International Database on Reactor Pressure Vessel Materials for Long-Term Operation of NPPs

This paper presents the capabilities of the International Database on Reactor Pressure Vessel (RPV) Materials (the Database) for precise and comprehensive RPV lifetime assessment, aimed at supporting the long-term operation of nuclear power plants. The Database was created in the framework of the International Atomic Energy Agency activities. Fourteen countries, including the United States, France, and Russia, supplied large amounts of surveillance results and data from national and international research programs.

The recent achievements and open issues in the area of RPV radiation embrittlement assessment are considered. They concern mainly the effects resulting from long irradiation times and high neutron fluences (neutron flux influence, late blooming phases), nickel and manganese synergism, and further validation of appropriate safety concepts (the Master Curve approach).

New information from ongoing surveillance and research programs has to be incorporated into the Database for the most effective RPV radiation embrittlement prediction. These additional data will greatly support the development of embrittlement correlations and embrittlement trend curves valid for long irradiation times.