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Updated: Feb 11, 2026
12:02
Determination of Thermodynamic Properties of Alkaline Earth-liquid Metal Alloys Using the Electromotive Force Technique
Published on: November 3, 2017
13.7K
Monotropic polymorphism in a glass-forming metallic alloy.
S Pogatscher1, D Leutenegger, J E K Schawe
1Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland. Institute of Nonferrous Metallurgy, Montanuniversitaet Leoben, 8700 Leoben, Austria.
Summary
This study reveals a unique solid-liquid-solid transition in an amorphous metallic alloy (Au70Cu5.5Ag7.5Si17). The transition
Area of Science:
- Materials Science
- Metallurgy
- Solid-State Chemistry
Background:
- Amorphous metallic alloys exhibit complex phase transitions.
- A novel metastable melting and recrystallization phenomenon was previously observed in Au70Cu5.5Ag7.5Si17.
- Understanding these transitions is crucial for materials design.
Purpose of the Study:
- To investigate the crystallization and phase transition behavior of the amorphous metallic alloy Au70Cu5.5Ag7.5Si17.
- To explore the solid-liquid-solid transition under varying thermal conditions.
- To correlate microstructure with observed phase transitions.
Main Methods:
- Fast differential scanning calorimetry (FDSC) for thermal analysis.
- Scanning and transmission electron microscopy (STEM) for microstructural investigation.
- X-ray diffraction (XRD) and energy-dispersive X-ray spectrometry (EDX) for phase and chemical analysis.
Main Results:
- The solid-liquid-solid transformation in FDSC is dependent on initial sample conditions.
- History-dependent nucleation of the stable crystalline phase explains the transition variability.
- Microstructural analysis revealed distinct phases correlating with thermal events.
Conclusions:
- The occurrence of the solid-liquid-solid transition is sensitive to the formation history of the metastable phase.
- Kinetic pathways of the transition are influenced by nucleation events.
- This phenomenon offers insights into monotropic polymorphism in metallic alloys.
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