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Updated: Aug 1, 2025
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Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
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Eutectic crystallization and melting in sharp concentration gradients.
Andriy Gusak1,2, Anastasiia Titova1
1Ensemble3 Centre of Excellence, Wolczynska Str. 133, 01-919 Warsaw, Poland.
The Journal of Chemical Physics
|April 26, 2023
Summary
Contact melting requires a critical solid solution width. Crystallization in sharp gradients can form periodic structures, with temperature influencing the mechanism in Ag-Cu type eutectic systems.
Area of Science:
- Materials Science
- Physical Chemistry
- Solid State Physics
Background:
- Understanding phase transitions in multi-component systems is crucial for materials development.
- Sharp concentration gradients present unique challenges for studying melting and crystallization phenomena.
Purpose of the Study:
- To investigate the initial stages of contact melting and eutectic crystallization under sharp concentration gradients.
- To analytically and numerically simulate these processes for crystalline components.
Main Methods:
- Analytical modeling of contact melting and eutectic crystallization.
- Numerical simulations of phase transitions in systems with sharp concentration gradients.
- Investigation of Ag-Cu type eutectic systems.
Main Results:
- Contact melting is contingent upon the formation of a critical solid solution width.
- Crystallization within sharp concentration gradients can induce periodic interfacial structures.
- A threshold temperature exists for Ag-Cu type systems, altering crystallization mechanisms from 'precipitation + growth' to 'polymorphic crystallization + spinodal decomposition'.
Conclusions:
- The formation of solid solutions plays a critical role in initiating contact melting.
- Interface dynamics during crystallization are complex and can lead to ordered structures.
- Temperature-dependent mechanisms govern eutectic crystallization, impacting material properties.
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