Assessment of Wear Characteristics of Paper-Based Wet Friction Materials

A wet clutch synchronizes the speed and transmits power from an engine or motor to a drive train by mechanical coupling between a friction disk and a separate disk. The performance of a wet clutch may be significantly dependent on the friction and wear characteristics of paper-based friction materials. In this work, the wear characteristics of paper-based friction materials were experimentally investigated using a pin on reciprocating plate tribo-tester. In particular, the wear characteristics of paper-based friction materials with and without carbon fibers were assessed in a boundary lubrication state with respect to normal force and sliding speed. The tests found that the wear rate of paper-based friction materials increased with increasing normal force and sliding speed. The wear rates were found to vary in the range of 10(-6)-10(-4) mm(3)/(N center dot cycle). In addition, paper-based friction material with carbon fiber exhibited relatively larger friction and wear characteristics than those without carbon fibers. It was observed that the carbon fibers were broken due to the sliding contact, which may have contributed to the wear progression. The outcomes of this work may be helpful in gaining a better understanding of the tribological characteristics of paper-based friction materials in order to enhance the lifetimes of wet clutches.