Composite friction materials based on metallic fillers: Sensitivity of μ to operating variables

Variation in μ during braking with operating variables is of major concern to the composite manufacturers, since it is composition specific. The frictional response of a multicomponent NAO friction composite is highly complex under a set of dynamically variable pressure and speeds. This paper discusses the sensitivity of friction (μ) towards braking pressure and sliding speed of selected composites based on variation in an inclusion of metallic fillers, viz. brass, copper and iron. Among metallic fillers, copper powder proved very effective in reducing μ-sensitivity to dynamic variations in pressure and speed. Regression analysis of μ values was also carried out.