The properties of the ring and burst creep of ZIRLO cladding

Cladding is used as a separator between fuel and coolant and a container of fuel in nuclear reactors. The cladding is the first part to break in accidents like LOCA or RIA in nuclear plant. Knowledge of the fracture characteristics of cladding is indispensable for the safe operation of nuclear plants. The objective of this study is to evaluate the creep properties of nuclear cladding using the ring tensile specimen. This study consists of two parts: ring and burst creep test. From the results of the ring tensile tests arid numerical analyses, the load–displacement conversion relationship for the ring specimen (LCRR) at high temperatures was determined. LCRR was applied to obtain creep properties from ring creep tests. The results from the creep tests of ring specimens were compared with those from the burst creep tests of closed-end specimens, and the results showed an applicability of the creep test using the ring specimen instead of burst creep test for evaluating the creep properties of the cladding.