About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Phonons, Electrons and Dislons: Exploring the Relationships Between Plastic Deformation and Heat
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Presentation Title |
Inelastic Neutron Scattering Investigation of the Phonon Spectra of Dislocated Nb Crystals |
Author(s) |
Sean R. Agnew, Thomas R. Bieler, Matthew B. Stone |
On-Site Speaker (Planned) |
Sean R. Agnew |
Abstract Scope |
Even modest dislocation densities have been shown to have a profound impact upon the phonon-dominated heat transfer of Nb near 2K. At higher temperatures, heat transfer is primarily electron-mediated, so the effect of dislocations on phonon behavior cannot be assessed using measurements of thermal transport alone. At very high dislocation densities, it has been predicted that even single-atom unit cells may exhibit an optical phonon mode. Inelastic neutron spectroscopy (INS) experiments on the Wide Angular-Range Chopper Spectrometer (ARCS) at the Spallation Neutron Source at Oak Ridge National Laboratory are used to examine the phonon spectra of highly pedigreed single crystals of Nb in the highly annealed, uniaxially deformed to moderate strain levels (30%), and heavily rolled conditions at 4K, 50K, and 300K. The results will be discussed in the context of classical observations of thermal transport and modern dislon theory. |
Proceedings Inclusion? |
Planned: |