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08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
A numerical coarse-grained description of a binary alloy
J M Rickman1, T J Delph, E B Webb
1Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
The Journal of Chemical Physics
|August 17, 2012
Summary
This study uses Monte Carlo simulations to calculate the free energy of copper-nickel alloys. Histogram reweighting techniques allow for broad extrapolation of alloy properties across various conditions.
Area of Science:
- Computational Materials Science
- Thermodynamics
- Alloy Physics
Background:
- Understanding alloy behavior requires accurate free energy calculations.
- Coarse-grained models simplify complex material interactions.
- Embedded-atom methods provide a framework for atomic interactions.
Purpose of the Study:
- To determine the Ginzburg-Landau free energy for a copper-nickel (Cu-Ni) alloy using computational methods.
- To extrapolate free energy and thermodynamic properties over a wide parameter space.
- To compare simulation results with established alloy models.
Main Methods:
- Monte Carlo simulation in the semi-grand canonical ensemble.
- Tabulated histogram of joint probability density for composition, energy, and volume.
- Histogram reweighting techniques for extrapolation.
- Analysis of thermodynamic quantities using joint cumulants.
Main Results:
- The Ginzburg-Landau free energy for the Cu-Ni alloy was successfully determined.
- Free energy was extrapolated across a range of parameters using limited simulations.
- Expressions for thermodynamic quantities were derived and extrapolated.
Conclusions:
- The computational approach provides a robust method for determining alloy free energy.
- Histogram reweighting enables efficient exploration of alloy phase space.
- The method allows for prediction of composition dependence on temperature and chemical potential.
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