期刊
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
卷 34, 期 1, 页码 102-111出版社
JOURNAL MATER SCI TECHNOL
DOI: 10.1016/j.jmst.2017.11.015
关键词
Aluminum hollow extrusions; High-speed friction stir welding; Microstructures; Mechanical properties
资金
- National Natural Science Foundation of China [51435004, 51175117, U1404502]
- National Science and Technology Major Project of China [2010ZX04007-011]
The AA6005A-T6 aluminum hollow extrusions were friction stir welded at a high welding speed of 2000 mm/min and various axial forces. The results show that the nugget zone (NZ) is characterized by fine equiaxed grains, in which a low density of equilibrium phase beta is observed. The grains in the thermo-mechanically affected zone (TMAZ) are elongated, and the highest density of dislocations and a low density of beta' precipitates can be found in grains. The heat affected zone (HAZ) only experiences a low thermal cycle, and a high density of beta precipitates and a low density of beta' precipitates remain in the coarsened grains. The microhardness evolutions in the NZ, TMAZ and HAZ are governed by the grain refinement and dislocation strengthening, the dislocation and precipitation strengthening, and the precipitation and solid solution strengthening, respectively. When increasing the axial force, the changing trend of one strengthening mechanism is contrary to the other in each zone, and the microhardness increases in different zones. As a result, the tensile strength roughly increases with raising the axial force, and all joints show good tensile properties as the high welding speed inhibits the coarsening and dissolution of strengthening precipitates significantly. (C) 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据