The dislocation mechanism of stress corrosion embrittlement in Ti-6Al-2Sn-4Zr-6Mo

Tamara P. Chapman, Vassili A. Vorontsov, Ananthi Sankaran, David Rugg, Trevor C. Lindley, David Dye

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

An observation of the dislocation mechanisms operating below a naturally initiated hot-salt stress corrosion crack is presented, suggesting how hydrogen may contribute to embrittlement. The observations are consistent with the hydrogen-enhanced localized plasticity mechanism. Dislocation activity has been investigated through post-mortem examination of thin foils prepared by focused ion beam milling, lifted directly from the fracture surface. The results are in agreement with the existing studies, suggesting that hydrogen enhances dislocation motion. It is found that the presence of hydrogen in (solid) solution results in dislocation motion on slip systems that would not normally be expected to be active. A rationale is presented regarding the interplay of dislocation density and the hydrogen diffusion length.

Original languageEnglish
Pages (from-to)282-292
Number of pages11
JournalMetallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Volume47
Issue number1
DOIs
Publication statusPublished - 1 Jan 2016

    Fingerprint

Keywords

  • fatigue crack
  • stress corrosion cracking
  • edge dislocation
  • hydrogen diffusion
  • critical resolve shear stress

Cite this