Reactor pressure vessel (RPV) is an important safety component which holds reactor core and keep on high temperature and high pressure coolant. The irradiated region of RPV is subjected to neutron damage so that the fracture toughness decrease and RTNDT of materials with neutron fluence increase. According to fracture toughness requirements based on the rule, RPV beltline materials must have Charpy upper-shelf energy of no less than 102J initially and must maintain upper-shelf energy throughout the life of the vessel of no less than 68J.
Chinese manufactures (China First Heavy Industries, China National Erzhong Group Co. and Dongfang Electric Corporation, Shanghai Electric Corporation) have supplied A508-3 steel forging and fabricated RPV for many constructing NPP in China. Nuclear Power Institute of China (NPIC) has being put into practice a program about the irradiation tests and irradiation brettling research of Chinese A508-3 steel from these manufactures. This paper introduces the program and progressing briefly. Specimen, irradiation test parameters, irradiation facility and post irradiation mechanical tests are also described.