Effect of transverse speed on mechanical and microstructural properties of friction stir welded aluminium AA2024-T351

Among the emerging new welding technologies, friction stir welding (FSW) is used frequently for welding of high strength aluminium alloys, which are difficult to weld by conventional fusion welding techniques. In the same context, AA2024-T351 is welded using FSW technique with square shaped tool pin profile. FSW of AA2024-T351 are done on different transverse speed to understand the influence of transverse speed on microstructural characteristics and mechanical properties. The microstructural characterisation is done using optical microscope to understand the grain size and grain morphology. The mechanical properties are obtained by hardness and impact test. From the obtained microstructure, it is found that the grain size is decreasing as transverse speed increases. The impact strength also reduced as a function of transverse speed, whereas maximum hardness is observed on 100 mm/min transverse speed.