Effect of Commercial Oil Additives on Wet Friction Systems

The effects of ten commercial oil additives on the static and dynamic coefficients of friction of graphitic paper and elastomeric friction materials have been investigated. Additives which function as a friction modifier, detergent, extreme pressure agent, antioxidant, viscosity index improver, or dispersant were included in the study. Using stepwise addition of the additives to the base oil in the dynamometer, the changes in static and dynamic coefficients of friction attributable to the additive were determined for a porous, graphitic paper type product and a more dense, But resilient, elastomeric friction material. Interactions of the additives in determining the frictional properties of these materials were also investigated.