INJECTION MOLDING OF METAL MATRIX COMPOSITES

METAL MATRIX COMPOSITES (MMCS) REPRESENT AN EMERGING CLASS OF STRUCTURAL MATERIALS WITH POTENTIAL APPLICATIONS RANGING FROM DIMENSIONALLY STABLE SPACE STRUCTURED COMPONENTS TO HIGH THERMAL CONDUCTIVITY PACKAGES FOR HYBRID MICROELECTRONICS. USE OF MMCS IN COMMERCIAL APPLICATIONS HAS BEEN LIMITED TO DATE BECAUSE OF HIGH MATERIAL COSTS AND EXTREMELY HIGH MANUFACTURING COSTS (BOTH MATERIAL FABRICATION AND FINISHING). FABRICATION OF METAL MATRIX COMPOSITES IS USUALLY ACCOMPLISHED VIA SOLID STATE (DIFFUSION BONDING) OR LIQUID INFILTRATION (E.G. CASTING) TECHNIQUES. THE OBJECTIVE OF THE PROPOSED RESEARCH IS TO DEVELOP A NOVEL MANUFACTURING METHOD FORLOW COST NET SHAPE PRODUCTION OF COMPLEX COMPONENTS. THE APPROACH INVOLVES BLENDING OF TWO ALLOY POWDERS WITH A CERAMIC REINFORCEMENT MIXED TOGETHER USING A HIGHLY VOLATILE ORGANIC BINDER. DURING CONSOLIDATION, THE BINDER IS DRIVEN OFF AND THE LOW MELTING MATRIX POWDER TURNS TO LIQUID AND ACTS AS A WETTING AGENT TO IMPROVE BONDING BETWEEN THE MATRIX AND REINFORCEMENT. THE FINAL COMPOSITE IS ANTICIPATED TO HAVE PROPERTIES EQUIVALENT TO CONVENTIONALLY PROCESSED MATERIALS AT MUCH LOWER PER UNIT COST.