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Title: Evaluation of ceramic matrix composites by thermal diffusivity imaging.

Abstract

Because of the complex structural design and multiple processing steps, ceramic matrix composites (CMCs) typically contain a variety of flaws distributed throughout the volume. These flaws need to be detected and characterized because they are detrimental to CMC material properties. Thermal diffusivity imaging is a nondestructive evaluation method that can quantitatively determine the thermal property of a CMC component. Thermal diffusivity is an intrinsic material property that not only depends on the material constituents but also on the micro- and macrostructure of the CMC component. This paper investigates fundamental theories for thermal diffusivity measurement using pulsed thermal imaging from two- and one-sided setups. The variation of thermal diffusivity is examined for two types of flaws, voids and cracks, that are commonly present within CMCs. The sensitivity of thermal imaging to detect small and large flaws is analyzed and evaluated with measured thermal diffusivity data. In addition, analysis of fracture theories for the mechanical and thermal properties of materials with distributed microcracks has identified that thermal diffusivity may be used to determine the degradation of mechanical properties and, therefore, to predict the remaining life of a CMC component. Preliminary results for correlating thermal and mechanical properties are discussed.

Authors:
;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
EE
OSTI Identifier:
939068
Report Number(s):
ANL/NE/JA-57195
TRN: US200821%%137
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Int. J. Appl. Ceram. Technol.; Journal Volume: 4; Journal Issue: 1 ; 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; CERAMICS; COMPOSITE MATERIALS; DEFECTS; DETECTION; THERMAL DIFFUSIVITY; NONDESTRUCTIVE ANALYSIS; THERMODYNAMIC PROPERTIES; MECHANICAL PROPERTIES; PERFORMANCE

Citation Formats

Sun, J. G., and Nuclear Engineering Division. Evaluation of ceramic matrix composites by thermal diffusivity imaging.. United States: N. p., 2007. Web. doi:10.1111/j.1744-7402.2007.02121.x.
Sun, J. G., & Nuclear Engineering Division. Evaluation of ceramic matrix composites by thermal diffusivity imaging.. United States. doi:10.1111/j.1744-7402.2007.02121.x.
Sun, J. G., and Nuclear Engineering Division. Mon . "Evaluation of ceramic matrix composites by thermal diffusivity imaging.". United States. doi:10.1111/j.1744-7402.2007.02121.x.
@article{osti_939068,
title = {Evaluation of ceramic matrix composites by thermal diffusivity imaging.},
author = {Sun, J. G. and Nuclear Engineering Division},
abstractNote = {Because of the complex structural design and multiple processing steps, ceramic matrix composites (CMCs) typically contain a variety of flaws distributed throughout the volume. These flaws need to be detected and characterized because they are detrimental to CMC material properties. Thermal diffusivity imaging is a nondestructive evaluation method that can quantitatively determine the thermal property of a CMC component. Thermal diffusivity is an intrinsic material property that not only depends on the material constituents but also on the micro- and macrostructure of the CMC component. This paper investigates fundamental theories for thermal diffusivity measurement using pulsed thermal imaging from two- and one-sided setups. The variation of thermal diffusivity is examined for two types of flaws, voids and cracks, that are commonly present within CMCs. The sensitivity of thermal imaging to detect small and large flaws is analyzed and evaluated with measured thermal diffusivity data. In addition, analysis of fracture theories for the mechanical and thermal properties of materials with distributed microcracks has identified that thermal diffusivity may be used to determine the degradation of mechanical properties and, therefore, to predict the remaining life of a CMC component. Preliminary results for correlating thermal and mechanical properties are discussed.},
doi = {10.1111/j.1744-7402.2007.02121.x},
journal = {Int. J. Appl. Ceram. Technol.},
number = 1 ; 2007,
volume = 4,
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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