# Microstructure Development during Creep Deformation of 9Cr-1Mo-V-Nb Steel with Excess Nitrogen Introduced by Solution Nitriding – Multidimensional Scatter Diagram Analysis of STEM-EDS Maps by Machine Learning –

https://mdr.nims.go.jp/datasets/67f9325a-e824-4264-911b-1c1c53b8d671

## File

- [65_ISIJINT-2025-211.pdf](https://mdr.nims.go.jp/filesets/64ba267b-01ec-4f42-907a-2eec51317a73/download) ([Detail](https://mdr.nims.go.jp/filesets/64ba267b-01ec-4f42-907a-2eec51317a73.md))

## Id

67f9325a-e824-4264-911b-1c1c53b8d671

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2025-11-07T07:42:09.176011Z

## Updated at

2025-11-10T07:30:55.687016Z

## Published at

2025-11-10T07:25:05.732669Z

## Doi



## First published url

https://doi.org/10.2355/isijinternational.isijint-2025-211

## Date published

2025-09-15

## Recorded date published

2025

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: Microstructure Development during Creep Deformation of 9Cr-1Mo-V-Nb Steel
    with Excess Nitrogen Introduced by Solution Nitriding – Multidimensional Scatter
    Diagram Analysis of STEM-EDS Maps by Machine Learning –
  title_type: original
  lang: en

## Description

- description: Creep deformation and precipitation behavior of 9Cr–1Mo–V–Nb steel
    with excess nitrogen introduced by solution nitriding were investigated. Precipitation
    of Cr2N phase was confirmed in addition to M23C6 and MX phases in the tempered
    microstructure. The creep strength of the steel was significantly reduced by solution
    nitriding, while the creep rupture elongation was increased. To characterize the
    complex precipitation behavior of the nitrogen-added steel, a machine learning-based
    clustering method of the multidimensional scatter diagram of the X-ray intensity
    of the alloying elements in each pixel of a STEM-EDS map was developed. Reduced
    number density of precipitates and enhanced coarsening kinetics of both Cr2N and
    MX were proposed as the mechanism of weakening caused by excess nitrogen.
  description_type: abstract
  lang: und

## Creator

- name: Tomotaka Hatakeyama
  role: author
  orcid: https://orcid.org/0000-0002-2904-8177
  organization: National Institute for Materials Science
- name: Shuntaro Ida
  role: author
- name: Kota Sawada
  role: author
  orcid: https://orcid.org/0000-0001-7780-1648
  organization: National Institute for Materials Science
- name: Kyosuke Yoshimi
  role: author

## Contact agent



## Publisher

organization: Iron and Steel Institute of Japan

## Managing organization



## Keyword

- subject: nitrogen
  schema: not_defined
- subject: precipitation
  schema: not_defined
- subject: scatter diagram method
  schema: not_defined
- subject: k-means clustering
  schema: not_defined
- subject: creep deformation
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by-nc-nd/4.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo



## Journal

- title: ISIJ International
  issn: '13475460'
  volume: '65'
  issue: '10'
  start_page: 1529
  end_page: 1540
  article_number: ISIJINT-2025-211

## Conference



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## Instrument



## Instrument operator



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## Measurement method



## Specimen



## Chemical composition



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## Computational method



## Energy level/transition state



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## Custom property



## Fileset

- id: 64ba267b-01ec-4f42-907a-2eec51317a73
  filename: 65_ISIJINT-2025-211.pdf
  content_type: application/pdf
  size: 3532350
  md5: 7b4bb1e155bda36b997be586233d674f

## Thumbnail

fileset_id: 64ba267b-01ec-4f42-907a-2eec51317a73
filename: 65_ISIJINT-2025-211.pdf