Research physicist, Research Centre, Jülich,
Pages: 16 Published: Jan 1994
Reactor Pressure Vessel (RPV) steels of different chemistry and specification were irradiated in the FRJ-1 research reactor at various neutron fluences. The irradiation temperature was 288°C. The results of instrumented impact tests of normal Charpy V specimens and the results of drop-weight tests are reported. Load signals of instrumented impact tests were evaluated and the transition temperatures of the different energy fractions were compared with the related Nil Ductility Transition Temperature (NDTT) measured by the drop-weight tests. It is shown that the NDTT is coupled with the impact energy fraction describing the ductile behaviour of the impact test. NDTT and RTNDT can be evaluated from the instrumented Charpy test alone. This requires testing temperatures to be achieved at which the total impact energy does not/does contain energy of the ductility fraction — similar to the break/no break criterion of the drop-weight test.
drop-weight tests, CV impact tests, neutron fluence, irradiation of specimens, instrumented hammer, transition temperature curve
Paper ID: STP23937S