Investigations on GTAW and FSW of Al6061-ZrB2-Fly ash hybrid metal matrix composites

Abstract

Various hard ceramic particles, carbonaceous, organic, fibers, and other materials are used to reinforce aluminum alloys. These composites, identified as aluminum metal matrix composites possess low density, high strength, low thermal expansion, and strong structural rigidity. In this research work, a comparison of the traditional fusion welding method (GTAW) and Friction Stir Welding (FSW) in joining such composites is carried out. Suitable parameters for the welding process are estimated to join Al6061-ZrB2-fly ash composites. The mechanical or physical properties of the parent metal and weldments, such as tensile strength and hardness, are investigated. In addition, their microstructure correlations are also evaluated. It is found that the physical properties of the parent metal have improved as a result of the variations in the reinforcements. At the higher percentage of the reinforcement, the properties have deteriorated due to the excess slag accumulation. The fusion welding process yielded better mechanical properties than the solid-state welding system in the comparative analysis. This is attributed to the efficiency of the fusion welding process for joining composites of this kind. Despite the fact that the solid-state welding process produced better microstructures in the weld region, particle segregation occurred, lowering the properties. Unlike other studies, the microstructure of the fusion-welded samples here has greater integrity and less particle segregation. Grain refining has also occurred, resulting in improved mechanical properties.