| 摘要: |
| 采用搅拌摩擦焊方法对带有缺陷的2219铝合金变极性等离子弧熔焊接头进行补焊，焊后对补焊接头的微观组织和力学性能及断裂特性进行了分析。研究结果表明：补焊接头焊核区由细小的等轴再结晶组织构成；热机影响区内的组织发生了较大的弯曲变形；热影响区组织明显粗化。力学试验表明：补焊接头的抗拉强度比熔焊接头提高18％以上，延伸率可以提高一倍，接头性能得到明显改善。断口形貌分析显示，接头断裂模式为韧性和脆性的混合型断裂。 |
| 关键词: 搅拌摩擦补焊 2219铝合金 接头组织 力学性能 断裂特性 |
| 基金项目: |
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| Friction Stir Repaired Welding onVariable Polarity Plasma Arc Welding Joint of 2219 Aluminum Alloy |
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Wang Guoqing1, Du Yanfeng2,3, Feng Xiuyun3, Zhao Yanhua3, Liu Zhiyong4
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1. China Academy of Launch Vehicle Technology, Beijing 100076;2. BeiHang University, Beijing 100191;3. Capital Aerospace Machinery Company, Beijing 100076;4. China Enfi Engineering Corporation, Beijing 100038
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| Abstract: |
| Friction stir repaired welding (FSRW) has been successfully used to repair variable polarity plasma arc (VPPA) welding joints of 2219 Al alloy. The metallurgy experiment demonstrates that the FSRW joint microstructures could be divided into three different regions. The weld nugget consist of refined, equiaxed grains and the microstructures in TMAZ consist of highly deformed grains. The microstructure in HAZ consists of coarse grains which are much bigger than that in the nugget. Mechanical property measurements demonstrate that the mechanical properties of FSRW joint is much better than the VPPA welding joint. The peak tensile strength of FSRW joint can reach 118% of the VPPA welding joint, and the ductibility is as double as that of VPPA welding joint. The fracture analysis shows that the fracture mode of the FSRW joints is ductile/brittle mixed fracture. |
| Key words: friction stir repaired welding 2219 Al alloy joint microstructures mechanical property fracture mode |
