Development and Tribological Characterisation of Eco-Friendly Brake Pad Composites Using Coconut Shell Powder as Natural Filler

Abstract

Conventional automotive brake pad friction materials commonly contain asbestos and other mineral fibres that pose health and environmental hazards during manufacturing, use, and disposal. This paper presents the development and experimental characterisation of an eco-friendly brake pad composite using coconut shell powder as a natural reinforcing filler, replacing a portion of conventional aluminium oxide and graphite filler material. Five brake pad specimens (B1 to B5) were fabricated using the compression moulding process with varying coconut shell powder content from 0 to 40 weight percent, while maintaining constant resin binder and brass fibre content. Physical properties (density, hardness), mechanical properties (compressive strength), and tribological properties (friction coefficient and wear rate) were evaluated following relevant ASTM and SAE test standards. Results show that specimen B3, containing 20 weight percent coconut shell powder, provides the best overall balance of properties, achieving a friction coefficient of 0.441 (within the desirable automotive brake pad range of 0.35–0.45) and the lowest wear rate among all specimens tested (6.42 × 10⁻⁵ mm³/Nm), while reducing material density by 9.9 percent compared to the conventional control specimen. High-temperature friction testing up to 400°C confirms stable friction performance, with the coconut shell filled composite maintaining higher friction coefficient than the control specimen across the full temperature range tested.

Cite as:

Kumbhar Aditi. (2026). Development and Tribological Characterisation of Eco-Friendly Brake Pad Composites Using Coconut Shell Powder as Natural Filler. Recent Innovations in Material Engineering, 2(2), 18–23. https://doi.org/10.5281/zenodo.21850817