Effect of Taper Pin Ratio on AA7075 Aluminium Alloy Friction Stir Welding

摘要

This study focuses on the effect of pin taper tool ratio on friction stir welding ofudaluminum AA7075. Two pieces of AA7075 alloy with thickness of 6 mm were friction stir weldedudby using conventional milling machine. The shoulder diameter used in this experiment is fixed atud18mm. The taper pin ratio used are varied at 6:6, 6:5, 6:4, 6:3, 6:2 and 6:1. The rotational speedsudthat were used in this study were 1000 rpm, 1200 rpm and 1400 rpm, respectively. The weldingudspeeds used are 60 mm/min, 80 mm/min and 100 mm/min. Microstructure observation of weldedudarea was studied by using optical microscope. To evaluate the mechanical properties of thisudspecimen, tensile test was used in this study. Welded specimens using taper pin ratio 6:2 showsudhigher tensile strength compared to other taper pin ratio up to 197 MPa. Moreover, specimens usingudtaper pin ratio 6:1 showed better tensile test compared to the ones using taper pin ratio above 6:3.udThe optimum parameters were found to be taper pin ratio 6:2 with 1000 rpm of rotational speed andud60mm/min welding speed