About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Computational Thermodynamics and Kinetics
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Presentation Title |
Magnetic-field-induced Phonon Stiffening Enhances Demagnetization Entropy in a Shape Memory Alloy |
Author(s) |
Michael E. Manley, Paul Stonaha, Nick Bruno, Ibrahim Karaman, Raymundo Arroyave, Douglas Abernathy, Songxue Chi, Jeffrey Lynn |
On-Site Speaker (Planned) |
Michael E. Manley |
Abstract Scope |
Magnetocaloric materials are of considerable interest due to their application in technologies such magnetic refrigeration. A class of magnetocaloric materials are magnetic shape memory alloys, which undergo a first-order phase transition at their martensitic transformation temperature. This talk will present a neutron scattering study of the lattice dynamics of the metamagnetic shape memory alloy Ni45Co5Mn36.6In13.4. We identify an anomalous temperature-dependent softening of an optic phonon below the Curie temperature, which we attribute to magneto elastic coupling. Further, we use in situ application of a magnetic field to show that the phonon is indeed coupled to the magnetism in the sample. Finally, we use measurements of the phonon density of states to show that the magnetic-field-induced phonon stiffening significantly enhances the demagnetization entropy. |
Proceedings Inclusion? |
Planned: |