Surface characterization of a real-world cylinder liner subject to deposition from combustion

This paper investigates the effects of combustion product deposition using a cylinder liner taken from a C-segment passenger vehicle run for 105,000 miles. Using a novel methodology of Atomic Force Microscopy and X-ray Photoelectron Spectroscopy the pressure coefficient of boundary shear strength of asperities and the nature of the depositions along the liner is considered to predict the boundary friction of a piston ring pack. Results show that the combustion depositions create localized values of the pressure coefficient of boundary shear strength of asperities at top dead centre, mid-stroke and bottom dead centre, increasing ring pack friction by 50 N in the combustion stroke per engine cycle.