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Title: Irradiation Creep of Chemically Vapor Deposited Silicon Carbide as Estimated by Bend Stress Relaxation Method

Abstract

The bend stress relaxation technique was applied for an irradiation creep study of high purity, chemically vapor-deposited beta-phase silicon carbide (CVD SiC) ceramic. A constant bend strain was applied to thin strip samples during neutron irradiation to fluences 0.2-4.2 dpa at various temperatures in the range {approx}400 to {approx}1080 C. Irradiation creep strain at <0.7 dpa exhibited only a weak dependence on irradiation temperature. However, the creep strain dependence on fluence was non-linear due to the early domination of the initial transient creep, and a transition in creep behavior was found between 950 and 1080 C. Steady-state irradiation creep compliances of polycrystalline CVD SiC at doses >0.7 dpa were estimated to be 2.7({+-}2.6) x 10{sup -7} and 1.5({+-}0.8) x 10{sup -6} (MPa dpa){sup -1} at {approx}600 to {approx}950 C and {approx}1080 C, respectively, whereas linear-averaged creep compliances of 1-2 x 10{sup -6} (MPa dpa){sup -1} were obtained for doses of 0.6-0.7 dpa at all temperatures. Monocrystalline 3C SiC samples exhibited significantly smaller transient creep strain and greater subsequent deformation when loaded along <0 1 1> direction.

Authors:
 [1];  [1];  [2];  [1];  [2]
  1. ORNL
  2. Kyoto University, Japan
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); High Flux Isotope Reactor
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
978263
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Nuclear Materials; Journal Volume: 367; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CREEP; DEFORMATION; IRRADIATION; NEUTRONS; SILICON CARBIDES; STRAINS; STRESS RELAXATION; TRANSIENTS

Citation Formats

Katoh, Yutai, Snead, Lance Lewis, Hinoki, Tatsuya, Kondo, Sosuke, and Kohyama, Akira. Irradiation Creep of Chemically Vapor Deposited Silicon Carbide as Estimated by Bend Stress Relaxation Method. United States: N. p., 2007. Web. doi:10.1016/j.jnucmat.2007.03.086.
Katoh, Yutai, Snead, Lance Lewis, Hinoki, Tatsuya, Kondo, Sosuke, & Kohyama, Akira. Irradiation Creep of Chemically Vapor Deposited Silicon Carbide as Estimated by Bend Stress Relaxation Method. United States. doi:10.1016/j.jnucmat.2007.03.086.
Katoh, Yutai, Snead, Lance Lewis, Hinoki, Tatsuya, Kondo, Sosuke, and Kohyama, Akira. Mon . "Irradiation Creep of Chemically Vapor Deposited Silicon Carbide as Estimated by Bend Stress Relaxation Method". United States. doi:10.1016/j.jnucmat.2007.03.086.
@article{osti_978263,
title = {Irradiation Creep of Chemically Vapor Deposited Silicon Carbide as Estimated by Bend Stress Relaxation Method},
author = {Katoh, Yutai and Snead, Lance Lewis and Hinoki, Tatsuya and Kondo, Sosuke and Kohyama, Akira},
abstractNote = {The bend stress relaxation technique was applied for an irradiation creep study of high purity, chemically vapor-deposited beta-phase silicon carbide (CVD SiC) ceramic. A constant bend strain was applied to thin strip samples during neutron irradiation to fluences 0.2-4.2 dpa at various temperatures in the range {approx}400 to {approx}1080 C. Irradiation creep strain at <0.7 dpa exhibited only a weak dependence on irradiation temperature. However, the creep strain dependence on fluence was non-linear due to the early domination of the initial transient creep, and a transition in creep behavior was found between 950 and 1080 C. Steady-state irradiation creep compliances of polycrystalline CVD SiC at doses >0.7 dpa were estimated to be 2.7({+-}2.6) x 10{sup -7} and 1.5({+-}0.8) x 10{sup -6} (MPa dpa){sup -1} at {approx}600 to {approx}950 C and {approx}1080 C, respectively, whereas linear-averaged creep compliances of 1-2 x 10{sup -6} (MPa dpa){sup -1} were obtained for doses of 0.6-0.7 dpa at all temperatures. Monocrystalline 3C SiC samples exhibited significantly smaller transient creep strain and greater subsequent deformation when loaded along <0 1 1> direction.},
doi = {10.1016/j.jnucmat.2007.03.086},
journal = {Journal of Nuclear Materials},
number = 1,
volume = 367,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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