Hostname: page-component-76fb5796d-2lccl Total loading time: 0 Render date: 2024-04-25T20:34:41.928Z Has data issue: false hasContentIssue false

Insights into Radiation Tolerance of Ceramics from Large Scale Molecular Dynamics Simulations

Published online by Cambridge University Press:  01 February 2011

Ram Devanathan
Affiliation:
ram.devanathan@pnl.gov, Pacific Northwest National Laboratory, Fundamental Science Directorate, MS K8-80, P.O. Box 999, Richland, WA, 99352, United States, 509-376-7107, 509-376-5106
William J. Weber
Affiliation:
bill.weber@pnl.gov, Pacific Northwest National Laboratory, Fundamental Science Directorate, MS K8-93, P.O. Box 999, Richland, WA, 99352, United States
Get access

Abstract

Radiation tolerant ceramics are needed to advance the utilization of nuclear energy to meet rising global energy demand. They have potential to meet the demanding radiation environments in applications as nuclear fuel and waste forms. Their discovery and development are hampered by a lack of fundamental understanding of the physics underlying radiation tolerance of ceramics. Several theories have been advanced in the literature based on structure, radius ratio of cations and ionicity or covalency of bonds. Most of these theories focus on defect production and accumulation processes only, but neglect in-cascade and thermal annihilation of defects. We have performed large scale molecular dynamics simulations of 30 keV U and Zr recoils in zircon (ZrSiO4), zirconia (ZrO2) and yttria-stabilized zirconia (YSZ) to understand the atomic-level mechanisms that contribute to radiation tolerance, particularly fast annihilation processes. Zircon is amorphized by irradiation, while zirconia and YSZ do not undergo radiation-induced amorphization. Our results reveal that dynamic defect annihilation is very effective at controlling defect accumulation in radiation tolerant materials. Based on our results, we will discuss a strategy for improving the radiation tolerance of ceramics.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)