title: Vacancy mechanism of high oxygen solubility and nucleation of stable oxygen-enriched clusters in Fe.
abstract: First-principles studies identify a vacancy mechanism underlying the unusually high O solubility and nucleation of stable O-enriched nanoclusters in defect-containing Fe. Oxygen, confined as an interstitial, shows an exceptionally high affinity for vacancies, an effect enhanced by spin polarization. If vacancies preexist, the O-vacancy pair formation energy essentially vanishes, allowing the O concentration to approach that of the vacancies. This O-vacancy mechanism enables the nucleation of O-enriched nanoclusters, that attract solutes with high O affinities (Ti and Y) and strengthen Fe-based alloys.
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6114, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Fu
authors.forename: Maja
authors.initials: M
authors.lastname: Krcmar
authors.forename: G S
authors.initials: GS
authors.lastname: Painter
authors.forename: Xing-Qiu
authors.initials: XQ
authors.lastname: Chen