Post Service Investigations of VVER-440 RPV Steel from NPP Greifswald

Only the investigation of reactor pressure vessel steel from operated NPPs offers the opportunity to evaluate the real toughness response of the material to neutron/ gamma radiation. By investigation of material from the formerly Greifswald NPP the evaluation of a standard VVER-440-RPV design and the assessment of the quality of the used as well prediction rules as assessment tools will be possible. The rather different states (irradiated, irradated/annealed, and irradated/annealed/reirradiated) of the RPVs are a special advantage of the four units operated in Greifswald between 1973 and 1990. The paper describes the first results of these investigations and the next steps.