**About this Abstract** |

**Meeting** |
**2016 TMS Annual Meeting & Exhibition
** |

**Symposium
** |
**Computational Materials Engineering for Nuclear Reactor Applications
** |

**Presentation Title** |
3D Phase Field Simulation of Grain Growth in Porous UO2 |

**Author(s)** |
Karim Ahmed, Yongfeng Zhang, Todd Allen, Michael Tonks, Anter El-Azab |

**On-Site Speaker (Planned)** |
Karim Ahmed |

**Abstract Scope** |
We present a 3D phase field model for investigating the grain growth process in porous UO2. The model captures the coevolution of grain size and porosity via coupling the curvature-driven motion of the grain boundary to the surface diffusion-driven motion of the pores. Therefore, the model is able to account for all possible interactions between the pore and the grain boundary, which affect the overall growth rates. Through a formal asymptotic analysis, the phase field model was matched to its sharp-interface counterpart and all the model parameters were uniquely determined. The simulations of the model were carried out using the mesoscale simulator MARMOT developed at Idaho National Laboratory. The model is used to quantify the effect of pore drag on the kinetics of grain growth in UO2. The effects of pore fraction, grain and pore size distributions, and pore configurations on the grain growth process were investigated. |

**Proceedings Inclusion?** |
Planned: A print-only volume |