Unveiling the feature of deposition of oxygen and water molecules on the zirconium surface: A molecular dynamic study

Abstract

Unveiling the feature of deposition of oxygen and water molecules on the zirconium surface at microscale is crucial during the initial stages of zirconium oxide layer formation in Pressurized Water Reactors (PWRs) or Light Water Reactors (LWRs). In this work, we use molecular dynamic simulations to study the feature of deposition of oxygen and water molecules on the zirconium surface. A special focus of this work is a formula our built for the number of atoms adsorbed by the metal surface at the considered moment of time. The results show that the surface density of atoms for the crystallographic plane (10-10) in is 3 times greater than that for the crystallographic plane (11-20). The effective surface density σ(10-10) for the crystallographic plane (10-10) is greater than the similar value σ(11-20) for the crystallographic plane (11-20). Furthermore, in a sufficiently wide range of temperatures, the mechanical properties of zirconium crystals during tensile deformation are practically independent of the diffusion of oxygen atoms along the grain boundaries. This distinct feature may be providing basis understanding for the experimental puzzle of oxidation rate of zirconium alloys.