Effect of Radiation Defects on Thermo–Mechanical Properties of UO<sub>2</sub> Investigated by Molecular Dynamics Method
Ziqiang Wang,
Miaosen Yu,
Chen Yang,
Xuehao Long,
Ning Gao,
Zhongwen Yao,
Limin Dong,
Xuelin Wang
Affiliations
Ziqiang Wang
Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China
Miaosen Yu
Institute of Frontier and Interdisciplinary Science, Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao 266237, China
Chen Yang
Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China
Xuehao Long
Institute of Frontier and Interdisciplinary Science, Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao 266237, China
Ning Gao
Institute of Frontier and Interdisciplinary Science, Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao 266237, China
Zhongwen Yao
Department of Mechanical and Materials Engineering, Queen’s University, Kingston, ON K7L3N6, Canada
Limin Dong
School of Materials Science and Chemical Engineering, Harbin University of Science and Technology, Harbin 150080, China
Xuelin Wang
Institute of Frontier and Interdisciplinary Science, Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao 266237, China
Nuclear fuel performance is deteriorated due to radiation defects. Therefore, to investigate the effect of irradiation-induced defects on nuclear fuel properties is essential. In this work, the influence of radiation defects on the thermo-mechanical properties of UO2 within 600–1500 K has been studied using the molecular dynamics method. Two types of point defects have been investigated in the present work: Frenkel pairs and antisites with concentrations of 0 to 5%. The results indicate that these point defects reduce the thermal expansion coefficient (α) at all studied temperatures. The elastic modulus at finite temperatures decreases linearly with the increase in concentration of Frenkel defects and antisites. The extent of reduction (R) in elastic modulus due to two different defects follows the trend Rf > Ra for all studied defect concentrations. All these results indicate that Frenkel pairs and antisite defects could degrade the performance of UO2 and should be seriously considered for estimation of radiation damage in nuclear fuels used in nuclear reactors.
