Mechanistic understanding for the formation of Cr-rich haematite layer on the T12 ferritic steel in supercritical water

Xiangyu Zhong, Tetsuo Shoji, Tadashi Tatsuki, Jun Morii, Wakako Sasaki

Research output: Contribution to journalArticlepeer-review

Abstract

The oxides formed on T12 ferritic steel surface after exposure to 560 °C/25 MPa supercritical water with dissolved oxygen contents of 300 ppb was characterised by various techniques. It was found that the weight gain and thickness of the oxide scale increase with the increasing exposure time and the oxidation kinetics of T12 followed with parabolic law. The Cr content at the outermost layer increases while the Cr content at the inner/outer layer interface decreases with the increasing of exposure time. The Cr-rich haematite layer oxide was observed on the specimen surface when the test duration extended to 1000 h. The mechanism for the formation of the Cr-rich haematite layer was proposed based on the Cr can diffuse outward through the magnetite layer by short-circuits of the oxide layer and reach the magnetite/haematite interface.

Original languageEnglish
Pages (from-to)778-786
Number of pages9
JournalCorrosion Engineering Science and Technology
Volume56
Issue number8
DOIs
Publication statusPublished - 2021

Keywords

  • Ferritic steel
  • high temperature oxidation
  • oxide scale, supercritical water

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Science(all)

Fingerprint

Dive into the research topics of 'Mechanistic understanding for the formation of Cr-rich haematite layer on the T12 ferritic steel in supercritical water'. Together they form a unique fingerprint.

Cite this