Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (36권1호 99-107)

The Measurement of Diffusion Coefficient of Fission Gases in Urania with Respect to O/M Ratio

화학당량에 따른 우라니아의 핵분열 기체 확산 계수 측정

김희문;박광헌;김봉구;주용선;김건식;송근우;홍권표;강영환;

경희대학교 원자력공학과;한국원자력연구소;

Abstract

The diffusion coefficient of Xe-133 was obtained from an annealing test. The specimens were made from a UO$_2$ single crystal powder with natural enrichment. Weight and grain size were 300mg and ($23mu extrm{m}$, respectively. Oxygen potentials were obtained from an oxygen sensor. Released fractions were obtained from both results of gamma scans and quantitative analysis with MCNP code, The annealing test was performed at three temperatures at once. Diffusion coefficients of Xe-133 were calculated using slope of Booth theory in each O/M ratios. Activation energy and the pre-exponential factor of the diffusion coefficient were obtained. The activation energy of near stoichiomeric $UO_2$ is 310 kJ/mol. The measured values of near stoichiometric $UO_2$ are very close to other data available. Diffusion coefficients increase with hyper-stoichiometry, due to higher concentration of cation vacancies.

Keywords

Oxygen Potential;Fission Gas;Difusion Coefficient;Annealing Test;