Parametric Optimization of Aluminium Alloy 1100 Friction Stir Welding Using Adapted Vertical Milling Machine

Abstract

Friction stir welding is now increasingly being applied to joining aluminum alloys and other non-ferrous metals because the process has been established to be more suitable for joining soft metals. Compared with the facilities required for fusion welding, procuring friction stir welding machine is capital intensive and its utilization in the underdeveloped nations is very scanty. In this work, some experimental works were done so as determine the optimized process parameters for friction stir welding of aluminium alloys using an adapted vertical milling machine. The focus is to optimize the friction stir welding of AA1100 using an adapted vertical milling machine so as to obtain high quality weldments in terms of hardness and tensile strength. Friction stir welding of AA1100 was performed within a process window. The process parameters were optimized for improved hardness and tensile strength. The hardness property of the welded joints was measured using Brinnel hardness tester while the tensile strength was measured using Instron universal testing machine. Within the range of parameters utilized in this work, the hardness and tensile strength of the friction stir welded joint of AA1100 ranged between 15.30—35.32 BHN and 48.66 – 99.12 MPa respectively. The highest hardness value of 35.32 BHN was found at optimum parametric setting of 900 rpm rotational speed, 40 mm/min traverse speed and 2o tilt angle while the highest tensile strength of 99.12 MPa was obtained at optimal processing parameters of 900 rpm rotational speed, 25 mm/min traverse speed and 2o tilt angle. The ANOVA revealed that rotational speed followed by tilt angle has the most significant effect on the tensile strength of the weldment. The tilt angle and the traverse speed effects were found significant on the hardness of the weldments.