2016 Volume 57 Issue 6 Pages 988-994
Aluminum ships are increasingly being built these days according to the international marine environment contamination regulations. However, aluminum alloys are associated with many problems such as welding deformation. A basic study was conducted to address the problems using friction stir welding (FSW), a solid-state joining method. The AA 5083-O specimen was 2 mm-thick, and a device that provided five-axis processing control was used for the curvature welding to determine the feasibility of the process. X-ray was used to test the FSW joints quality and to examine inner defects. The characteristics of the FSW joints were evaluated based on the deformation after the welding, tensile strength, and Vickers hardness of each test specimen, according to the welding speed. The welding results were visually satisfactory for the approximate joint length of 200 mm. The joints strength was almost constant regardless of the welding speed. The joint efficiency was about 90% of that of the base material, while the elongation of the joints was about 50% of that of the base material. The hardness distribution of the joints was almost the same as that of the base material regardless of the heat input, which corresponds to the tensile test results.
