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Title: Crossover from disordered to core-shell structures of nano-oxide Y{sub 2}O{sub 3} dispersed particles in Fe

Abstract

Molecular dynamic simulations of Y{sub 2}O{sub 3} in bcc Fe and transmission electron microscopy (TEM) observations were used to understand the structure of Y{sub 2}O{sub 3} nano-clusters in an oxide dispersion strengthened steel matrix. The study showed that Y{sub 2}O{sub 3} nano-clusters below 2 nm were completely disordered. Y{sub 2}O{sub 3} nano-clusters above 2 nm, however, form a core-shell structure, with a shell thickness of 0.5–0.7 nm that is independent of nano-cluster size. Y{sub 2}O{sub 3} nano-clusters were surrounded by off-lattice Fe atoms, further increasing the stability of these nano-clusters. TEM was used to corroborate our simulation results and showed a crossover from a disordered nano-cluster to a core-shell structure.

Authors:
; ;  [1];  [1];  [2];  [3];  [4]
  1. Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)
  2. (Ministry of Education), Northeastern University, Shenyang, Liaoning 110819 (China)
  3. Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang, Liaoning 110819 (China)
  4. Department of Nuclear Engineering, Texas A&M University, College Station, Texas 77843 (United States)
Publication Date:
OSTI Identifier:
22594417
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; BCC LATTICES; COMPUTERIZED SIMULATION; DISPERSIONS; ELECTRONS; IRON; NANOSTRUCTURES; PARTICLES; SHELLS; STEELS; THICKNESS; TRANSMISSION ELECTRON MICROSCOPY; YTTRIUM OXIDES

Citation Formats

Higgins, M. P., Wang, L. M., Gao, F., E-mail: gaofeium@umich.edu, Lu, C. Y., Key Laboratory for Anisotropy and Texture of Materials, Lu, Z., and Shao, L. Crossover from disordered to core-shell structures of nano-oxide Y{sub 2}O{sub 3} dispersed particles in Fe. United States: N. p., 2016. Web. doi:10.1063/1.4959776.
Higgins, M. P., Wang, L. M., Gao, F., E-mail: gaofeium@umich.edu, Lu, C. Y., Key Laboratory for Anisotropy and Texture of Materials, Lu, Z., & Shao, L. Crossover from disordered to core-shell structures of nano-oxide Y{sub 2}O{sub 3} dispersed particles in Fe. United States. doi:10.1063/1.4959776.
Higgins, M. P., Wang, L. M., Gao, F., E-mail: gaofeium@umich.edu, Lu, C. Y., Key Laboratory for Anisotropy and Texture of Materials, Lu, Z., and Shao, L. 2016. "Crossover from disordered to core-shell structures of nano-oxide Y{sub 2}O{sub 3} dispersed particles in Fe". United States. doi:10.1063/1.4959776.
@article{osti_22594417,
title = {Crossover from disordered to core-shell structures of nano-oxide Y{sub 2}O{sub 3} dispersed particles in Fe},
author = {Higgins, M. P. and Wang, L. M. and Gao, F., E-mail: gaofeium@umich.edu and Lu, C. Y. and Key Laboratory for Anisotropy and Texture of Materials and Lu, Z. and Shao, L.},
abstractNote = {Molecular dynamic simulations of Y{sub 2}O{sub 3} in bcc Fe and transmission electron microscopy (TEM) observations were used to understand the structure of Y{sub 2}O{sub 3} nano-clusters in an oxide dispersion strengthened steel matrix. The study showed that Y{sub 2}O{sub 3} nano-clusters below 2 nm were completely disordered. Y{sub 2}O{sub 3} nano-clusters above 2 nm, however, form a core-shell structure, with a shell thickness of 0.5–0.7 nm that is independent of nano-cluster size. Y{sub 2}O{sub 3} nano-clusters were surrounded by off-lattice Fe atoms, further increasing the stability of these nano-clusters. TEM was used to corroborate our simulation results and showed a crossover from a disordered nano-cluster to a core-shell structure.},
doi = {10.1063/1.4959776},
journal = {Applied Physics Letters},
number = 3,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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