| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Structure-Property Relationships of Bulk Metallic Glasses
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| Presentation Title |
Chemically-resolved Dynamics in Metallic Alloy Supercooled Liquids |
| Author(s) |
Shuoyuan Huang, Ajay Annamareddy, Dane Morgan, Paul Voyles |
| On-Site Speaker (Planned) |
Paul Voyles |
| Abstract Scope |
Electron correlation microscopy (ECM) measures atomic motions in liquids in the form of the structural relaxation time, τ. We have used ECM to study the diffraction angle, k, dependence of τ for Pt<sub>57.5</sub>Cu<sub>14.7</sub>Ni<sub>5.3</sub>P<sub>22.5</sub> and Pd<sub>43</sub>Cu<sub>10</sub>Ni<sub>27</sub>P<sub>20</sub> liquids. Because atom pairs of different composition diffract at different k, the τ(k) dependence provides separate relaxation times for pairs with different composition, such as Pt-Pt or Pd-P. In both alloys, the primary P-containing pair (Pt-P or Pd-P) has the fastest dynamics, in contrast to intuition based on semi-covalent P bonding. Fast dynamics for P are also found in simulations. Rotational symmetries in nanodiffraction data and Voronoi polyhedra in simulations suggest consistent, strong icosahedral ordering around Pt and Pd, but a wider variety of lower symmetry structure around P. Therefore, P may enhance glass forming ability in these alloys through high configurational entropy rather than low configurational energy. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Other, |