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Updated: Jul 13, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Reversible atomic processes as basic mechanisms of the glass transition
Feng Ye1, Wolfgang Sprengel, Rainer K Wunderlich
1Institut für Theoretische und Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany. yefeng@skl.ustb.edu.cn
Summary
Researchers directly observed reversible vacancy defects in Zr57Cu15.4Ni12.6Nb5Al10 glass. Vacancy migration is temperature-dependent, impacting glass properties and amorphous steel development.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Amorphous Materials
Background:
- Understanding defects in amorphous materials is crucial for predicting properties.
- Amorphous alloys, like Zr-based bulk metallic glasses, exhibit unique characteristics.
- Defect kinetics influence material behavior, including viscosity and structural stability.
Purpose of the Study:
- To directly evidence the reversible formation and disappearance of vacancy-type defects in bulk Zr57Cu15.4Ni12.6Nb5Al10 glass.
- To investigate the temperature dependence of vacancy kinetics.
- To correlate vacancy behavior with macroscopic properties like viscosity.
Main Methods:
- High-resolution, time-differential dilatometry was employed.
- Dilatometry precisely measured volume changes associated with defect formation/annihilation.
- Kinetic analysis was performed to determine migration enthalpy.
Main Results:
- Direct evidence for reversible vacancy-type defects was obtained.
- Vacancy kinetics were found to be strongly temperature-dependent.
- An effective migration enthalpy (HVM) of 3.34 eV was determined.
Conclusions:
- The observed vacancy dynamics can explain the temperature dependence of glass properties, such as viscosity.
- These findings have broad implications for amorphous condensed matter and biomaterials.
- The study contributes to the technical development of amorphous steels.
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