High-speed video photographs of lubrication breakdown in squeeze-sliding contact

Abstract

Using photographs from a high-speed video camera it was confirmed that the main part of breakdown of a lubricating film will appear at the end of the contact time for a contact simultaneously subjected to squeeze and sliding motion. This corresponds with earlier findings using totally different equipment for electric detection of the asperity contact. The present investigation used glass and steel as the lubricated surfaces, instead of steel and steel as was the case in the earlier investigation. In combination with far less stiff equipment, the new materials gave longer contact time and larger elastic deformations of the contact bodies. It was also verified that increased surface roughness, increased sliding velocity and decreased viscosity increase the risk of oil film breakdown.