Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System
This study aimed to examine the corrosion behavior of Inconel 625 in a molten salt system of sodium sulfate and vanadium pentoxide at varying temperatures and durations. The corrosion products, microstructure, and element distribution of hot extruded Inconel in Na<sub>2</sub>SO<sub>...
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MDPI AG
2023-06-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/13/6/1069 |
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| author | Liang Li Lanfeng Li Guofeng Zhang Hongdi Xue Maomao Cui Wenxu Wang Dexue Liu |
| author_facet | Liang Li Lanfeng Li Guofeng Zhang Hongdi Xue Maomao Cui Wenxu Wang Dexue Liu |
| author_sort | Liang Li |
| collection | DOAJ |
| description | This study aimed to examine the corrosion behavior of Inconel 625 in a molten salt system of sodium sulfate and vanadium pentoxide at varying temperatures and durations. The corrosion products, microstructure, and element distribution of hot extruded Inconel in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> molten salt systems were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) analyses. This study demonstrates that corrosion of the alloy increases with time at a constant temperature. During the initial stage of corrosion, the surface of the alloy is primarily composed of a dense oxide layer consisting of Cr<sub>2</sub>O<sub>3</sub> and NiO. However, after exposure to the salt bath for 24 h, a chemical reaction occurs between the alloy and vanadium (V), resulting in the formation of CrVO<sub>4</sub> and Ni<sub>3</sub>V<sub>2</sub>O<sub>8</sub>. Furthermore, the intrusion of sulfur (S) element into the matrix leads to the formation of internal sulfides, including Ni-, Cr-, and Mo-based sulfides, which accelerate intergranular and intracrystalline corrosion. As the corrosion temperature rises, the surface microstructure of the corrosion layer transforms from powder to salt particles and then to massive particles. The corrosion products exhibit a clear stratification, while the alloy undergoes simultaneous oxidation and vulcanization processes. |
| first_indexed | 2024-03-11T02:10:44Z |
| format | Article |
| id | doaj.art-bc7913159d874f5ba559e48845d2eb66 |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-11T02:10:44Z |
| publishDate | 2023-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj.art-bc7913159d874f5ba559e48845d2eb662023-11-18T11:36:22ZengMDPI AGMetals2075-47012023-06-01136106910.3390/met13061069Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt SystemLiang Li0Lanfeng Li1Guofeng Zhang2Hongdi Xue3Maomao Cui4Wenxu Wang5Dexue Liu6School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, ChinaThis study aimed to examine the corrosion behavior of Inconel 625 in a molten salt system of sodium sulfate and vanadium pentoxide at varying temperatures and durations. The corrosion products, microstructure, and element distribution of hot extruded Inconel in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> molten salt systems were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) analyses. This study demonstrates that corrosion of the alloy increases with time at a constant temperature. During the initial stage of corrosion, the surface of the alloy is primarily composed of a dense oxide layer consisting of Cr<sub>2</sub>O<sub>3</sub> and NiO. However, after exposure to the salt bath for 24 h, a chemical reaction occurs between the alloy and vanadium (V), resulting in the formation of CrVO<sub>4</sub> and Ni<sub>3</sub>V<sub>2</sub>O<sub>8</sub>. Furthermore, the intrusion of sulfur (S) element into the matrix leads to the formation of internal sulfides, including Ni-, Cr-, and Mo-based sulfides, which accelerate intergranular and intracrystalline corrosion. As the corrosion temperature rises, the surface microstructure of the corrosion layer transforms from powder to salt particles and then to massive particles. The corrosion products exhibit a clear stratification, while the alloy undergoes simultaneous oxidation and vulcanization processes.https://www.mdpi.com/2075-4701/13/6/1069Inconel 625molten salt systemhot corrosioncorrosion mechanisminternal vulcanization |
| spellingShingle | Liang Li Lanfeng Li Guofeng Zhang Hongdi Xue Maomao Cui Wenxu Wang Dexue Liu Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System Metals Inconel 625 molten salt system hot corrosion corrosion mechanism internal vulcanization |
| title | Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System |
| title_full | Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System |
| title_fullStr | Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System |
| title_full_unstemmed | Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System |
| title_short | Hot Corrosion Behavior of Inconel 625 in Na<sub>2</sub>SO<sub>4</sub> and V<sub>2</sub>O<sub>5</sub> Molten Salt System |
| title_sort | hot corrosion behavior of inconel 625 in na sub 2 sub so sub 4 sub and v sub 2 sub o sub 5 sub molten salt system |
| topic | Inconel 625 molten salt system hot corrosion corrosion mechanism internal vulcanization |
| url | https://www.mdpi.com/2075-4701/13/6/1069 |
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