| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Structure and Dynamics of Metallic Glasses
|
| Presentation Title |
Two-Stage, Non-Classical Crystal Nucleation from the Supercooled Liquid of a Metallic Glass Alloy |
| Author(s) |
Carter Francis, Shuoyuan Huang, Paul Voyles |
| On-Site Speaker (Planned) |
Paul Voyles |
| Abstract Scope |
In situ 4D STEM experiments reveal non-classical, two-stage nucleation of crystals during isothermal annealing in the supercooled liquid state above Tg of Pd77.7Cu4Si16.3 metallic glass alloy. Instead of forming an ordered crystal embryo with a crystal-liquid interface, we observe first the formation of a nanometer-diameter object with disordered structure. This structure has indistinguishable composition from the liquid, and persists for 10 to 100 times the liquid structural relaxation time. A crystal then forms inside the disordered precursor, grows to consume it, then grows by consuming the liquid. The precursors form without a measurable delay time, but there is a delay for nucleation of crystals. Only some precursors nucleate crystals; others dissolve into the liquid. This behavior is similar to amorphous precursor particles in crystal nucleation from aqueous solution, but these results are distinct in that we observe non-classical nucleation of a crystal from a liquid of the same composition. |
| Proceedings Inclusion? |
Planned: |