Abstract: Aluminum alloy-ceramic particulate MMCs have been around for over one-half century employing a variety of approaches to produce the MMC. Friction applications have long been one niche market. The size, morphology, and volume loading as well as the composite processing methodology all singularly and in combination affect the friction performance. For friction applications, the surface controls the performance. Most processing methods to produce the MMC produce a cross-section that contains uniform to variations of ceramic particles through the full composite cross-section. However, for friction applications only a thin layer is needed which requires full density free of porosity that limits processing approaches to produce fully dense MMC layers. Processing has been demonstrated to apply a pore free aluminum alloy-ceramic MMC layer onto an unreinforced core. Such hybrid sandwich composites have been produced, fully friction characterized, and scaled to production quantities which have been extensively tested as automotive brakes.
Authors: James Withers and Lori Bracamonte
Keywords: Friction, Brakes, Metal Matrix Composites, Aluminum, Silicon Carbide