# Pressure dependence of steam/supercritical water oxidation of 9Cr and 18Cr steel

https://mdr.nims.go.jp/datasets/8146c58b-691b-40d0-bd38-be53f70ce502

## File

- [20260430ISHOC2026_Abstract-TODA@NIMS.pdf](https://mdr.nims.go.jp/filesets/b1987458-6b1b-4e74-b362-164caef101dc/download) ([Detail](https://mdr.nims.go.jp/filesets/b1987458-6b1b-4e74-b362-164caef101dc.md))

## Id

8146c58b-691b-40d0-bd38-be53f70ce502

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-10-21T02:47:51.349347Z

## Updated at

2026-11-04T01:35:37.593492Z

## Published at

2026-11-04T03:32:01.220572Z

## Doi

https://doi.org/10.48505/nims.8696

## First published url



## Date published



## Recorded date published



## Resource type

conference_paper

## Manuscript type

authors_original

## Collection



## Title

- title: 9Cr鋼と18Cr鋼の水蒸気／超臨界水酸化の圧力依存性
  title_type: alternative
  lang: ja
- title: Pressure dependence of steam/supercritical water oxidation of 9Cr and 18Cr
    steel
  title_type: original
  lang: en

## Description

- description: 9Cr ferritic/martensitic heat-resistant steel and 18Cr austenitic steel
    were exposed for various durations in a pressure vessel to steam (0.5 MPa), subcritical
    water (10.2 MPa), and supercritical water (22.7 MPa) at 650 °C. The pressure dependence
    of the oxidation rate constants of each material was determined from the time
    dependence of specimen weight gain and oxide scale thickness due to oxidation.
    The oxidation rate constants of both steels decreased with increasing pressure.
    In steam, the oxidation rate constant of the 18Cr steel was smaller than that
    of the 9Cr steel. The difference between the two steels decreased with increasing
    pressure, and the oxidation rate constants of the two steels became almost identical
    in supercritical water. These results suggest that, at 650 °C, boilers and pressure
    vessels can be safely operated using higher-pressure steam or supercritical water
    at the same temperature if they are designed based on the oxidation behavior of
    heat-resistant steels in steam at atmospheric pressure. The decrease in the oxidation
    rate constants with increasing pressure is considered to result from the reduction
    in voids in the formed oxide scales, which decreases the contact area between
    dissolved oxygen in steam or supercritical water and the metal.
  description_type: abstract
  lang: eng

## Creator

- name: Yoshiaki Toda
  role: author
  orcid: https://orcid.org/0000-0002-8343-2890
  organization: National Institute for Materials Science
  department: Center for Basic Research on Materials/Data-driven Materials Research
    Field/Materials Modeling Group
- name: Nina Kobata
  role: author
  organization: National Institute for Materials Science
  department: Center for Basic Research on Materials/Data-driven Materials Research
    Field/Materials Modeling Group
- name: Xianglan Li
  role: author
  orcid: https://orcid.org/0000-0003-0992-1722
  organization: National Institute for Materials Science
  department: Advanced Engineering and Services Division/Materials Fabrication and
    Analysis Platform/Bioanalysis Unit
- name: Masahiko Demura
  role: author
  orcid: https://orcid.org/0000-0002-7308-3041
  organization: National Institute for Materials Science
  department: Center for Basic Research on Materials/Data-driven Materials Research
    Field/Materials Modeling Group

## Contact agent



## Publisher



## Managing organization



## Keyword

- subject: heat-resistant steel
  schema: not_defined
- subject: supercritical water
  schema: not_defined
- subject: subcritical water
  schema: not_defined
- subject: oxide scale
  schema: not_defined
- subject: parabolic law
  schema: not_defined
- subject: oxidation rate constant
  schema: not_defined
- subject: thermal power plant
  schema: not_defined

## Rights

- identifier: http://rightsstatements.org/vocab/InC/1.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo



## Journal



## Conference

name: International Symposium on High-temperature Oxidation and Corrosion 2026
start_date: 2026-10-18
end_date: 2026-10-23
identifier: https://pub.confit.atlas.jp/en/event/ishoc26

## Related item



## Funding

- identifier: 25K08550
  funder_name: JSPS
  description: Oxidation and Corrosion Behavior of Metallic Materials by Acidic Supercritical
    Water Mixed with Solid Particles
- funder_name: Iron and Steel Institute of Japan
  description: Oxidation and Corrosion Behavior of Heat-resistant Steels in Simulated
    Geothermal Fluids with High Temperature, Pressure, and Acidity

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



## Software



## Custom property



## Fileset

- id: b1987458-6b1b-4e74-b362-164caef101dc
  filename: 20260430ISHOC2026_Abstract-TODA@NIMS.pdf
  content_type: application/pdf
  size: 352521
  md5: b0efa5540129e96358f42bab24bc728b

## Thumbnail

fileset_id: b1987458-6b1b-4e74-b362-164caef101dc
filename: 20260430ISHOC2026_Abstract-TODA@NIMS.pdf