Influences of post weld heat treatment on tensile strength and microstructure characteristics of friction stir welded butt joints of AA2014-T 6 aluminum alloy

ABSTRACT Friction stir welded (FSW) joints of aluminum alloys exhibited a hardness drop in both the advancing side (AS) and retreating side (RS) of thermo-mechanically affected zone (TMAZ) due to thermal cycle involved in the FSW process. In this investigation, an attempt has been made to overcome this problem by post weld heat treatment (PWHT) methods. Friction stir welded butt joints of Al-Cu (AA2014-T6) alloy were PWHT by two methods such as simple artificial aging (AA) and solution treatment followed by artificial aging (STA). Of these two treatments, STA was found to be more beneficial than simple aging treatment to improve the tensile properties of the FSW joints of AA2014 aluminum alloy.