skip to main content

DOE PAGESDOE PAGES

Title: Radiation response of alloy T91 at damage levels up to 1000 peak dpa

Ferritic/martensitic alloys are required for advanced reactor components to survive 500–600 neutron-induced dpa. In this paper, ion-induced void swelling of ferritic/martensitic alloy T91 in the quenched and tempered condition has been studied using a defocused, non-rastered 3.5 MeV Fe-ion beam at 475 °C to produce damage levels up to 1000 peak displacements per atom (dpa). The high peak damage level of 1000 dpa is required to reach 500–600 dpa level due to injected interstitial suppression of void nucleation in the peak dpa region, requiring data extraction closer to the surface at lower dpa levels. At a relatively low peak damage level of 250 dpa, voids began to develop, appearing first in the near-surface region. With increasing ion fluence, swelling was observed deeper in the specimen, but remained completely suppressed in the back half of the ion range, even at 1000 peak dpa. The local differences in dpa rate in the front half of the ion range induce an “internal temperature shift” that strongly influences the onset of swelling, with shorter transient regimes resulting from lower dpa rates, in agreement not only with observations in neutron irradiation studies but also in various ion irradiations. Swelling was accompanied by radiation-induced precipitation ofmore » Cu-rich and Si, Ni, Mn-rich phases were observed by atom probe tomography, indicating concurrent microchemical evolution was in progress. Finally, in comparison to other ferritic/martensitic alloys during ion irradiation, T91 exhibits good swelling resistance with a swelling incubation period of about 400 local dpa.« less
Authors:
 [1] ;  [1] ;  [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [5] ;  [5] ;  [6] ;  [1]
  1. Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering
  2. Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering; Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  3. Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering; Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  5. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  6. Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering; Radiation Effects Consulting, Richland, WA (United States)
Publication Date:
Report Number(s):
LA-UR-18-20859
Journal ID: ISSN 0022-3115
Grant/Contract Number:
AC52-06NA25396; NE0008297
Type:
Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 482; Journal ID: ISSN 0022-3115
Publisher:
Elsevier
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Texas A & M Univ., College Station, TX (United States)
Sponsoring Org:
USDOE Office of Nuclear Energy (NE)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; void swelling; ion irradiation; T91; high dpa; depth dependence; injected interstitial suppression; microchemical evolution
OSTI Identifier:
1440448
Alternate Identifier(s):
OSTI ID: 1396825