Effect of welding parameters on weld formation and mechanical properties in dissimilar al alloy joints by FSW

Abstract

The dissimilar Al alloys, 5052 and 5J32, were joined by friction stir welding (FSW) technique under several welding conditions, including material arrangement. The tool rotation speeds were 1000 and 1500rpm, and the welding speeds were varied within the range from 100 to 400 mm/mim. At a tool rotation speed of 1000 rpm, all joints with the 5052 on the advancing side exhibited better properties than those with the opposite arrangement. When the 5J32 was placed on the advancing side, defect-free welds were obtained under all welding conditions. However, when the 5J32 was placed on the retreating side with a rotation speed of 1500rpm, some defects were detected below the top surface of the retreating side. Furthermore, fractographs of the defects indicated an evidence of liquation cracking during FSW. The experimental results showed that the weld formation and mechanical properties depended upon the material arrangement as well as the conventional welding parameters.© 2010 The Japan Institute of Metals .