An application of Charpy V testing: The pressure vessel surveillance program of nuclear pressurised water reactor in operation

Abstract Charpy tests are widely used in the nuclear industry in order to characterize material mechanical properties. Moreover, they are the basis for the reactor pressure vessels life evaluation through the Pressure Vessel Surveillance Program. This Program is a procedure, applied to each reactor vessel in operation in France, which allows to monitor periodically the irradiation induced material embrittlement. This paper first describes the procedure followed for the Pressure Vessel Surveillance Program. It presents the irradiation capsules: the samples materials (low alloy Mn, Ni, Mo vessel steel including base metals, heat affected zones, welds and a reference material) and the mechanical tests performed. Then it draws up a synthesis of the analysis of 177 capsules removed from reactors at fluences up to 7.10 19 n/cm 2 (E>1 MeV). This data base gathers the results of a number of Charpy tests close to 10000.