Mechanical properties of electric assisted friction stir welded 2219 aluminum alloy

Abstract

The effect of 0–600 A direct current on mechanical properties of electrically assisted friction stir welded (EFSWed) joints of 6mm thick 2219 aluminum alloy were investigated. The introduction of current causes the temperature difference between the advancing side and the retreating side to become larger. Compared with the traditional friction stir welded joint, the introduction of current improved the overall hardness of the weld zones, especially the weld zones at the AS. The tensile strength of the joint of 100–400 A has improved by 2.74%–7.38%, and the tensile strength of the joint with 500A and 600A has significantly improved by 17.11%. The FSW joints failed at the nugget zone/ thermo-mechanically affected zone boundary region at the AS. The EFSW joints fractured in the nugget zone at the retreating side with the minimum hardness, and cross section of the fracture morphology is a V-shaped ductile fracture. The fracture dimples of the EFSW joint with current of 500–600 A are larger and deeper.