Anisotropy in oxidation of zirconium surfaces from density functional theory calculations

Abstract

This work uses density functional theory calculations to analyze the energy barriers for oxygen migration into the basal and prismatic surfaces of zirconium. Specifically, the migration energy barriers between each octahedral site and tetrahedral site in the basal surface, prism surface, and the bulk are determined. The possible oxygen migration paths in each system are also analyzed. Oxygen has higher energy barriers to penetrating the basal surface than the prism surface. It also has a lower energy barrier to escape from basal surface than from the prism surface. This is consistent with the experimental observation that the prism plane of zirconium oxidizes more quickly than the basal plane.

Mechanistic materials modeling for nuclear fuel performance

“…However, because the fundamental oxidation chemical reaction is the same in the alloys, simple studies can provide value in characterizing oxidation mechanisms. For example, a simple DFT study of the oxidation of single crystal Zr with various surfaces exposed [138] showed an anisotropy in the oxygen adsorption, which is consistent with experiment [139]. In addition, first principles simulations have been applied to determine phase stability in the Zr-O system [140].…”

Insight into structural, mechanical, electronic and thermodynamic properties of intermetallic phases in Zr–Sn system from first-principles calculations

“…Sn is fundamental alloying element for Zr alloys as it improves oxidation resistance and mechanical properties. Modern density functional theory (DFT) simulations have shown its advantage and efficiency in investigating Zr intermetallic compounds [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. In spite of such encouraging results, some uncertainties concerning structural, mechanical and thermodynamic properties of equilibrium phases on Zr-Sn binary system still exist.…”

Effect of pores and He bubbles on the thermal transport properties of UO2 by molecular dynamics simulation

“…The effect of porosity on thermal transport in UO 2 has not yet been directly characterized at the atomic level. While there are a few atomistic simulation studies of pores in UO 2 [33][34][35][36][37] , they have focused on phenomena such as migration under a thermal gradient 33 , thermomechanical properties 34 , interaction of the pores with each other 38 or with grain boundaries, 35 and re-solutioning of inert gases from bubbles in the lattice 36,37 2 Computational details…”