Study on the effect of azimuthal temperature difference on the ballooning and rupture behavior of Zircaloy-4 cladding tube under transient-heating conditions

Narukawa, Takafumi 

Laboratory-scale burst tests on non-irradiated Zircaloy-4 cladding tube specimens were performed under transient-heating conditions using an external heating method. Then the obtained data were compared to those from a previous study, where an internal heating method was used. This comparison suggests that the amount of deformation in the ballooned region may be estimated based on engineering hoop stress, azimuthal temperature difference in the cladding, and the maximum circumferential strain divided by engineering hoop stress, , which was obtained in this study, irrespective of heating method. The size of rupture opening may be affected by both the azimuthal and axial temperature differences in the cladding.