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arXiv · 1302.4836

Grain boundary segregation of C, N and O in hcp titanium from first-principles

D. A. Aksyonov·A. G. Lipnitskii·Yu. R. Kolobov
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Abstract

It is believed that grain boundary segregation of light interstitials can serve as possible mechanism of thermal stability in commercially pure nanostructured titanium alloys. In this paper, using first-principles calculations, we show that independent segregation of C, N and O atoms at Σ7 high angle grain boundary in α-Ti is energetically unfavourable. The presence of interstitial elements near and at the grain boundary interface results in the increase of the grain boundary width and specific formation energy.

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D. A. Aksyonov, A. G. Lipnitskii, Yu. R. Kolobov. 2013-04-29. Grain boundary segregation of C, N and O in hcp titanium from first-principles. https://doi.org/10.1088/0965-0393%2F21%2F7%2F075009

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