Effects of microstructural characteristics on the hydrogen embrittlement characteristics of austenitic, ferritic, and γ–α duplex stainless steels

Mitsuhiro Okayasu, Takafumi Fujiwara

Research output: Contribution to journalArticlepeer-review

Abstract

Hydrogen embrittlement (HE) characteristics of γ (AS), α (FS), and γ–α duplex (DS) stainless steels were examined experimentally and numerically. Severe HE occurred in the DS sample, whereas weak HE was detected in the AS and FS samples. This was attributed to the high hydrogen concentrations at the DS-trapping sites. Hydrogen trapping occurred in the low atomic density zones in the boundaries between α and γ phases in DS sample. The chemical bonding between atomic-scale phase boundaries was weakened by hydrogen penetration. This resulted in a crack growth along the DS α/γ phase boundaries. The ductility of DS decreased as the hydrogen content increased, especially when it exceeded 15 ppm. In contrast, the weak HE observed among AS and FS samples was attributed to the small hydrogen levels that infiltrated both samples. Finally, HE mechanism was proposed on the basis of these experimental results.

Original languageEnglish
Article number140851
JournalMaterials Science and Engineering A
Volume807
DOIs
Publication statusPublished - Mar 11 2021

Keywords

  • Austenite
  • Duplex phase
  • Ferrite
  • Hydrogen embrittlement
  • Stainless steel

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Effects of microstructural characteristics on the hydrogen embrittlement characteristics of austenitic, ferritic, and γ–α duplex stainless steels'. Together they form a unique fingerprint.

Cite this