Phase Diagram of Binary Alloy Nanoparticles under High Pressure
Han Gyeol Kim1, Joonho Lee1, Guy Makov2
1Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.
Materials (Basel, Switzerland)
|June 2, 2021
Summary
The CALPHAD method was used to study A-B nanoparticle phase diagrams under pressure. Eutectic temperatures typically decreased, but rose under specific conditions involving interaction and volume parameters.
Area of Science:
- Materials Science
- Thermodynamics
- Computational Materials Science
Background:
- The CALPHAD (Calculation of PHAse Diagram) method is crucial for constructing phase diagrams.
- CALPHAD applications have expanded to include nanophase and pressure-dependent phase diagrams.
- Understanding material behavior under pressure is vital for various applications.
Purpose of the Study:
- To investigate the pressure-dependent phase diagram of an arbitrary A-B nanoparticle system.
- To analyze the influence of interaction parameters and excess volume on the phase diagram under pressure.
Main Methods:
- Utilized the CALPHAD methodology for thermodynamic modeling.
- Simulated an A-B binary nanoparticle system.
- Varied pressure, interaction parameters, and excess volume to observe phase diagram changes.
Main Results:
- The eutectic temperature generally decreased with increasing pressure.
- An exception was observed where the eutectic temperature increased under specific conditions.
- These conditions included a zero interaction parameter in the liquid, a positive interaction parameter in the solid, and a positive excess volume parameter in the liquid.
Conclusions:
- Pressure significantly influences the phase diagram of A-B nanoparticle systems.
- The interplay between interaction parameters and excess volume dictates the response of eutectic temperature to pressure.
- Specific thermodynamic conditions can lead to counterintuitive increases in eutectic temperature with pressure.
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