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Title: Characterization of Phases in “Crud” from Boiling Water Reactors by Transmission Electron Microscopy

Abstract

This paper reports phases identified in samples of crud (activated corrosion products) from two commercial boilingwater reactors using transmission and analytical electron microscopy and selected-area electron diffraction. Franklinite (ZnFe2O4) was observed in both samples. Hematite (a-Fe2O3), crystalline silica (SiO2), a fine-grained mixture of iron oxides probably including magnetite (Fe3O4), hematite (a-Fe2O3), and goethite (a-FeOOH), and an unidentified high-Ba, high-S phase were observed in one of the samples. Willemite (Zn2SiO4), amorphous silica, and an unidentified iron– chromium phase were observed in the other. Chloride-bearing phases were found in both samples, and are assumed to represent sample contaminants. Because of the small sample volumes and numbers of particles studied and the possibility of contamination, it is not clear whether the differences between the phases observed in the two crud samples represent actual differences in the assemblages formed in the reactors.

Authors:
;
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - NE
OSTI Identifier:
912402
Report Number(s):
INL/JOU-06-11507
Journal ID: ISSN 0022-3115; JNUMAM; TRN: US0800374
DOE Contract Number:
DE-AC07-99ID-13727
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Nuclear Materials; Journal Volume: 362; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
21 - SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS, 36 - MATERIALS SCIENCE; BOILING; CONTAMINATION; CORROSION PRODUCTS; ELECTRON DIFFRACTION; ELECTRON MICROSCOPY; GOETHITE; HEMATITE; IRON OXIDES; MAGNETITE; MIXTURES; SILICA; TRANSMISSION ELECTRON MICROSCOPY; WATER; boiling water reactors; crud; franklinite; iron oxides; phase characterization; transmission electron microscopy; willemite

Citation Formats

Dawn E. Janney, and Douglas L. Porter. Characterization of Phases in “Crud” from Boiling Water Reactors by Transmission Electron Microscopy. United States: N. p., 2007. Web. doi:10.1016/j.jnucmat.2006.11.009.
Dawn E. Janney, & Douglas L. Porter. Characterization of Phases in “Crud” from Boiling Water Reactors by Transmission Electron Microscopy. United States. doi:10.1016/j.jnucmat.2006.11.009.
Dawn E. Janney, and Douglas L. Porter. Tue . "Characterization of Phases in “Crud” from Boiling Water Reactors by Transmission Electron Microscopy". United States. doi:10.1016/j.jnucmat.2006.11.009.
@article{osti_912402,
title = {Characterization of Phases in “Crud” from Boiling Water Reactors by Transmission Electron Microscopy},
author = {Dawn E. Janney and Douglas L. Porter},
abstractNote = {This paper reports phases identified in samples of crud (activated corrosion products) from two commercial boilingwater reactors using transmission and analytical electron microscopy and selected-area electron diffraction. Franklinite (ZnFe2O4) was observed in both samples. Hematite (a-Fe2O3), crystalline silica (SiO2), a fine-grained mixture of iron oxides probably including magnetite (Fe3O4), hematite (a-Fe2O3), and goethite (a-FeOOH), and an unidentified high-Ba, high-S phase were observed in one of the samples. Willemite (Zn2SiO4), amorphous silica, and an unidentified iron– chromium phase were observed in the other. Chloride-bearing phases were found in both samples, and are assumed to represent sample contaminants. Because of the small sample volumes and numbers of particles studied and the possibility of contamination, it is not clear whether the differences between the phases observed in the two crud samples represent actual differences in the assemblages formed in the reactors.},
doi = {10.1016/j.jnucmat.2006.11.009},
journal = {Journal of Nuclear Materials},
number = 1,
volume = 362,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • Summarizes results of two studies of "crud" at the INL. All data is from INL/EXT-06-11742 and INL/JOU-06-11507 and has been previously released for publication.
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