Nachbestrahlungsausheizverfahren für Kugelbrennelemente und andere Brennstoffproben

A new equipment was installed for fission product annealing tests of spherical HTR fuel elements. An already existing high frequency furnace and two new resistance furnaces were connected with their helium sweep circuits in such an way, that at a given time the fission gas release from two of the furnaces can be monitored independently. The resistance furnaces are capable to reach temperatures of 25OO°C. The diversity of the safety design of the cooling system and an automatic temperature setting render possible long-term tests without operating personnel. Depending upon the scope, various operation sequences can be chosen. Fission gas annealing tests at irradiation temperatures to determine failure quota are normal experimental routine. High-temperature tests,however, to investigate the endurance of particles and fuel elements, the measurement of the release of solid fission products and fission gas release measurements on activated specimens are still in the status of trial