Abstract
It was previously reported that reduced-activation ferritic/martensitic steels (RAFs) showed a variety of changes in ductile-brittle transition temperature (DBTT) and yield stress after irradiation at 573 K up to 5 dpa. The precipitation behavior of the irradiated steels was examined and the presence of irradiation induced precipitation which works as if it was forced to reach the thermal equilibrium state at irradiation temperature 573 K. In this study, transmission electron microscopy was performed on extraction replica specimens to analyze the size distribution of precipitates. It turned out that the hardening level multiplied by the square root of the average block size showed a linear dependence on the extracted precipitate weight. This dependence suggests that the difference in irradiation hardening between RAFs was caused by different precipitation behavior on block, packet and prior austenitic grain boundaries during irradiation. The simple Hall-Petch law could be applicable for interpreting this dependence.
| Original language | English |
|---|---|
| Pages (from-to) | 42-47 |
| Number of pages | 6 |
| Journal | Journal of Nuclear Materials |
| Volume | 367-370 A |
| Issue number | SPEC. ISS. |
| DOIs | |
| State | Published - Aug 1 2007 |
Funding
This research was sponsored by the Japan Atomic Energy Agency; the Office of Fusion Energy Sciences, US Department of Energy under contract DE-ACO5-00OR22725 with UT-Battelle; and DOE/MEXT JUPITER-II Collaboration.