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Updated: Aug 6, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Surface premelting and melting of colloidal glasses
Qi Zhang1, Wei Li1, Kaiyao Qiao1
1Department of Physics, Hong Kong University of Science and Technology, Hong Kong, China.
Science Advances
|March 17, 2023
Summary
Glass melting reveals distinct surface and intermediate layers, similar to crystal melting. These findings generalize premelting and melting phenomena to amorphous solids, offering insights into glass surface dynamics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- The liquid-to-glass transition is a fundamental scientific puzzle.
- Glass melting, particularly surface effects, remains poorly understood.
Purpose of the Study:
- To investigate the surface effects during glass melting.
- To explore the generalization of premelting and melting phenomena to amorphous solids.
Main Methods:
- Assembling colloidal glasses via vapor deposition.
- Melting colloidal glasses by tuning particle attractions.
- Analyzing structural and dynamic parameters at different depths.
Main Results:
- Identified a surface liquid layer and an intermediate glassy layer with distinct structural and dynamic properties.
- Observed power-law growth of both layers and melting front behavior analogous to crystal melting.
- Confirmed theoretical predictions for glass surface layer kinetics.
Conclusions:
- Premelting and melting phenomena can be generalized to amorphous solids.
- The study provides a deeper understanding of glass surface dynamics and melting behavior.
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