IN SITU ALUMINIUM COMPOSITES

Abstract

Preparing aluminum matrix composites (AMCs) using in situ method results in many desirable benefits. Here it is focused on preparing AA6061/ (0%, 3% by simple casting method, 3% with ultrasonication, 6%by simple casting method, 6% with ultrasonication ZrB2 AMCs by Al–K2ZrF6–KBF4 reaction system. The inorganic salts were added to molten aluminium alloy at an elevated temperature of 850OC. The prepared AMCs were studied by applying conventional microcopy and advanced characterization techniques. XRD peaks confirmed the successful synthesize of ZrB2 particles. No other phases such as Al3Zr and AlB2 were detected in appreciable quantity. There was a refinement of grains in the composite due to ZrB2 particles. Two kind of distribution was observed in the micrographs. Particle clusters were observed with increased weight fraction of particles. ZrB2 particles were observed to be sub–micron and nano level in size and characterized by proper interfacial bonding with the aluminum matrix. The mechanical properties were improved remarkably by the incorporation of ZrB2 particles and the possible strengthening mechanisms were discussed