A study on microstructural effect and mechanical behaviour of Al6061–5%SiC–TiB 2 particulates reinforced hybrid metal matrix composites

In this present work, an attempt is made to prepare Al6061–5%SiC–TiB₂ hybrid composites using stir casting process by considering optimal process parameters such as stirring temperature, stirring speed, stirring time, preheating temperature, grain size and wt% of particulate reinforcement and examine their metallurgical effect and mechanical behaviour. The metal composite samples were prepared using stir casting process in which the amount of reinforcement of 5%SiC is kept constant, and second reinforcement of TiB₂ is varied by its weight fraction of 2, 4, 6, 8 and 10%. The prepared dual particulates reinforced hybrid composites are characterised, and their microstructural, mechanical properties and fractograpy were evaluated as per the standards. Strong interfacial bonding between matrix and reinforcements which are the significance of improved wettability is due to Potassium Hexafluorotitanate salt addition, and preheating of particles of SiC at 800℃ and TiB₂ at 250℃ is made before adding into the melt. The results revealed that the increase in addition of TiB₂ increases the tensile strength, flexural strength, impact strength and hardness by decreasing their weight density, and also the influence of SiC increases the hardness of the material of newly developed composite. Also, fracture morphology of tensile failure has been studied to examine micro-mechanisms of failure, and the mode of failure of the composites was found to be ductile.