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arXiv · 2103.01639

Revealing atomic-scale vacancy-solute interaction in nickel

Felipe F. Morgado·Shyam Katnagallu·Christoph Freysoldt·Benjamin Klaes·François Vurpillot·Jörg Neugebauer·Dierk Raabe·Steffen Neumeier·Baptiste Gault·Leigh T. Stephenson
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Abstract

Imaging individual vacancies in solids and revealing their interactions with solute atoms remains one of the frontiers in microscopy and microanalysis. Here we study a creep-deformed binary Ni-2 at.% Ta alloy. Atom probe tomography reveals a random distribution of Ta. Field ion microscopy, with contrast interpretation supported by density-functional theory and time-of-flight mass spectrometry, evidences a positive correlation of tantalum with vacancies. Our results support solute-vacancy binding, which explains improvement in creep resistance of Ta-containing Ni-based superalloys and helps guide future material design strategies.

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Felipe F. Morgado, Shyam Katnagallu, Christoph Freysoldt, Benjamin Klaes, François Vurpillot, Jörg Neugebauer, Dierk Raabe, Steffen Neumeier, Baptiste Gault, Leigh T. Stephenson. 2021-03-02. Revealing atomic-scale vacancy-solute interaction in nickel. https://doi.org/10.1016/j.scriptamat.2021.114036

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