Friction stir welding characteristics of 6061-T6 aluminum alloy sheet
(1.黑龙江省哈尔滨市哈尔滨工业大学现代焊接生产技术国家重点实验室2.State Key Laboratory of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin 150001, China)
Abstract: A 3mm-thick 6061-T6 aluminum alloy sheet was friction stir welded in order to examine its friction stir welding (FSW) characteristics. The experimental results indicate that the FSW clearly softens the aluminum alloy sheet, thus the tensile properties of the joints are lower than those of the base material, and the ultimate strength efficiency of the joints is only up to 66%. The FSW parameters significantly affect the tensile properties of the joints, and the range of the welding parameters that can be used to form a good joint is relatively narrow. All the FSW joints fracture on the retreating side of the weld center. When the revolutionary pitch is smaller than a certain critical value, the fracture locations are distant from the weld center. Otherwise, the fracture almost occurs in the weld center.
Key words: aluminum alloy； friction stir welding； tensile property； fracture location； welding parameter