4.5 Article

Corrosion characteristics and mechanisms of typical Ni-based corrosion-resistant alloys in sub- and supercritical water

Journal

JOURNAL OF SUPERCRITICAL FLUIDS
Volume 170, Issue -, Pages -

Publisher

ELSEVIER
DOI: 10.1016/j.supflu.2020.105138

Keywords

Supercritical water; Corrosion; Ni-based alloy; Corrosion resistance; Corrosion mechanism; Surface treatment process

Funding

  1. National Natural Science Foundation of China [22078258, 21576219]
  2. National Key Research and Development Program of China [SQ2019YFE011926]
  3. Joint Funds of Natural Science Basic Research Plan in Shaanxi Province of China [2019JLM-21]
  4. Fundamental Research Funds for the Central Universities [xtr042019015, xjh012019005]
  5. China Postdoctoral Science Foundation [2019TQ0248]
  6. FUTURE (Fundamental Understanding of Transport Under Reactor Extremes), an Energy Frontier Research Center - U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES)

Ask authors/readers for more resources

The corrosion characteristics and mechanisms of Ni-Fe-Cr and Ni-Fe-Cr-Mo-Cu corrosion-resistant alloys in supercritical water were discussed. Inconel 625 and Hastelloy C-276 showed good corrosion resistance in various testing environments. The outer oxide layer formation and potential causes of its looseness and discontinuity were also addressed. This information can guide material selection, design, and optimization of key equipment in supercritical water technologies.
The harsh work environments caused by high-temperature, high-pressure water, especially the presence of aggressive species such as oxygen and salts, makes equipment corrosion to be a key problem restricting large-scale industrial application of the supercritical water technologies. In this work, the corrosion characteristics of Ni-Fe-Cr and Ni-Fe-Cr-Mo-Cu corrosion-resistant alloys, such as the corrosion rate, the structure and composition of oxide film, and the effects of various surface treatment processes, are discussed in detail. The corrosion mechanisms of typical Ni-based alloys in supercritical water are analyzed. Inconel 625 and Hastelloy C-276 possess good corrosion resistance over a wide range of test environments, in terms of current investigation data regarding Ni-based alloys. The outer layer is formed by a metal passive dissolution-oxide precipitation mechanism, and the precipitated metal ions are released from the barrier layer. The looseness and discontinuity of the outer oxide layer can be attributed to the decomposition of oxides in the layer, the scouring of external fluids, or growth via electro-crystallization. This information is valuable for theoretically guiding material selection and design and operating parameter optimization of key equipment in the supercritical water technologies.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available