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Title: Microstructural evolution of neutron-irradiated T91 and NF616 to ~4.3 dpa at 469 °C

Abstract

Ferritic-martensitic steels such as T91 and NF616 are candidate materials for several nuclear applications. Here, this study evaluates radiation resistance of T91 and NF616 by examining their microstructural evolutions and hardening after the samples were irradiated in the Advanced Test Reactor to ~4.3 displacements per atom (dpa) at an as-run temperature of 469 °C. In general, this irradiation did not result in significant difference in the radiation-induced microstructures between the two steels. Compared to NF616, T91 had a higher number density of dislocation loops and a lower level of radiation-induced segregation, together with a slightly higher radiation-hardening. Unlike dislocation loops developed in both steels, radiation-induced cavities were only observed in T91 but remained small with sub-10 nm sizes. Lastly, other than the relatively stable M 23C 6, a new phase (likely Sigma phase) was observed in T91 and radiation-enhanced MX → Z phase transformation was identified in NF616. Laves phase was not observed in the samples.

Authors:
ORCiD logo [1];  [1];  [1]; ORCiD logo [1]; ORCiD logo [2];  [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Univ. of Michigan, Ann Arbor, MI (United States)
  3. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Nuclear Science User Facility (NSUF)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1366392
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 493; Journal Issue: C; Journal ID: ISSN 0022-3115
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Tan, Lizhen, Kim, B. K., Yang, Ying, Field, Kevin G., Gray, S., and Li, M. Microstructural evolution of neutron-irradiated T91 and NF616 to ~4.3 dpa at 469 °C. United States: N. p., 2017. Web. doi:10.1016/j.jnucmat.2017.05.041.
Tan, Lizhen, Kim, B. K., Yang, Ying, Field, Kevin G., Gray, S., & Li, M. Microstructural evolution of neutron-irradiated T91 and NF616 to ~4.3 dpa at 469 °C. United States. doi:10.1016/j.jnucmat.2017.05.041.
Tan, Lizhen, Kim, B. K., Yang, Ying, Field, Kevin G., Gray, S., and Li, M. 2017. "Microstructural evolution of neutron-irradiated T91 and NF616 to ~4.3 dpa at 469 °C". United States. doi:10.1016/j.jnucmat.2017.05.041.
@article{osti_1366392,
title = {Microstructural evolution of neutron-irradiated T91 and NF616 to ~4.3 dpa at 469 °C},
author = {Tan, Lizhen and Kim, B. K. and Yang, Ying and Field, Kevin G. and Gray, S. and Li, M.},
abstractNote = {Ferritic-martensitic steels such as T91 and NF616 are candidate materials for several nuclear applications. Here, this study evaluates radiation resistance of T91 and NF616 by examining their microstructural evolutions and hardening after the samples were irradiated in the Advanced Test Reactor to ~4.3 displacements per atom (dpa) at an as-run temperature of 469 °C. In general, this irradiation did not result in significant difference in the radiation-induced microstructures between the two steels. Compared to NF616, T91 had a higher number density of dislocation loops and a lower level of radiation-induced segregation, together with a slightly higher radiation-hardening. Unlike dislocation loops developed in both steels, radiation-induced cavities were only observed in T91 but remained small with sub-10 nm sizes. Lastly, other than the relatively stable M23C6, a new phase (likely Sigma phase) was observed in T91 and radiation-enhanced MX → Z phase transformation was identified in NF616. Laves phase was not observed in the samples.},
doi = {10.1016/j.jnucmat.2017.05.041},
journal = {Journal of Nuclear Materials},
number = C,
volume = 493,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 30, 2018
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