NOVEL LOW-COST 3-D CONTINUOUSLY REINFORCED METAL MATRIX COMPOSITES

RESEARCHERS ARE INVESTIGATING AN INNOVATIVE NEW CLASS OF MATERIALS WHICH PROVIDE DRAMATICALLY INCREASED STRENGTH, MODULUS, AND WEAR RESISTANCE WHILE MAINTAINING MECHANICAL PROPERTIES TO HIGH TEMPERATURE. THE CONCEPT UTILIZES CERAMIC FOAMS, FABRICATED BY CHEMICAL VAPOR DEPOSITION (CVD) AS HIGH-STRENGTH INTERCONNECTED THREE-DIMENSIONAL CONTINUOUS REINFORCEMENTS FOR METAL MATRIX COMPOSITES (MMCS). THE DEVELOPMENT OF THIS MATERIAL PROVIDES A LOW-COST COMPOSITE CONSISTING OF INTERPENETRATING, CONTINUOUS METAL AND CERAMIC PHASES, TAKING FULL ADVANTAGE OF THE DESIRABLE PROPERTIES OF EACH PHASE WHILE ELIMINATING THE INHERENT DRAWBACKS OF EACH PHASE, SUCH AS LOW TEMPERATURE BRITTLENESS IN CERAMICS AND HIGH TEMPERATURE CREEP AND WEAR IN METALS. THE INVESTIGATION COVERS THE MODELING, FABRICATION, CHARACTERIZATION, AND TESTING OF CERAMIC FOAM-REINFORCED ALUMINUM-BASED METAL MATRICES AND PROVIDES THE GROUNDWORK FOR FURTHER INVESTIGATION AND DEVELOPMENT. THE EFFECT OF MATERIAL COMPOSITIONS, REINFORCEMENT STRUCTURE AND VOLUME FRACTION, AND PROCESSING (MELT INFILTRATION) CONDITIONS ON THE MICROSTRUCTURE AND FLEXURE, TENSILE, AND IMPACT PROPERTIES OF THESE UNIQUE COMPOSITES IS BEING INVESTIGATED. LIMITED DESIGN INFORMATION, SUCH AS PHYSICAL PROPERTIES, MECHANICAL PROPERTIES (STRENGTH AND MODULUS), AND THERMAL FATIGUE AND THERMAL SHOCK RESISTANCE, WILL BE GENERATED AS WELL.