DEVELOPMENT OF HIGH TEMPERATURE SIC CONTINUOUS FIBERS

THE MAIN OBJECTIVE OF THIS PROPOSED PROGRAM IS TO DEVELOP HIGH PURITY, HIGH TEMPERATURE, SMALL DIAMETER CONTINUOUS SIC FIBERS VIA A CHEMICAL VAPOR DEPOSITION (CVD) PROCESS FOR USE IN CERAMIC AND METAL MATRIX COMPOSITES WHICH WILL BE USED TO FABRICATE COMPONENTS FOR ADVANCED AIR BREATHING PROPULSION AND HIGH TEMPERATURE ENERGY CONVERSION SYSTEMS. IN PHASE I, THE FEASIBILITY OF FABRICATING A HIGH PURITY, SMALL DIAMETER CONTINUOUS SIC FIBER VIA CVD WILL BE ESTABLISHED. SMALL SAMPLES OF SIC FIBERS WILL BE FABRICATED ON CARBON AND OTHER SUBSTRATES. THE SIC FIBERS WILL BE CHARACTERIZED FOR IMPORTANT PROPERTIES SUCH AS DENSITY, HARDNESS, TENSILE STRENGTH, ELASTIC MODULUS, CHEMICAL PURITY, CRYSTALLINE STRUCTURE, AND THERMAL EXPANSION COEFFICIENT. A CONCEPTUAL DESIGN OF A CONTINUOUS SIC FIBER APPARATUS WILL BE PERFORMED. FURTHER, A HIGH POWER CO2 LASER WILL BE USED TO HEAT THE FIBERS ABOVE 1200 C TO ASSESS ANY DEGRADATION IN FIBER PROPERTIES.