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

Title: Electrical Conductivity of 2D-SiCf/CVI-SiC

Abstract

Electrical conductivity (EC) data for several plate forms of two-dimensional, silicon carbide composite made with chemical vapor infiltration matrix and with Hi Nicalon{trademark} type S fibers (2D-SiCf/CVI-SiC) were acquired. The composite fibers were coated with pyrocarbon (PyC) of various thicknesses (50 to 310 nm) and an outer thin ({approx}60 {mu}m) SiC 'seal coat' was applied by CVD to the infiltrated plates. The EC was highly anisotropic in the transverse and in-plane directions. In-plane EC ranged from {approx}150 to 1600 S/m, increased slowly with increasing temperature, and depended primarily on the total PyC thickness. High in-plane EC-values occur because it is dominated by conduction along the numerous, continuous PyC fiber coating pathways. Transverse EC ranged from {approx}1 to 60 S/m, and increased strongly with increasing temperature up to 800 C. The transverse EC is controlled by conduction through the interconnections of the carboncoating network within and between fiber bundles, especially at moderate temperatures ({approx}300 to 700 C). Below {approx}300 C, the electrical resistance of the pure SiC seal coat becomes increasingly more important as temperatures are further lowered. Importantly, a '3-layer series' model predicts that transverse EC-values for a standard seal-coated 2DSiCf/ CVI-SiC with a monolayer PyC fiber coating of {approx}50-nmmore » thickness will be <20 S/m for all temperatures up to 800 C, as desired for a flow channel insert in a fusion reactor blanket component.« less

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1027692
Report Number(s):
PNNL-SA-82349
AT6020100; TRN: US1105259
DOE Contract Number:  
AC05-76RL01830
Resource Type:
Journal Article
Journal Name:
Fusion Science and Technology
Additional Journal Information:
Journal Volume: 60; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BREEDING BLANKETS; CHEMICAL VAPOR DEPOSITION; COATINGS; ELECTRIC CONDUCTIVITY; FIBERS; PLATES; PYROLYTIC CARBON; SILICON CARBIDES; THERMONUCLEAR REACTORS; THICKNESS

Citation Formats

Youngblood, Gerald E., Thomsen, Edwin C., and Shinavski, Robert J. Electrical Conductivity of 2D-SiCf/CVI-SiC. United States: N. p., 2011. Web.
Youngblood, Gerald E., Thomsen, Edwin C., & Shinavski, Robert J. Electrical Conductivity of 2D-SiCf/CVI-SiC. United States.
Youngblood, Gerald E., Thomsen, Edwin C., and Shinavski, Robert J. Mon . "Electrical Conductivity of 2D-SiCf/CVI-SiC". United States.
@article{osti_1027692,
title = {Electrical Conductivity of 2D-SiCf/CVI-SiC},
author = {Youngblood, Gerald E. and Thomsen, Edwin C. and Shinavski, Robert J.},
abstractNote = {Electrical conductivity (EC) data for several plate forms of two-dimensional, silicon carbide composite made with chemical vapor infiltration matrix and with Hi Nicalon{trademark} type S fibers (2D-SiCf/CVI-SiC) were acquired. The composite fibers were coated with pyrocarbon (PyC) of various thicknesses (50 to 310 nm) and an outer thin ({approx}60 {mu}m) SiC 'seal coat' was applied by CVD to the infiltrated plates. The EC was highly anisotropic in the transverse and in-plane directions. In-plane EC ranged from {approx}150 to 1600 S/m, increased slowly with increasing temperature, and depended primarily on the total PyC thickness. High in-plane EC-values occur because it is dominated by conduction along the numerous, continuous PyC fiber coating pathways. Transverse EC ranged from {approx}1 to 60 S/m, and increased strongly with increasing temperature up to 800 C. The transverse EC is controlled by conduction through the interconnections of the carboncoating network within and between fiber bundles, especially at moderate temperatures ({approx}300 to 700 C). Below {approx}300 C, the electrical resistance of the pure SiC seal coat becomes increasingly more important as temperatures are further lowered. Importantly, a '3-layer series' model predicts that transverse EC-values for a standard seal-coated 2DSiCf/ CVI-SiC with a monolayer PyC fiber coating of {approx}50-nm thickness will be <20 S/m for all temperatures up to 800 C, as desired for a flow channel insert in a fusion reactor blanket component.},
doi = {},
journal = {Fusion Science and Technology},
number = 1,
volume = 60,
place = {United States},
year = {2011},
month = {7}
}