| Autor: |
Yanlong Ma, Lei Liu, Xinxin Zhang, Fei Guo, Xiaorong Zhou, Mingbo Yang, Jingfeng Wang |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Journal of Magnesium and Alloys, Vol 11, Iss 11, Pp 4325-4337 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2213-9567 |
| DOI: |
10.1016/j.jma.2022.11.001 |
| Popis: |
It is recently suggested that air-formed film plays an important role in controlling corrosion resistance of Mg-Li alloys. However, the structure of the air-formed film and its effect on corrosion resistance of Mg-Li alloys has not been fully understood. Firstly, the air-formed films formed on α and β phases in a dual-phase LZ91 Mg-Li alloy after exposure to laboratory air for up to 48 h have been examined by SEM under the assistance of ultramicrotomy. Then, the effect of the air-formed film on surface potential and, consequently, corrosion/oxidation behavior of the alloy has been investigated. Finally, in order to exclude the influence from α phase, the structure of the air-formed film on β phase and its effect on corrosion/oxidation behavior of Mg-Li alloys have been studied based on a single-phase LA141 Mg-Li alloy. The results show that the air-formed film is thin and negligible on α phase but thick on β phase after prolonged exposure to laboratory air. The thick air-formed film on β phase has a multilayer structure with an inner layer consisting of MgO/Mg(OH)2 and outer layer consisting of Li2CO3, which greatly elevates the surface potential of β phase in air. Both LZ91 and LA141 Mg-Li alloys firstly undergo uniform corrosion and then filiform corrosion when immersed in NaCl solution and the pre-existed air-formed film on β-Li phase can retard the occurrence of filiform corrosion in the alloys. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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