skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys

Abstract

Here, the role of d electrons in determining distributions of formation and migration energies for point defects in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys (CSAs) are studied regarding electron density deformation flexibility based on first-principles calculations. The disordered state is taken into account by constructing special quasirandom structures. The migration barriers are determined by directly optimizing the saddle point. It is found that the formation energies of interstitials in CSAs are lower than those in pure Ni, whereas the formation energies of vacancies are higher. In both NiCoCr and NiCoFeCr, Co-related dumbbell interstitials exhibit lower formation energies. Notably, the distributions of migration energies for Cr interstitials and vacancies exhibit a remarkable overlap region. A detailed analysis of electronic properties reveals that the electronic charge deformation flexibility regarding e g to t 2g transition has a dominant effect on defect energetics for different elements in CSAs. Thus the electron deformation ability is suggested as a key factor in understanding the peculiar defect behavior in CSAs.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [1]; ORCiD logo [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering and Shull Wollan Center-Joint Inst. for Neutron Sciences and Dept. of Physics and Astronomy
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
OSTI Identifier:
1427635
Alternate Identifier(s):
OSTI ID: 1416068
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Materials
Additional Journal Information:
Journal Volume: 2; Journal Issue: 1; Journal ID: ISSN 2475-9953
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Defects; electronic structure; disordered alloys

Citation Formats

Zhao, Shijun, Egami, Takeshi, Stocks, G. Malcolm, and Zhang, Yanwen. Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys. United States: N. p., 2018. Web. doi:10.1103/PhysRevMaterials.2.013602.
Zhao, Shijun, Egami, Takeshi, Stocks, G. Malcolm, & Zhang, Yanwen. Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys. United States. doi:10.1103/PhysRevMaterials.2.013602.
Zhao, Shijun, Egami, Takeshi, Stocks, G. Malcolm, and Zhang, Yanwen. Mon . "Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys". United States. doi:10.1103/PhysRevMaterials.2.013602.
@article{osti_1427635,
title = {Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys},
author = {Zhao, Shijun and Egami, Takeshi and Stocks, G. Malcolm and Zhang, Yanwen},
abstractNote = {Here, the role of d electrons in determining distributions of formation and migration energies for point defects in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys (CSAs) are studied regarding electron density deformation flexibility based on first-principles calculations. The disordered state is taken into account by constructing special quasirandom structures. The migration barriers are determined by directly optimizing the saddle point. It is found that the formation energies of interstitials in CSAs are lower than those in pure Ni, whereas the formation energies of vacancies are higher. In both NiCoCr and NiCoFeCr, Co-related dumbbell interstitials exhibit lower formation energies. Notably, the distributions of migration energies for Cr interstitials and vacancies exhibit a remarkable overlap region. A detailed analysis of electronic properties reveals that the electronic charge deformation flexibility regarding eg to t2g transition has a dominant effect on defect energetics for different elements in CSAs. Thus the electron deformation ability is suggested as a key factor in understanding the peculiar defect behavior in CSAs.},
doi = {10.1103/PhysRevMaterials.2.013602},
journal = {Physical Review Materials},
number = 1,
volume = 2,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2018},
month = {Mon Jan 01 00:00:00 EST 2018}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 1, 2019
Publisher's Version of Record

Save / Share: