Analysis of Fast Fracture of Core Region of RPV

The core region of reactor pressure vessel is the main part irradiated by the core,since irradiation raises the nil ductility transition temperature.This increases the sensibility to fast fracture.To prevent the vessel fast fracture of vessel,the fast fracture mechanics analysis is necessary in the design of reactor vessel.In the paper,fast fracture mechanics analysis was performed using the first method and the second method for RPV according to RCC-M.The analysis results met the allowable limits.