In friction stir welding （FSW）, tool geometry plays an important role in joint quality. In order to improve mechanical properties of friction stir lap welding （FSLW）joint, a tool with a reverse-threaded pin was de...In friction stir welding （FSW）, tool geometry plays an important role in joint quality. In order to improve mechanical properties of friction stir lap welding （FSLW）joint, a tool with a reverse-threaded pin was designed in the present study. Using 2024-T4 aluminum alloy as the research object, tools with the full- threaded pin and reverse-threaded pin were used in FSLW. Results showed that, when using the same parameter combination, FSLW joint using the reverse-threaded pin owned bigger effective sheet thick- ness （EST）, bigger lap width and better lap shear failure strength. Compared with the full-threaded pin, fracture mode of the FSLW joint changed from shear fracture mode to tensile fracture mode when the reverse-threaded pin was used. Fracture morphologies presented ductile fracture.展开更多
基金supported by the National Natural Science Foundation of China(No.51204111)the Natural Science Foundation of Liaoning Province(Nos.2013024004 and 2014024008)+1 种基金the Project of Science and Technology Department of Liaoning Province(No.2013222007)the Aeronautical Science Foundation of China(No.2014ZE54021)
文摘In friction stir welding （FSW）, tool geometry plays an important role in joint quality. In order to improve mechanical properties of friction stir lap welding （FSLW）joint, a tool with a reverse-threaded pin was designed in the present study. Using 2024-T4 aluminum alloy as the research object, tools with the full- threaded pin and reverse-threaded pin were used in FSLW. Results showed that, when using the same parameter combination, FSLW joint using the reverse-threaded pin owned bigger effective sheet thick- ness （EST）, bigger lap width and better lap shear failure strength. Compared with the full-threaded pin, fracture mode of the FSLW joint changed from shear fracture mode to tensile fracture mode when the reverse-threaded pin was used. Fracture morphologies presented ductile fracture.
