Nanoprecipitates to Enhance Radiation Tolerance in High-Entropy Alloys

Boopathy Kombaiah; Yufan Zhou; Ke Jin; Anus Manzoor; Jonathan D Poplawsky; Jeffery A Aguiar; Hongbin Bei; Dilpuneet S Aidhy; Philip D Edmondson; Yanwen Zhang

doi:10.1021/acsami.2c17540

Nanoprecipitates to Enhance Radiation Tolerance in High-Entropy Alloys

ACS Appl Mater Interfaces. 2023 Jan 25;15(3):3912-3924. doi: 10.1021/acsami.2c17540. Epub 2023 Jan 9.

Authors

Boopathy Kombaiah^{1

2}, Yufan Zhou¹, Ke Jin¹, Anus Manzoor³, Jonathan D Poplawsky⁴, Jeffery A Aguiar⁵, Hongbin Bei⁶, Dilpuneet S Aidhy⁷, Philip D Edmondson^{1

8}, Yanwen Zhang^{1

9}

Affiliations

¹ Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States.
² Characterization and Post-Irradiation Examination Division, Idaho National Laboratory, Idaho Falls, Idaho83415, United States.
³ Department of Mechanical Engineering, University of Wyoming, Laramie, Wyoming82071, United States.
⁴ Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States.
⁵ Nuclear Science and Technology Division, Idaho National Laboratory, Idaho Falls, Idaho83415, United States.
⁶ School of Materials Science and Engineering, Zhejiang University, Hangzhou310027, China.
⁷ Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina29634, United States.
⁸ Department of Materials, Photon Science Institute, The University of Manchester,Oxford Road, ManchesterM13 9PL, U.K.
⁹ Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee37996, United States.

PMID: 36623205
DOI: 10.1021/acsami.2c17540

Abstract

The growth of advanced energy technologies for power generation is enabled by the design, development, and integration of structural materials that can withstand extreme environments, such as high temperatures, radiation damage, and corrosion. High-entropy alloys (HEAs) are a class of structural materials in which suitable chemical elements in four or more numbers are mixed to typically produce single-phase concentrated solid solution alloys (CSAs). Many of these alloys exhibit good radiation tolerance like limited void swelling and hardening up to relatively medium radiation doses (tens of displacements per atom (dpa)); however, at higher radiation damage levels (>50 dpa), some HEAs suffer from considerable void swelling limiting their near-term acceptance for advanced nuclear reactor concepts. In this study, we developed a HEA containing a high density of Cu-rich nanoprecipitates distributed in the HEA matrix. The Cu-added HEA, NiCoFeCrCu_0.12, shows excellent void swelling resistance and negligible radiation-induced hardening upon irradiation up to high radiation doses (i.e., higher than 100 dpa). The void swelling resistance of the alloy is measured to be significantly better than NiCoFeCr CSA and austenitic stainless steels. Density functional theory simulations predict lower vacancy and interstitial formation energies at the coherent interfaces between Cu-rich nanoprecipitates and the HEA matrix. The alloy maintained a high sink strength achieved via nanoprecipitates and the coherent interface with the matrix at a high radiation dose (∼50 dpa). From our experiments and simulations, the effective recombination of radiation-produced vacancies and interstitials at the coherent interfaces of the nanoprecipitates is suggested to be the critical mechanism responsible for the radiation tolerance of the alloy. The materials design strategy based on incorporating a high density of interfaces can be applied to high-entropy alloy systems to improve their radiation tolerance.

Keywords: atom probe tomography; density functional theory; hardening; high-entropy alloys; nanoprecipitates; radiation; swelling; transmission electron microscopy.