Abstract
The effects of irradiation on the Charpy impact properties of reduced-activation ferritic/martensitic steels were investigated on a microstructural basis. It was previously reported that the ductile-brittle transition temperature (DBTT) of F82H-IEA and its heat treatment variant increased by about 130 K after irradiation at 573 K up to 5 dpa. Moreover, the shifts in ORNL9Cr-2WVTa and JLF-1 steels were much smaller, and the differences could not be interpreted as an effect of irradiation hardening. The precipitation behavior of the irradiated steels was examined by weight analysis and X-ray diffraction analysis on extraction residues, and SEM/EDS analysis was performed on extraction replica samples and fracture surfaces. These analyses suggested that the difference in the extent of DBTT shift could be explained by (1) smaller irradiation hardening at low test temperatures caused by irradiation-induced lath structure recovery (in JLF-1), and (2) the fracture stress increase caused by the irradiation-induced over-solution of Ta (in ORNL9Cr-2WVTa).
Original language | English |
---|---|
Pages (from-to) | 283-288 |
Number of pages | 6 |
Journal | Journal of Nuclear Materials |
Volume | 329-333 |
Issue number | 1-3 PART A |
DOIs | |
State | Published - Aug 1 2004 |
Event | Proceedings of the 11th Conference on Fusion Research - Kyoto, Japan Duration: Dec 7 2003 → Dec 12 2003 |
Funding
The authors would like to thank Mr J.L. Bailey and J.W. Jones for their help on establishing the procedure for making extraction residue, and to Dr E.A. Payzant for carrying out XRD analysis. This research was sponsored by the Japan Atomic Energy Research Institute and the Office of Fusion Energy Sciences, US Department of Energy under contract DE-ACO5-00OR22725 with UT-Battelle.