MECHANICAL AND CORROSION BEHAVIOR OF AL7075 (HYBRID) METAL MATRIX COMPOSITES BY TWO STEP STIR CASTING PROCESS

Abstract

THIS PAPER INVESTIGATES THE MECHANICAL PROPERTIES AND CORROSION BEHAVIOR OF METAL MATRIX COMPOSITES PREPARED USING AL7075 ALLOY AS A MATRIX, SILICON CARBIDE AND TITANIUM CARBIDE AS REINFORCEMENT PARTICLES. TWO STEP STIR CASTING PROCESS WAS USED TO FABRICATE THE COMPOSITES BY VARYING VOLUME FRACTIONS OF SILICON CARBIDE AND TITANIUM CARBIDE (0 TO 15 VOL. %). MICROSTRUCTURAL ANALYSIS, MECHANICAL AND CORROSION BEHAVIOR WERE USED TO EVALUATE THE PERFORMANCE OF THE COMPOSITES. UNIFORM DISTRIBUTION OF REINFORCEMENT PARTICLE WAS OBSERVED THROUGH OPTICAL PHOTOMICROGRAPHS. VICKERS MICRO HARDNESS TESTS WERE PERFORMED AND THE HARDNESS VALUES WERE INCREASED WITH AN INCREASE IN REIN-FORCEMENT FROM 0 TO 15 VOL. %. THE TENSILE STRENGTH OF THE 10 VOL. % OF ALUMINUM HYBRID MATRIX COMPOSITE WAS BETTER THAN THAT OF THE BASE ALLOY. IN 3.5% NACL SOLUTION, IT WAS OBSERVED THAT THE 15 VOL. % OF THE ALUMINUM HYBRID MATRIX COMPOSITE HAVE HIGHER CORROSION RE-SISTANCE IN COMPARISON THE BASE ALLOY.