JAIPEC's R and D activity on neutron irradiation embrittlement of RPV materials

Japan Power Engineering and Inspection Corporation (JAPEIC) is managing many national RD projects in the field related to inspection, welding and integrity evaluation according to the policy of the Ministry of International Trade and Industry (MITI) on the safety and reliability of operating nuclear power plants. The Plant Life Management Technology Project (PLIM), one of these RD projects, has newly started from 1996 to develop the evaluation methodologies for the neutron irradiation embrittlement in the upper shelf region of the reactor pressure vessel (RPV) and the thermal embrittlement of duplex stainless steel components, and to develop the technology for reconstitution of RPV surveillance test pieces. For the first item of these three, the development of evaluation method in the upper shelf region, the detailed scope of test program has been recently settled and the neutron irradiation of test specimens is scheduled to start this year using the Halden Boiling Water Reactor (HBWR) in Norway. This paper presents the RD scope for the development of evaluation method for the neutron irradiation embrittlement in the upper shelf region in the PLIM project of JAPEIC (author) (ml)