperative to improve the tribological characteristics of the piston ring assembly. This study examined the tribological behavior of the piston ring assembly using nanoparticles as nano-lubricant additives. The average size of Al2O3 and TiO2 nanoparticles were 8-12 nm and 10 nm, respectively. The nanoparticles were suspended using oleic acid in four different concentrations in the engine oil (0.05, 0.1, 0.25 and 0.5 wt%). The tribological behavior of nano-lubricants was evaluated using a tribometer under different operating conditions to mimic the ring/liner interface. The results showed a decrease in the friction coefficient, power losses and wear. The study provides insights into how nano-lubricant additives could contribute towards energy saving and improved fuel economy in automotive engines. (C) 2016 Elsevier Ltd. All rights reserved.