Performance improvement of AA6061-T651 friction stir butt-weldment using particulate addition strategy

Abstract

The joint quality performance of AA6061-T651 friction stir weldments had been investigated in this study through addition of pulverized waste glass (PWG), palm kernel shell ash (PKSA) and synthetic silicon carbide (SSC) with a bid to enhancing some selected mechanical properties. Optimized processing parameters which include 1120 rpm rotational speed, 40 mm/min traverse speed, 1.5o tilt angle) and optimum reinforcement strategy (parallel hole) established from a preliminary investigation were utilized for the friction stir welding. The mechanical properties such as the tensile strength, hardness and impact energy were then further investigated. The results showed that the mechanical properties of all the reinforced welded joints improved significantly than the unreinforced joint having a relatively reduced joint performance of 132 MPa tensile strength, hardness of 45.3 HRB and impact energy of 39.4 J. The PWG-reinforced friction stir welded joint performed optimally at a tensile strength of 212.7 MPa, 72 HRB hardness and 54.5 J impact energy followed by the SSC-reinforced joint which exhibited 173.7 MPa tensile strength, 54.8 HRB hardness and impact energy of 41.7 J. Hence, 80%, 59% and 38% joint performance was exhibited through tensile strength, hardness and impact energy of PWG-reinforced friction stir weldments of AA6061-T651 against the unreinforced weldments.