抄録
High-temperature plants, such as nuclear and thermal power plants are used under severe conditions. High temperature plants are susceptible to micro-cracks in its structure. This is because there is the effect of cyclic fatigue and creep fatigue. To prevent serious accidents, including small defects in the structure, we predicted the destruction, we must use safely. In particular, the evaluation of fatigue crack development is important. And, it is desirable to develop a more accurate assessment method. In this study, fatigue tests conducted for SUS304 which is often used in high temperature plant. Then observe the behavior of crack development, we examined the relationship between crack growth rate and the elastic-plastic fracture mechanics parameter, J-integral. In addition, the model plate with central crack, the J-integral analysis was performed by the virtual crack extension method.