CERAMIC REINFORCEMENT FOR METAL MATRIX COMPOSITES DEVELOPMENT

RECENT DEVELOPMENTS IN THE AUTOMOTIVE INDUSTRY HAVE DEMONSTRATED THAT DISCONTINUOUS CERAMIC FIBER REINFORCEMENT CAN BE INCORPORATED IN A METAL MATRIX BY THE RELATIVELY SIMPLE AND INEXPENSIVE PROCESS OF SQUEEZE CASTING. THE OBJECTIVE OF THIS PROGRAM IS TO UPGRADE THIS TECHNOLOGY TO PRODUCE MATERIALS WHICH ARE FULLY, RATHER THAN SELECTIVELY, REINFORCED BY UP TO 20 VOLUME PERCENT DISCONTINUOUS FIBERS. HIGH PRESSURE CASTING APPARATUS WILL BE UTILIZED TO INCORPORATE OXIDE, GRAPHITE, AND SILICON CARBIDE FIBERS, INITIALLY PRESENT AS FIBER PERFORMS OR MATS, IN AN ALUMINUM ALLOY MATRIX. FLOW AND INFILTRATION CHARACTERISTICS OF THE MOLTEN MATRIX WILL BE STUDIED, AND THE RESULTANT COMPOSITE MATERIALS WILL BE CHARACTERIZED WITH RESPECT TO AMBIENT AND ELEVATED TEMPERATURE MECHANICAL PROPERTIES. SUITABILITY OF THE MATERIALS FOR OTHER THAN STRENGTH-RELATED APPLICATIONS WILL BE ASSESSED.