Disentangling structural and kinetic components of the a-relaxation in supercooled metallic liquids
The particle motion associated to the a-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron tech- niques, we report the existence of microscopic structure-dynamics relationships in Pt42.5 Cu27 Ni 9.5P 21 and Pd...
| Autores: | , , , , , , , , , , , , , |
|---|---|
| Formato: | artículo |
| Fecha de publicación: | 2022 |
| País: | España |
| Recursos: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/386117 |
| Acesso em linha: | https://hdl.handle.net/2117/386117 https://dx.doi.org/10.1038/s42005-022-01099-4 |
| Access Level: | acceso abierto |
| Palavra-chave: | Supercooled liquids Metallic glasses Synchrotron radiation sources Glass Sincrotrons Vidres metàl·lics |
| Resumo: | The particle motion associated to the a-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron tech- niques, we report the existence of microscopic structure-dynamics relationships in Pt42.5 Cu27 Ni 9.5P 21 and Pd 42.5Cu 27 Ni9.5 P21 liquids which allows us to disentangle structural and kinetic contributions to the a-process. While the two alloys show similar kinetic fragilities, their structural fragilities differ and correlate with the temperature dependence of the stretching parameter describing the decay of the density fluctuations. This implies that the evolution of dynamical heterogeneities in supercooled alloys is determined by the rigidity of the melt structure. We find also that the atomic motion not only reflects the topological order but also the chemical short-range order, which can lead to a surprising slowdown of the a- process at the mesoscopic length scale. These results will contribute to the comprehension of the glass transition, which is still missing. |
|---|