Fracture toughness tests using the master curve method were performed on Fe-Cr model alloys with various Cr concentrations (2.5, 5, 9 and 12 wt.%) before and after neutron-irradiation at 300 °C in BR2 to the dose of 0.6 dpa, to evaluate the irradiation embrittlement. Charpy V-notch impact tests were also performed to compare the reference temperature in master curve, T0, and DBTT-shift.
It is found that the Cr content effect on T0 is not significant for unirradiated specimens. After irradiation, T0 for Fe-2.5Cr is slightly lower than the other three alloys, thus ΔT0 is lower than the others as well. From Charpy V-notch impact tests, however, Fe-2.5Cr and Fe-9Cr exhibit the same DBTT-shift.
For Fe-2.5Cr and Fe-9Cr alloys, the correlation of ΔT0 and ΔDBTT was tstudied and compared with the results of F/M steels and ferritic RPV steels . For the Fe-9Cr alloy, ΔT0 is significantly higher than ΔDBTT. In contrast, for the Fe-2.5Cr alloy, the obtained ΔT0 and ΔDBTT are similar to each other, differently from the case of Fe-9Cr. Further studies to understand the origin of the difference between Fe-2.5Cr and Fe-9Cr alloys are necessary.
|Number of pages||38|
|State||Published - Mar 2013|
|Publisher||Studiecentrum voor Kernenergie|