fabrication of al/graphite/al2o3 surface hybrid nano composite by friction stir processing and investigating the wear and microstructural properties of the composite

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to implement powder mixture into the aluminum alloy matrix. microstructural properties were investigated by means of optical microscopy and scanning electron microscopy (sem). it was found that reinforcement particle mixture was distributed uniformly in nugget zone. wear resistance of composite was measured by dry sliding wear test. as a result, hybrid composite revealed significant reduction in wear rate in comparison with al/al2o3 composite produced by friction stir processing. worn surface of the wear test samples were examined by sem in order to determine wear mechanism.