6. Post-irradiation techniques for examination of high temperature reactor fuel

Post irradiation examination techniques used in the Hot-Cell Laboratories at KFA Julich for the investigation of irradiated coated-particle fuel, fueled compacts and, in particular, spherical fuel elements for the German Pebble-Bed Reactors (AVR and THTR) are described. They include: measurement of dimensions, mechanical strength and fission product release, sectioning and sampling for various further examinations, selection and handling of individual coated particles and tests on single particles. This paper is intended as an Introduction to the subsequent KFA papers that will deel

in detail with special techniques.

One of the main activities of the Hot Cell-Laboratories of KFA Julich up to now has been the investigation of irradiated fuel material in the frame of the development program for the thorium high-temperature reactor (THTR). In fact, a complete cell line has been constructed for these investigations and has been operating successfully since early 1967.