Hot corrosion behavior and near-surface microstructure of a 'low-temperature high-activity Cr-aluminide' coating on inconel 738LC exposed to Na2SO4, Na2SO4+ V2O5 and Na2SO4+ V2O5+ NaCl at 900 °C
| Autor: | K. Jafarzadeh, M. Salehi Doolabi, A. Habibollahzadeh, S.K. Sadrnezhaad, Behrooz Ghasemi |
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| Rok vydání: | 2017 |
| Předmět: |
010302 applied physics
Materials science General Chemical Engineering Metallurgy Oxide 02 engineering and technology General Chemistry engineering.material 021001 nanoscience & nanotechnology Microstructure 01 natural sciences Corrosion Superalloy chemistry.chemical_compound chemistry Cementation process Coating 0103 physical sciences engineering General Materials Science 0210 nano-technology Inconel Aluminide |
| Zdroj: | Corrosion Science. 128:42-53 |
| ISSN: | 0010-938X |
| Popis: | Hot corrosion is a serious problem in gas turbines due to poor quality fuels which contain Na, V, S and Cl. To resolve the problem, Cr-aluminide was coated on IN-738LC superalloy with a two steps pack cementation process. Oxidation behavior and near-surface microstructure of the coating showed consecutive increase in destruction by exposition to Na2SO4, 75Na2SO4 + 25 V2O5 and 70Na2SO4 + 25 V2O5 + 5NaCl (wt.%). Kinetic studies indicated parabolic corrosion rate in salt-less samples due to diffusion. Similar expression for salt-covered samples was assessed for oxide dissolution. Plate-like, broken-plate-like and cauliflower-like morphologies attributed to the corrosion products were observed after exposition to above three salts, respectively. |
| Databáze: | OpenAIRE |
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