Related Experiment Video
Updated: Aug 18, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.6K
Phonon behavior in a random solid solution: a lattice dynamics study on the high-entropy alloy FeCoCrMnNi
Shelby R Turner1,2,3, Stéphane Pailhès3, Frédéric Bourdarot4
1Institut Laue-Langevin, F-38042, Grenoble, France.
Nature Communications
|December 6, 2022
Summary
High-entropy alloys (HEAs) exhibit unique lattice dynamics, bridging crystalline and disordered materials. This study reveals long-propagating acoustic phonons in HEAs, impacting their thermal properties.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- High-entropy alloys (HEAs) are advanced crystalline materials with multiple principal elements, known for exceptional mechanical properties.
- Their inherent chemical disorder suggests phonon behavior similar to glasses, impacting thermal transport.
- However, the long-range order in HEAs complicates their classification relative to disordered materials.
Purpose of the Study:
- To investigate the lattice dynamics of a representative HEA (Fe20Co20Cr20Mn20Ni20).
- To elucidate the unique phonon behavior of HEAs and their position between crystalline and disordered materials.
- To understand the relationship between phonon dynamics and thermal properties in HEAs.
Main Methods:
- Inelastic neutron scattering (INS) experiments.
- Inelastic X-ray scattering (IXS) experiments.
- Comprehensive analysis of lattice dynamics.
Main Results:
- Demonstrated unique phonon dynamics in HEAs, distinct from both fully ordered crystals and glasses.
- Observed long-propagating acoustic phonons across the entire Brillouin zone.
- Provided experimental evidence for HEAs existing at the frontier of ordered and disordered material behavior.
Conclusions:
- HEAs possess a unique phonon dynamic regime.
- The presence of long-propagating acoustic phonons influences their thermal transport characteristics.
- HEAs represent a distinct class of materials with complex lattice dynamics.
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