Development of AlB2 particles using inorganic halide salts and mechanical characterization of AlB2 reinforced AA6061 MMC’s

Abstract

Insitu AA6061/AlB2 composites with different weight percent (0, 1, 3 & 5) AlB2 particles were fabricated through liquid metallurgy route involving a chemical reaction of exothermic nature between molten AA6061 alloy and an inorganic halide salt of potassium tetra fluoro borate (KBF4) at reaction temperatures from 800° to 850 °C using stir casting route. The fabricated composites were subjected to micro structural characterization using SEM and XRD. Microstructural studies revealed that the formation of insitu AlB2 particles decreased the size of the grain in Aluminium rich phase. Further examination shows uniform scattering of in-situ particles throughout the matrix. An attempt is made to find out the shape of the insitu particles. The processed composites were further analysed to get their mechanical characterization like tensile, hardness, compression and density properties. As the proportion of reinforcement particulates increased, the composites hardness, yield strength, ultimate tensile and compression strength of the developed composites were found to increase proportionally, however there is an abatement in ductility with increments in reinforcement content.