Corpus ID: 221836285

A cracking oxygen story: a new view of stress corrosion cracking in titanium alloys

  title={A cracking oxygen story: a new view of stress corrosion cracking in titanium alloys},
  author={Sudha Joseph and Paraskevas Kontis and Yanhong Chang and Yitong Shi and Dierk Raabe and Baptiste Gault and David Dye},
  journal={arXiv: Materials Science},
  • Sudha Joseph, P. Kontis, +4 authors D. Dye
  • Published 22 September 2020
  • Physics, Materials Science
  • arXiv: Materials Science
Titanium alloys can suffer from halide-associated stress corrosion cracking at elevated temperatures e.g. in jet engines, where chlorides and Ti-oxide promote the cracking of water vapour in the gas stream, depositing embrittling species at the crack tip. Here we report, using isotopically-labelled experiments, that crack tips in an industrial Ti-6Al-2Sn-4Zr-6Mo alloy are strongly enriched (>5 at.%) in oxygen from the water vapour, far greater than the amounts (0.25 at.%) required to embrittle… Expand

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