中國(guó)有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 35 No. 1 January 2025 |
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. State Key Laboratory of Power Metallurgy, Central South University, Changsha 410083, China;
3. Baoshan Iron & Steel Co., Ltd., Shanghai 201900, China;
4. Warwick Manufacturing Group, The University of Warwick, Coventry, CV4 7AL, UK;
5. Guangdong Weiye Aluminum Factory Group Co., Ltd., Foshan 528000, China）
Abstract:The corrosion behavior and microstructure characteristics of metal inert gas (MIG) welded dissimilar joints of the 6005A alloy modified with Sc (designated as 6005A+Sc) and the 5083 alloy were investigated using corrosion tests and microscopy techniques. Results show that the dissimilar joints exhibit strong stress corrosion cracking (SCC) resistance, maintaining substantial strength during slow strain rate tensile tests. Notably, the heat-affected zone (HAZ) and base metal (BM) on the 6005A+Sc side show superior performance in terms of inter-granular corrosion (IGC) and exfoliation corrosion (EXCO) compared to the corresponding zones on the 5083 side. The lower corrosion resistance of the 5083-BM and the 5083-HAZ can be attributed to the presence of numerous Al2Mg3 phases and micro-scaled Al6(Mn,Fe) intermetallics, mainly distributed along the rolling direction. Conversely, the enhanced corrosion resistance of the 6005A+Sc-BM and the 6005A+Sc-HAZ can be attributed to the discontinuously distributed grain boundary precipitates (β-Mg2Si), the smaller grain size, and the reduced corrosive current density.
Key words: metal inert gas welding; dissimilar joint; aluminum alloy; corrosion, microstructure
