Effect Of aluminum/copper as a metal filler in non-asbestos organic (NAO) brake composites materials for medium duty application

The current study investigates the feasibility of using Aluminium (Al) powder instead of Cu powder as a metal filler in NAO brake pads. To compare the performance of two fillers, a series of four brake pads containing Al powder was developed by increasing its amount from 0 to 15 wt % in steps of 5 % while keeping all other ingredients the same (phenolic resin 10%, glass fibre, rock wool aramid fibre 21%, cashew dust and vermiculate 20%, barite 22%, and alumina 2%). The physical, mechanical, and tribological properties of these pads were studied. The tribo-performance of the brake pads was assessed using a Pin-On-Disc (POD) tribometer rig (Ducom, TR-208 M1). It was discovered that when the amount of Al in the brake pads increases, almost all the attributes of the brake pads, including wear resistance, remain almost the same. Despite this, Cu-containing brake pads with 0% Al (Al0) performed somewhat better in terms of mechanical performance, whereas Al-based brake pads with 15% Al (Al15) perform nearly identically in terms of wear resistance and provide a little higher and more stable friction coefficient. In comparison to the Cu-filled pads Al0, worn surface analysis with a scanning electron microscope (SEM) indicated that Al15 had more primary and secondary plateaus, resulting in higher and more stable friction of Al-filled pad.