Atom probe tomography characterization of neutron irradiated surveillance samples from the R. E. Ginna reactor pressure vessel
Surveillance samples of a low copper (nominally 0.05 wt.% Cu) forging and a higher copper (0.23 wt.% Cu) submerged arc weld from the R. E. Ginna reactor pressure vessel have been characterized by atom probe tomography (APT) after exposure to three levels of neutron irradiation, i.e., fluences of 1.7, 3.6 and 5.8 × 10 23 n.m –2 (E > 1 MeV), and inlet temperatures of ~289 °C (~552 °F). As no copper-enriched precipitates were observed in the low copper forging, and the measured copper content in the ferrite matrix was 0.04± <0.01 at.% Cu, after neutron irradiation to a fluence of 1.7 × 10 23 n.m –3, this copper level was below the solubility limit. A number density of 2 × 10 22 m –3 of Ni–, Mn– Si-enriched precipitates with an equivalent radius of gyration of 1.7 ± 0.4 nm were detected in the sample. However, Cu-, Ni-, Mn-enriched precipitates were observed in specimens cut from different surveillance specimens from the same forging material in which the overall measured copper level was 0.08± <0.01 at.% (fluence of 3.6 × 10 23 n.m –3) and 0.09± <0.01 at.% Cu (fluence of 5.8 × 10 23 n.m –3). Therefore, these slightlymore »
- Publication Date:
- Grant/Contract Number:
- AC05-00OR22725
- Type:
- Accepted Manuscript
- Journal Name:
- Journal of Nuclear Materials
- Additional Journal Information:
- Journal Volume: 470; Journal ID: ISSN 0022-3115
- Publisher:
- Elsevier
- Research Org:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org:
- USDOE Office of Nuclear Energy (NE)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; reactor pressure vessel steel; atom probe tomography; ductile–brittle transition temperature; charpy impact energy; segregation to dislocations; weld metal; heat-affected zone
- OSTI Identifier:
- 1237628
- Alternate Identifier(s):
- OSTI ID: 1396703