Friction and Wear of Duralcan Reinforced Aluminum Composites in Automotive Braking Systems

Duralcan reinforced aluminum composites (hereafter referred to as aluminum composites) include foundry composites which typically consist of 20 volume % silicon carbide in an aluminum-silicon casting alloy matrix. Addition of the silicon carbide leads to a combination of properties that are not available in unreinforced aluminum alloys, e.g. high specific stiffness, and improved friction and wear behavior. These properties combined with their low density make these materials attractive as substitutes for cast iron in brake rotors in order to reduce the unsprung weight of an automobile.

The objective of this study was to determine the friction and wear performance of aluminum composites relevant to automotive braking systems. Testing consisted of sliding the aluminum composites against brake pads materials (friction materials). The aluminum composites studied encompassed changes in the base alloy, the volume fraction of reinforcement, and the reinforcement particle size. Friction vs. temperature behavior was determined at two different pressures, failure temperatures were determined, and wear rates were estimated.