Abstract
A specific phenomenon - highly localized regions of deformation - was found and investigated at the free surface and near-surface layer of a neutron irradiated AISI 304 stainless steel bend specimen deformed to a maximum surface strain of 0.8%. It was shown that local plastic deformation near the surface might reach significant levels being localized at specific spots even when the maximum free surface strain remains below 1%. The effect was not observed in non-irradiated steel of the same composition at similar strain levels. Cross-sectional EBSD analysis demonstrated that the local misorientation level was highest near the free surface and diminished with increasing depth in these regions. (S)TEM indicated that the local density of dislocation channels might vary up to an order of magnitude. These channels may contain twins or may be twin free depending on grain orientation and local strain levels. BCC-phase (α-martensite) formation associated with channel-grain boundary intersection points was observed using EBSD and STEM in the near-surface layer.
| Original language | English |
|---|---|
| Pages (from-to) | 500-508 |
| Number of pages | 9 |
| Journal | Journal of Nuclear Materials |
| Volume | 452 |
| Issue number | 1-3 |
| DOIs | |
| State | Published - Sep 2014 |
Funding
This research was sponsored by the U.S. Department of Energy, Office of Nuclear Energy, for the Light Water Reactor Sustainability Research and Development Effort, and the SHaRE User Facility, sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, and the U.S. Department of Energy. The authors would like to thank Dr. C.M. Parish and Dr. T.S. Byun from Oak Ridge National Laboratory (ORNL) for their fruitful discussions on the results and D.P. Stevens (ORNL) for assisting in preparations of this manuscript. This manuscript has been authored by the Oak Ridge National Laboratory, managed by UT-Battelle LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes.
| Funders | Funder number |
|---|---|
| Light Water Reactor Sustainability Research and Development Effort | |
| Office of Basic Energy Sciences | |
| Scientific User Facilities Division | |
| UT-Battelle LLC | |
| U.S. Department of Energy | |
| Office of Nuclear Energy |