The general corrosion behavior of ENiCrFe-7 weld overlay cladding material in deoxygenated high-temperature and high-pressure water. Issue 4 (3rd April 2019)

• Record Type: Journal Article
• Authors: Guo, Peiliang; Zhu, Ping; Cao, Xinyuan; Wang, Wei; Ling, Ligong; Lu, Yonghao; Shoji, Tetsuo
• Is Part Of: Journal of nuclear science and technology. Volume 56:Issue 4(2019)
• Page Start: 355
• Page End: 363
• Publication Date: 2019-04-03
• Subjects: Corrosion -- preferential corrosion site -- weight gain -- oxide film -- pitting -- precipitation; Nuclear engineering -- Periodicals; Nuclear physics -- Periodicals; Nuclear energy -- Periodicals; 621.4805
• DOI: 10.1080/00223131.2019.1571453
• Languages: English
• ISSNs: 0022-3131

Abstract

ABSTRACT: The general corrosion behavior of Alloy ENiCrFe-7 in deoxygenated high-temperature and high-pressure water was investigated. The results showed that the precipitates of Alloy ENiCrFe-7 included niobium carbide and Al-Ti-O compounds, and the weight gain increased fast firstly before 2250 h, then the weight gain slowed down. There were obvious large particles spread on denser oxide film after 3000 h exposure. Ni was present at a single chemical metallic Ni state, Fe n+ content of the outer layer was close to 60%, which was much higher than that of the matrix. The oxide film consisted of an inner layer and an outer layer, the inner layer was mainly composed of Cr2 O3 and the outer layer was mainly composed of Fe3 O4 and FeCr2 O4 . Finally, it is found that the preferential corrosion location of pitting was niobium carbide precipitates by in same site observation, while Al-Ti-O compounds was not dissolved in deoxygenated high-temperature and high-pressure water for 1500 h exposure. The size and number of the pitting was not significantly changed with increasing exposure time.