| About this Abstract |
| Meeting |
2010 TMS Annual Meeting & Exhibition
|
| Symposium
|
Computational Thermodynamics and Kinetics
|
| Presentation Title |
Modeling of Phase Separation in Uranium-Zirconium Alloys via Monte Carlo Methods |
| Author(s) |
Benjamin W Beeler, Benjamin Good, Chaitanya Deo, Sergey Rashkeev, Maria Okuniewski, Mike Baskes |
| On-Site Speaker (Planned) |
Benjamin W Beeler |
| Abstract Scope |
U-Zr alloys are used as the fuel matrix in sodium cooled fast nuclear reactors. They have a body centered cubic structure (γ phase) that exhibits a miscibility gap at the temperature of operation. The alloy exhibits a variation in composition under operation with zirconium atoms migrating up the temperature gradient in the high temperature γ phase. We study the two phase evolution of U-Zr using a kinetic Monte Carlo (kMC) simulation which is well suited for studying diffusion-based phase transformations. We utilize an extension of the Ising model that accounts for atom transport through vacancy migration and allows a physically meaningful definition of time. The kMC simulation is linked to first-principles calculations via the implementation of local, composition-dependant values of the migration barrier energy. The short-range order, vacancy diffusion coefficient, and self-diffusion coefficients of uranium and zirconium are determined. The variance of these parameters with temperature and composition is analyzed. |
| Proceedings Inclusion? |
Definite: A CD-only volume |