Studies on Mechanical and Wear Characteristics of Friction Stir Welded AA6061 B4C Composites

Abstract

Aluminum Matrix Composites (AMCs) play a crucial role in industries such as aviation, newlineautomotive, and marine due to their exceptional mechanical properties. This study focuses newlineon AA6061 as the matrix material, chosen for its formability and customizable strength newlinethrough heat treatment, reinforced with B4C, a material known for extreme hardness and newlineunique properties such as high neutron absorption capability and thermal conductivity. newlineThe stir casting process is employed to produce B4C-reinforced AMCs with varying newlineweight percentages (0% to 12%). B4C particles of 90and#956;m are selected to optimize newlinedispersion rates. The study aims to explore the impact of B4C reinforcement on the newlinemechanical properties of AA6061-based composites. Friction Stir Welding (FSW) is newlineutilized as a solid-state joining process to weld the optimized composites. FSW offers newlineadvantages over traditional welding methods, with rotating speed, welding speed, and tool newlinepin profile identified as key parameters influencing the weldment. The absence of issues newlinelike solidification cracking and porosity, common in traditional welding, makes FSW an newlineappealing technique for AMCs. The Taguchi technique was employed to optimize the newlineprocess parameters in this study newlineThis thesis investigates the fabrication and optimization of AA6061/B4C composite panels newlinethrough the stir casting method and subsequent Friction Stir Welding (FSW) process. B4C newlinereinforcement percentages ranging from 0% to 12% were employed in conjunction with newlineAA6061 as the matrix material. Microstructural analyses, utilizing optical microscopy newline(OM) and scanning electron microscopy (SEM), confirm uniform dispersion of newlinereinforcement particles within the matrix. Mechanical properties, including ultimate newlinetensile strength (UTS) and hardness, exhibited enhancement up to 10% reinforcement, newlinebeyond which a decline was observed. Wear resistance showed improvement with newlineincreased reinforcement up to 10%, as evidenced by a decreased wear rate. Fractography newlineanalysis revealed a reduction in dimple density on fracture surfac