Tri-dissimilar T-joints in Aluminium Alloys by FSW: microstructural and mechanical characterisation
By Neves Manuel (University of Coimbra), José Costa (University of Coimbra), Altino Loureiro (University of Coimbra)

The aim of this research is to investigate the influence of the welding speed and base material properties on the morphology and mechanical behaviour of tri-dissimilar aluminium T joints produced by FSW.

The base materials were the AA2017-T4, AA5083-H111 and AA6082-T6 alloys. The AA6082-T6 was the stringer and the other alloys were the skin plates. The effect of positioning of the skin alloys in advancing/retreating sides was analysed. The mechanical properties welds was assessed by micro-hardness, tensile and fatigue testing.

The positioning of the skin plates influenced the morphology and mechanical behaviour of welds. The welding speed was found to influence the defects formation and fatigue strength of welds.