**About this Abstract** |

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

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

**Presentation Title** |
Z-8: Phase Field Model of Multiphase Hydrides in Zirconium Fuel Rod Claddings |

**Author(s)** |
Jake Bair, Mohsen Asle Zaeem, Michael Tonks, Daniel Schwen |

**On-Site Speaker (Planned)** |
Jake Bair |

**Abstract Scope** |
Precipitation of zeta, gamma, and delta hydride phases has been simulated for nuclear fuel claddings using a kinetic phase field model. All previous studies have involved only one hydride phase. Using the model with all phases shows the nucleation path leading to the formation of the more mechanically detrimental delta phase. Non-conserved structural field variables are used to represent each phase including the alpha Zr matrix. Concentration of H is controlled using a conserved field variable. The Ginzburg-Landau and Cahn-Hilliard equations are used to solve the evolution of the nonconserved order parameters and concentration respectively.The model is implemented using the finite element method in Idaho National Laboratory's MARMOT mesoscale fuel performance code. |

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