Fission product release and microstructure changes of irradiated MOX fuel at high temperatures

Samples of irradiated MOX of 44 GWd/tHM mean burn-up were prepared by core drilling at three different radial positions of a fuel pellet. They were subsequently heated in a Knudsen effusion mass spectrometry system up to complete vaporization of the sample (~2600 K) and the release of fission gas (krypton and xenon) and helium was measured. Scanning electron microscopy was used in parallel to investigate the evolution of the microstructure of a sample heated in the same condition up to given key temperatures as determined from the gas release profiles. A clear difference for fission gas release and microstructure was observed as a function of the radial position of the samples and therefore of irradiation temperature. A good correlation between the microstructure evolution and the gas release could be established as a function of the temperature of irradiation and (laboratory) heating.

HIERNAUT Jean-Pol;  WISS Thierry;  COLLE Jean-Yves;  BENES Ondrej;  THIELE Hartmut;  PAPAIOANNOU Dimitrios;  RONDINELLA Vincenzo;  SASAHARA Akihiro;  SONODA T.;  KONINGS Rudy; 

2013-10-11

ELSEVIER SCIENCE BV

JRC81665

0022-3115,   

http://www.sciencedirect.com/science/article/pii/S0022311513010970,    https://publications.jrc.ec.europa.eu/repository/handle/JRC81665,   

10.1016/j.jnucmat.2013.09.022,