Microstructure and Property of Friction Stir Welding Joint of 7075Al and AZ31BMg

doi:10.1007/s12204-012-1345-2

Abstract

Abstract: Microstructure and forming quality of friction stir welding joints of 7075Al and AZ31BMg with different welding parameters were analyzed. The results show that, good welded joint is obtained when the rotating frequency is 13 r/s and the welding speed is 30 mm/min. An irregular area is formed in the welding center. Meanwhile, the river pattern and eddy-like distribution are found in the weld nugget zone. Besides, brittle intermetallic compounds Al12Mg17 and Al3Mg2 are found in the welded joint. They cause the increase of microhardness of welded joint. The maximum tension stress of welded joint is 112MPa.

Key words: friction stir welding| aluminum alloy| magnesium alloy| microstructure| tension stress

摘要： Microstructure and forming quality of friction stir welding joints of 7075Al and AZ31BMg with different welding parameters were analyzed. The results show that, good welded joint is obtained when the rotating frequency is 13 r/s and the welding speed is 30 mm/min. An irregular area is formed in the welding center. Meanwhile, the river pattern and eddy-like distribution are found in the weld nugget zone. Besides, brittle intermetallic compounds Al12Mg17 and Al3Mg2 are found in the welded joint. They cause the increase of microhardness of welded joint. The maximum tension stress of welded joint is 112MPa.

关键词: friction stir welding| aluminum alloy| magnesium alloy| microstructure| tension stress

CLC Number:

TG 453

LI Da1,2 (李达), CUI Zhan-quan2 (崔占全), YANG Qing-xiang2* (杨庆祥),SUN Bing1 (孙兵), SUN Ming-hui2 (孙明辉). Microstructure and Property of Friction Stir Welding Joint of 7075Al and AZ31BMg[J]. Journal of shanghai Jiaotong University (Science), 2012, 17(6): 679-683.

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