Studies on Development and Evaluation of Asbestos-Free Friction Materials for Automotive Applications

摘要

This paper deals with the studies made on four different asbestos-free friction composites containing 2 and 4 vol.% of Kevlar pulp and 15 and 25 vol.% of glass fibre, respectively, together with suitable fillers and modifiers in appropriate quantities. The asbestos-free formulations, based on a phenolic resin matrix, were produced by the compression moulding technique. Laboratory level tests were carried out on the four composites chosen using a pin-on-disc setup and their friction, tribological and wear characteristics have been highlighted. The preliminary studies made helped identify two composites, from among four different compositions, that offered an optimum combination of properties for automobile brake pad/lining applications. Brake pads were made of 4 vol.% of Kevlar pulp and 25 vol.% of glass fibre as the reinforcement and were subjected to dynamometer testing to assess their suitability for automobile applications. The results of the first few stages of the test have only been presented and discussed in this paper. The property enhancement brought about has been correlated to composition, microstructure and the intrinsic changes occurring on the surface of the friction composites.