In-pile eddy current test on PWR fuel rod failed by pellet-cladding interaction.

Abstract

It is believed that pellet-cladding in-teraction (PCI) of light water reactor fuel has a potential to cause failure. To understand the PCI induced fuel failure (PCI failure), it is first necessary to understand the phenomenon of microscopic crack initiation and propagation (CIP) which initiates from the internal surfaces of Zircaloy cladding.To date, however, there have been many technical difficulties with direct CIP measurement of an irradiated fuel rod. The Halden Project has recently developed a technique with eddy-current test (ECT) which allows direct measurement of the CIP phenomenon. The use of in-pile ECT technique itself is not unique and has been used widely(1)(9).However, the application of ECT to in-pile experiments to detect CIP phenomenon leading to PCI failure, is new. This paper describes the first results of ECT on in-pile experiments carried out at the Halden Boiling Water Reactor (HBWR).