| Autor: |
Yuan Liu, Peng Hu, Haodong Duan, Jiamin Zeng, Mengmeng Wu, Yao Shi, Zilin Huang, Heng Zhang, Yanling Pei, Shusuo Li, Shengkai Gong, Dianyin Hu |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
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| Zdroj: |
Materials & Design, Vol 236, Iss , Pp 112486- (2023) |
| Druh dokumentu: |
article |
| ISSN: |
0264-1275 |
| DOI: |
10.1016/j.matdes.2023.112486 |
| Popis: |
Aluminide coatings are widely used on turbine blades due to their excellent oxidation resistance. However, the interdiffusion between these coatings and superalloy substrates can lead to a deterioration of mechanical properties in the coated alloys. In the present study, Ni-Al alloys (Ni-50Al, Ni-40Al, and Ni-30Al), both with and without the addition of 10 at. % Ru, are prepared and used to form diffusion couples with a single crystal superalloy SCA21. After a diffusion process at 1150 ℃ for 100 h, interdiffusion layers with the matrix of β-NiAl or γ ′-Ni3Al form at the diffusion couple interfaces. The formation of L12-ordered Ni3Al phases is found to impede elemental interdiffusion. Consequently, Ni-30Al/SCA21, which exhibits only Ni3Al-based interdiffusion layers, displays the lowest interdiffusion coefficients among the diffusion couples without Ru addition. Furthermore, first-principles studies reveal that the addition of Ru increases the formation energies of point defects and defect clusters involved in elemental interdiffusion in stoichiometric NiAl, Ni-rich NiAl, and Ni3Al phases, particularly when Ru occupies the Al site of Ni3Al phases at high temperatures. The remarkable diffusion barrier effects of Ru in Ni-30Al coatings have the potential to significantly enhance their performance and broaden their application prospects. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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