Linking stress-driven microstructural evolution in nanocrystalline aluminium with grain boundary doping of oxygen

He MR, Samudrala SK, Kim G, Felfer P, Breen AJ, Cairney JM, Gianola DS (2016)

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2016

Journal

Nature Communications Nature Publishing Group: Nature Communications

Publisher: Nature Publishing Group: Nature Communications

Book Volume: 7

Article Number: 11225

DOI: 10.1038/ncomms11225

Abstract

The large fraction of material residing at grain boundaries in nanocrystalline metals and alloys is responsible for their ultrahigh strength, but also undesirable microstructural instability under thermal and mechanical loads. However, the underlying mechanism of stress-driven microstructural evolution is still poorly understood and precludes rational alloy design. Here we combine quantitative in situ electron microscopy with three-dimensional atom-probe tomography to directly link the mechanics and kinetics of grain boundary migration in nanocrystalline Al films with the excess of O atoms at the boundaries. Site-specific nanoindentation leads to grain growth that is retarded by impurities, and enables quantification of the critical stress for the onset of grain boundary migration. Our results show that a critical excess of impurities is required to stabilize interfaces in nanocrystalline materials against mechanical driving forces, providing new insights to guide control of deformation mechanisms and tailoring of mechanical properties apart from grain size alone.

Authors with CRIS profile

Peter Felfer Professur für Atom Probe Tomography

Additional Organisation(s)

Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM) Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Involved external institutions

University of Sydney (USYD) AU Australia (AU) University of Pennsylvania US United States (USA) (US)

How to cite

APA:

He, M.-R., Samudrala, S.K., Kim, G., Felfer, P., Breen, A.J., Cairney, J.M., & Gianola, D.S. (2016). Linking stress-driven microstructural evolution in nanocrystalline aluminium with grain boundary doping of oxygen. Nature Communications, 7. https://dx.doi.org/10.1038/ncomms11225

MLA:

He, Mo-Rigen, et al. "Linking stress-driven microstructural evolution in nanocrystalline aluminium with grain boundary doping of oxygen." Nature Communications 7 (2016).

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