Abstract
Neutron irradiation of 7-12% Cr ferritic/martensitic steels below 425-450 °C produces microstructural defects and precipitation that cause an increase in yield stress. This irradiation hardening causes embrittlement, which is observed in a Charpy impact or fracture toughness test as an increase in the ductile-brittle transition temperature. Based on observations that show little change in strength in steels irradiated above 425-450 °C, the general conclusion has been that no embrittlement occurs above these temperatures. In a recent study of F82H steel, significant embrittlement was observed after irradiation at 500 °C, but no hardening occurred. This embrittlement is apparently due to irradiation-accelerated Laves-phase precipitation. Observations of the embrittlement of F82H in the absence of irradiation hardening have been examined and analyzed with thermal-aging studies and computational thermodynamics calculations to illuminate and understand the embrittlement during irradiation.
| Original language | English |
|---|---|
| Pages (from-to) | 191-194 |
| Number of pages | 4 |
| Journal | Journal of Nuclear Materials |
| Volume | 386-388 |
| Issue number | C |
| DOIs | |
| State | Published - Apr 30 2009 |