Effect Of Ageing On Mechanical Behavior Al-alb2metal Matrix Composites

In the present era MMC's prepared with aluminum alloys are used in several applications. Synthesis of aluminum composite material by insitu technique becomes one of the popular methods because of its several advantages over the conventional methods. In this present paper, Al-xAlB2(x= 1, 3 and 5 wt.%) insitu composite were prepared and fabricated via exothermic chemical reaction between molten aluminium alloy and mixed halide salts KBF4andcryolyteNa3AlF6at a temperature of 8000C -8500C by using vortex method. The as cast matrix alloy and inistu composites specimens have been subjected to solutionizing treatment at a temperature of 5350C for an hour and followed by water quenching. The quenched specimens were subjected to artificial ageing at a temperature of 1750C for an about 10 hours. The composite were subjected to microstructure analysis and the result revealed that fine and clean AlB2particles distributed uniformly with good interfacial bonding and dislocations was observed throughout the matrix by using SEM/EDS. Most of the AlB2particulates exhibits with different morphologies including Spherical, cylindrical and hexagonal shapes were found near the grain boundaries. The composites were evaluated for mechanical tests like hardness, tensile and compression by the ASTM standards by using hardness and UTM machine. The compositesenhanced the hardnessand mechanical properties with increasesin the weight fraction of AlB2particles but ductility of the composite is decreases