Edge dislocation depinning from hydrogen atmosphere in α-iron

Kapci M. F., Yu P., Marian J., Liu G., Shen Y., Li Y., ...More

Scripta Materialia, vol.247, 2024 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 247
  • Publication Date: 2024
  • Doi Number: 10.1016/j.scriptamat.2024.116094
  • Journal Name: Scripta Materialia
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, DIALNET, Civil Engineering Abstracts
  • Keywords: Dislocation depinning, Hydrogen embrittlement, Hydrogen-dislocation interactions, Molecular dynamics
  • Abdullah Gül University Affiliated: Yes

Abstract

Understanding the dislocation motion in hydrogen atmosphere is essential for revealing the hydrogen-related degradation in metallic materials. Atomic simulations were adopted to investigate the interaction between dislocations and hydrogen atoms, where the realistic hydrogen distribution in the vicinity of the dislocation core was emulated from the Grand Canonical Monte Carlo computations. The depinning of edge dislocations in α-Fe at different temperatures and hydrogen concentrations was then studied using Molecular Dynamics simulations. The results revealed that an increase in bulk hydrogen concentration increases the flow stress due to the pinning effect of solute hydrogen. The depinning stress was found to decrease due to the thermal activation of the edge dislocation at higher temperatures. In addition, prediction of the obtained results was performed by an elastic model that can correlate the bulk hydrogen concentration to depinning stress.