Varying Cu and Zn composition in brass and its effect on the fade and recovery behavior of the phenolic‐based friction composites

Abstract Brass as a functional filler in the formulation of brake friction composites helps to improve the thermal conductivity, tribo‐load bearing ability, fade, recovery and wear resistance of the brake pads. The commercial brass alloy has 70 wt% copper and 30 wt% zinc. In this work, the tribological performance of the brass powders with 60 wt% Cu +40 wt% Zn and 80 wt% Cu +20 wt% Zn having similar morphology with the commercial brass was evaluated. The commercial and the two modified versions of brass filler were introduced in the formulation. Totally nine phenolic brake composite were formulated and fabricated by varying the brass filler types and their composition (6, 8 and 10 wt%) in the brake formulations. The tribological performance of the developed brake pads was studied using a chase‐type friction tester following IS 2742 test standard. The worn surface of the tested samples was studied using scanning electron microscopy and energy‐dispersive X‐ray spectroscopy. The tribological performance of the developed samples shows a nonlinear behavior concerning the variation in the composition. Therefore, statistical evaluation techniques such as hybrid analytical hierarchy process coupled with extension evaluation method (AHP‐EEM) and analytical hierarchy process coupled with Preference Selection Index (AHP‐PSI) were used to rank the developed samples based on the multiple tribological performance parameters. Based on the evaluation process the brake composite's composition with 8 wt% brass containing 70 wt% Cu and 30 wt% Zn has given the best overall performance.