The effect of colemanite on the friction performance of automotive brake friction materials

Purpose - The purpose of this paper is to investigate use of colemanite (C) upon friction and wear performance of automotive brake lining. Brake lining production with the boron product colemanite addition and braking characterization investigated for development of non-asbestos organic (NAO) brake lining because of negative effects on human health and environmental hazard of asbestos containing linings. During the braking, brake lining is warmed up extremely due to friction, and the high temperature causes to decreasing of breaking performance. Colemanite has high melting temperature, and this makes this material valuable for brake lining. Design/methodology/approach - This study investigated the effect of colemanite (C) upon friction and wear performance of automotive brake lining. Based on a simple experimental formulation, different amounts of boron product colemanite were used and then evaluated using a friction assessment and screening test. In these specimens, half of the samples (shown with H indices) were heat treated in 4 h at 180 degrees C temperature. Friction coefficient, wear rate and scanning electron microscope for friction surfaces were used to assess the performance of these samples. Findings - The results of test showed that colemanite can substantially improve properties of friction materials. The friction coefficient of friction materials modified with colemanite varies steadily with the change of temperature, and the wearing rate of friction materials is relatively low by using colemanite. Heat treatment-applied samples (CH) have provided a higher and stable friction coefficient. These results indicate that colemanite has ideal application effect in various friction materials. Originality/value - This paper fulfils an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials. Parallel results have been presented between previously reported and present study, in view of brake characteristics and wear resistance. Use of the lower cost and productive organic sources of material are the main improvement of the present study.