About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Structure and Dynamics of Metallic Glasses
|
Presentation Title |
Non-affine thermal expansion process in glass transition |
Author(s) |
Song-Ling Liu, Yuan-Chao Hu |
On-Site Speaker (Planned) |
Song-Ling Liu |
Abstract Scope |
A novel experimental method for measuring the coefficient of thermal expansion of supercooled liquids is invented, as well as a new analytical methodology for determining the atomic-level thermal expansion. We find a general rule of 1.7 times thermal expansion from glass to liquid for twenty bulk metallic glasses. This rule does not apply to other types of glasses or pure metals but only works for bulk metallic glasses containing copper or nickel. We revealed using molecular dynamics that atomic shells of Cu (or Ni) with interatomic distances of 6.5-7.6 Å (or 6.4-7.6 Å for Ni) changed from 32 to 46 (or 48 for Ni), when Cu50Zr50 (or Ni50Zr50) enters its supercooled liquid, resulting in the sample's thermal expansion at the glass transition. This research provides insights on how bulk metallic glasses form and highlights the relevance of chemical order at an interatomic distance of 6.5-7.6 Å in driving glass transition. |
Proceedings Inclusion? |
Planned: |