Grain boundary segregation of C, N and O in hexagonal close-packed titanium from first principles

Grain boundary segregation of light interstitials is one possible mechanism of thermal stability in commercially pure nanostructured titanium alloys. This paper uses first-principles calculations to show that the independent segregation of C, N and O atoms at a Σ7 high angle grain boundary in α -Ti is energetically unfavourable. The presence of interstitial elements near the grain boundary plane increases the grain boundary width and the specific formation energy.