Tribological and acoustic evaluation of non-asbestos copper-free automotive brake pads with olefin elastomers

Purpose This study aims to develop and evaluate copper-free brake pads using an olefin-based elastomer as an alternative to conventional nitrile butadiene rubber (NBR)-based formulations. This research also benchmarks the newly developed pad against the commercial brake pad to determine its viability in real-world applications. Design/methodology/approach Brake pads were fabricated using an olefin-based elastomer and compared with NBR-based and commercial pads. Following industrial protocols, all samples were tested for physical, chemical, mechanical and acoustic properties. Tribological behavior was assessed using Chase testing in compliance with SAE J661, and damping behavior was measured using an impedance tube. A scanning electron microscope (SEM) was used to examine the worn surface. Findings The olefin-based elastomer brake pads demonstrated superior fade-recovery performance and wear resistance compared to other brake pads. The olefin-based elastomer brake pads exhibited a higher sound absorption coefficient, indicating improved acoustic damping. SEM analysis confirmed better contact plateaus, which improve tribological performance. Research limitations/implications The quantitative environmental assessments, including particulate emissions, airborne wear debris and life-cycle analysis, were not performed in this study and should be addressed in future work. Originality/value This work introduces an olefin-based elastomer as a copper-free alternative to conventional NBR in brake friction materials. This study provides a comprehensive performance benchmark against commercial pads, highlighting the potential of elastomer-based brake pad formulations for next-generation silent automotive braking systems.