Abstract
Microstructure is a controlling factor in the behavior of sintered materials. This work presents a quantitative phase field model of thermal sintering that predicts the evolution of the microstructure by capturing the sintering stress, GB/vacancy interactions, non-uniform diffusion, and grain coarsening without introducing a separate rigid body motion term. The model provides a mechanistic description of sintering using the grand potential phase field approach. Small test simulations are used to verify the new model against sintering theory, and they show that 3D simulations predict faster densification and coarsening than 2D simulations. 3D simulations are compared against experimental data available in the literature. The results of this comparison show that the model provides a reasonable estimate of the sintering behavior, though it overpredicts the sintering rate. This may be due to uncertainty in the material parameters and the relatively small scale of the simulation.
| Original language | English |
|---|---|
| Article number | 109288 |
| Journal | Computational Materials Science |
| Volume | 172 |
| DOIs | |
| State | Published - Feb 1 2020 |
| Externally published | Yes |
Funding
Funding for this work was provided by the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. The authors would like to thank the Idaho National Laboratory (INL) Fuel Modeling and Simulation department. Special thanks to Cody Permann of INL for his help in developing and using the tools used to perform the simulations in this paper, Daniel Schwen of INL for his input on mitigating the effects of surface roughness, and Paul Millett and Bruce Berry of the University of Arkansas for help with the code used to generate the ICs.
Keywords
- Computational model
- Phase field
- Sintering
- Uranium dioxide