Evaluation of brittle crack arrest toughness of reactor pressure vessel steels

Tobita, Toru; Otsu, Takuyo*; Takamizawa, Hisashi ; Nishiyama, Yutaka 

When the reactor pressure vessel has been subjected to the pressurized thermal shock event, even if an non-ductile crack occurs from the postulated defect at the inner surface of the reactor pressure vessel, the crack may stop before penetrates the vessel wall. In this report, crack-arrest fracture toughness (K) tests were performed on the three types of reactor pressure vessel steels with different mechanical properties. It was confirmed that the temperature dependency of K follows the Master Curve as well as static fracture toughness. In addition, we examined the correlation between the crack-arrest fracture toughness and crack arrest force of instrumentation Charpy test.