Reaction mechanism of preoxidized nickel-chromium-cerium alloy with chlorine gas in the temperature range 400 C to 700 C
- Zhejiang Univ., Hangzhou (China). Dept. of Materials Science and Engineering
High-temperature corrosion of preoxidized Ni-Cr-Ce alloys in chlorine gas at temperatures between 400 C and 700 C was investigated using thermogravimetric analysis and examining the corrosion products by scanning electron microscopy, energy-dispersive spectroscopy, and x-ray diffraction. Corrosion resistance of preoxidized alloys against chlorination was improved by formation of protective nickel oxide-chromium oxide-cerium oxide scale. At lower temperature, the protective oxide scale played a role in the chlorination processes. With increasing reaction temperatures, the oxide scale was destroyed after exposure to Cl{sub 2} for a period of time. The corrosion rate increased rapidly, and weight decreased linearly with time. In Cl{sub 2} atmospheres at high temperature, Cl{sub 2} attacked the oxide scale by three mechanisms: mechanical damage by volatile chlorides, scale pitting and spalling by Cl{sub 2} dissolving in the scale, and oxides being converted to chlorides.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 477474
- Journal Information:
- Corrosion, Journal Name: Corrosion Journal Issue: 4 Vol. 53; ISSN 0010-9312; ISSN CORRAK
- Country of Publication:
- United States
- Language:
- English
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