Challenging Embrittlement Trend Curves with Lower-Than-Usual Irradiation Temperature Data

A series of irradiation-induced embrittlement trend curves was developed in the last decades and gathered in an Excel spreadsheet called PLOTTER to compare the various predicted values with the experimental data. A number of reactor pressure vessel materials, including forgings, plates, and welds with a variety of chemical compositions, were irradiated in the BR2 reactor to a neutron fluence ranging from 3 to 91019 n/cm2, E >1 MeV at lower-than-usual irradiation temperatures (100 and 150C) complemented with medium- to hightemperature irradiation data (260, 290, and 305C) for comparison. Charpy impact tests were performed to determine the ductile-to-brittle transition temperature and the upper-shelf energy level. In addition, some tensile tests were also performed to determine the irradiation-induced hardening. Test results in terms of irradiation-induced hardening and embrittlement were determined and compared with the different embrittlement trend curve predictions. The results are discussed in the perspective of assessing the performances of the various embrittlement trend curves.