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ID 60106
Author
Okayasu, Mitsuhiro Graduate School of Natural Science and Technology, Okayama University Kaken ID researchmap
Sato, Masaya Graduate School of Natural Science and Technology, Okayama University Kaken ID researchmap
Ishida, Daiki Graduate School of Natural Science and Technology, Okayama University
Senuma, Takehide Graduate School of Natural Science and Technology, Okayama University
Abstract
Hydrogen embrittlement (HE) characteristics in Fe–C–Mn-xNb steels were examined via various analyses, including electron backscatter diffraction analysis, scanning transmission electron microscopy and three-dimensional atom-probe tomography. For the investigation, the steel samples were prepared with varying Nb contents and heat treatment processes. The material properties of steel samples that were subjected to: (i) water quenching and (ii) quenching and tempering at 170 °C for 20 min, were determined to be nearly similar, although different degrees of HE were detected. After the tempering process, ε-carbide precipitated clearly in the matrix, which could act as a trapping site for hydrogen atoms and lead to improved HE resistance. Moreover, with addition of Nb, niobium base precipitates (e.g., NbC) with a diameter of a few nanometers were obtained in the martensite matrix, which could also function as hydrogen trapping sites. There was slight improvement in the HE resistance with NbC. Hydrogen-assisted failure mechanisms under both static and cyclic loading were observed with intergranular brittle cracking for the water quenched sample, even though the brittle and ductile mix failure mode was detected for the sample after the quenching and tempering process.
Keywords
Steel
Hydrogen embrittlement;
Trapping site
Niobium carbide;
ε-carbide
Note
This fulltext is available in June 2022.
Published Date
2020-06-18
Publication Title
Materials Science and Engineering: A
Volume
volume791
Publisher
Elsevier
Start Page
139598
ISSN
0921-5093
NCID
AA10720420
Content Type
Journal Article
language
英語
OAI-PMH Set
岡山大学
Copyright Holders
© 2020 Elsevier B.V.
File Version
author
DOI
Related Url
isVersionOf https://doi.org/10.1016/j.msea.2020.139598
License
https://creativecommons.org/licenses/by-nc-nd/4.0/