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Updated: Jun 1, 2026
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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
Capillary-wave model for the solidification of dilute binary alloys
Alexander L Korzhenevskii1, Richard Bausch, Rudi Schmitz
1Institute for Problems of Mechanical Engineering, RAS, Bol'shoi prospect. V. O., 61, St Petersburg, 199178, Russia.
Summary
We developed a phase-field model for alloy solidification, revealing a new instability at the solidification front. This capillary wave interaction influences solute diffusion, impacting rapid-growth scenarios.
Area of Science:
- Materials Science
- Physical Chemistry
- Solidification Physics
Background:
- Understanding alloy solidification is crucial for materials processing.
- Existing models often rely on sharp-interface assumptions, limiting applicability in rapid-growth regimes.
- Nonequilibrium effects and solute diffusion dynamics at the solidification front are key factors.
Purpose of the Study:
- To develop a phase-field model for isothermal solidification of binary alloys.
- To investigate the interaction between capillary waves and the solute concentration field.
- To analyze nonequilibrium effects during rapid solidification and identify novel instabilities.
Main Methods:
- Utilizing a phase-field description for alloy solidification.
- Developing a model that avoids the sharp-interface assumption.
- Incorporating capillary wave dynamics and solute diffusion.
- Analytical evaluation of the model for specific applications.
Main Results:
- Established a model of interacting capillary waves and solute diffusion at the solidification front.
- Included nonequilibrium effects relevant for rapid solidification.
- Identified a novel instability arising from the interaction, distinct from the Mullins-Sekerka instability.
- The new instability shows similarities to phenomena observed in grain-boundary motion.
Conclusions:
- The developed phase-field model provides a more comprehensive description of alloy solidification, especially under rapid-growth conditions.
- The identified instability offers new insights into pattern formation during solidification.
- This work bridges the gap between sharp-interface and diffuse-interface models, incorporating crucial nonequilibrium physics.
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