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arXiv · 1602.03999

{\omega} structure in steel: a first-principles study

Yuji Ikeda·Isao Tanaka
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Abstract

Recent experimental works reported observation of the {\omega} structure in steel. Here, stability of the {\omega} structure in steel is investigated based on first-principles with special interests in effects of interstitial C atoms. The interstitial C atoms increase the energy of the {\omega} structure compared with the ferromagnetic (FM) BCC. The {\omega} structure incorporating C atoms is also mechanically unstable unless the C concentration is 25 at.%. It is concluded that the {\omega} structure is mostly unstable in steel, and the {\omega} structure in steel may be formed under special atomic constraints at twin boundaries or other interfaces.

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Yuji Ikeda, Isao Tanaka. 2016-02-12. {\omega} structure in steel: a first-principles study. https://doi.org/10.1016/j.jallcom.2016.05.211

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