Development of Cyclic Pressurization Fatigue Test Technique for Spent Fuel Cladding Tube

If the utility adopts a load following operation, the cyclic changes of the diameter causing a low-cycle fatigue will occur more frequently. Although failures regarding a radial fatigue in the fuel cladding have not been reported yet, it is essential to accumulate a fatigue life database for use in a fuel design. Since Soniak's proposal for the low cycle radial fatigue under cyclic pressurization of the fuel cladding, KAERI's R and D group has also produced a lot of low cycle fatigue data for the un-irradiated fuel cladding tube using a cyclic pressurization device. However, fatigue data regarding irradiated fuel cladding under cyclic pressurization has not been obtained around the country until now. And the infrastructures and fatigue test techniques, which can produce the fatigue data on the irradiated fuel cladding, are still worse off. The objectives of this study are to develop a low cycle fatigue test techniques for irradiated fuel cladding, as well as to produce a stress-life curve of the irradiated cladding under the cyclic pressurization