Computational Studies of Amorphous UO2 for Grain Boundary Behavior

Ember L. Sikorski, Eric B. Nelson, Simon C. Middleburgh, Lan Li

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

Fission products at the point of contact between the pellet and the cladding contribute to the ultimate failure of the cladding through stress corrosion cracking (SCC). Gaseous fission products navigate along the grain boundaries after formation and eventually reach the plenum. To better understand fission product behavior at fuel grain boundaries, we generated random amorphous UO2 structures, as highly disordered grain boundaries exhibit the fastest kinetic properties. These structures were then optimized using ab initio methods and the most stable structure was selected for defect calculations. We have compared the atomic structure of UO2 structures with and without antiferromagnetism and calculated the incorporation energies of I, Te, and Xe in the grain boundaries of UO2. Each of the studied fission products favored the O-poor boundary. The grain boundary itself showed changes in lattice parameter lengths and angles after both vacancy formation and fission product incorporation.

Original languageAmerican English
Title of host publicationGLOBAL 2019: International Nuclear Fuel Cycle Conference and TOP FUEL 2019 - Light Water Reactor Fuel Performance Conference
StatePublished - 1 Jan 2020

Keywords

  • calculations
  • fission products
  • grain boundaries
  • light water reactors
  • nuclear fuel reprocessing
  • uranium dioxide

EGS Disciplines

  • Materials Science and Engineering

Fingerprint

Dive into the research topics of 'Computational Studies of Amorphous UO2 for Grain Boundary Behavior'. Together they form a unique fingerprint.

Cite this