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Title: Recent Advances in Modeling Stress Distributions in Multilayers Subjected to Biaxial Flexure Tests

Abstract

Although biaxial flexure tests have been used extensively to measure the strength of brittle materials, the tests and analyses have been limited to materials of uniform properties. Despite the increasing applications of multilayered structures, characterization of their strengths using biaxial flexure tests has been difficult because the analytical description of the strength-fracture load relation for multilayers subjected to biaxial flexure tests is unavailable. The newly derived closed-form solutions for the elastic stress distributions in multilayered discs subjected to ring-on-ring tests are summarized here. These solutions are obtained by (i) finding the correlation between monolayered and multilayered discs subjected to biaxial bending moment and (ii) conversion from the existing solutions for monolayers. Using this methodology, the closed-form solutions for multilayers subjected to other biaxial flexure tests can also be obtained. Finite element results for ring-on-rings tests performed on (i) porcelain/zirconia bilayered discs and (ii) solid oxide fuel cells trilayered discs are also presented to validate the closed-form solutions. The closed-form solutions hence provide a basis for evaluating biaxial strength of multilayers using biaxial flexure tests.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
OSTI Identifier:
978025
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Composites Science and Technology; Journal Volume: 67; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
30 DIRECT ENERGY CONVERSION; BENDING; SIMULATION; SOLID OXIDE FUEL CELLS

Citation Formats

Hsueh, Chun-Hway, and Luttrell, Claire Roberta. Recent Advances in Modeling Stress Distributions in Multilayers Subjected to Biaxial Flexure Tests. United States: N. p., 2007. Web. doi:10.1016/j.compscitech.2006.08.003.
Hsueh, Chun-Hway, & Luttrell, Claire Roberta. Recent Advances in Modeling Stress Distributions in Multilayers Subjected to Biaxial Flexure Tests. United States. doi:10.1016/j.compscitech.2006.08.003.
Hsueh, Chun-Hway, and Luttrell, Claire Roberta. Mon . "Recent Advances in Modeling Stress Distributions in Multilayers Subjected to Biaxial Flexure Tests". United States. doi:10.1016/j.compscitech.2006.08.003.
@article{osti_978025,
title = {Recent Advances in Modeling Stress Distributions in Multilayers Subjected to Biaxial Flexure Tests},
author = {Hsueh, Chun-Hway and Luttrell, Claire Roberta},
abstractNote = {Although biaxial flexure tests have been used extensively to measure the strength of brittle materials, the tests and analyses have been limited to materials of uniform properties. Despite the increasing applications of multilayered structures, characterization of their strengths using biaxial flexure tests has been difficult because the analytical description of the strength-fracture load relation for multilayers subjected to biaxial flexure tests is unavailable. The newly derived closed-form solutions for the elastic stress distributions in multilayered discs subjected to ring-on-ring tests are summarized here. These solutions are obtained by (i) finding the correlation between monolayered and multilayered discs subjected to biaxial bending moment and (ii) conversion from the existing solutions for monolayers. Using this methodology, the closed-form solutions for multilayers subjected to other biaxial flexure tests can also be obtained. Finite element results for ring-on-rings tests performed on (i) porcelain/zirconia bilayered discs and (ii) solid oxide fuel cells trilayered discs are also presented to validate the closed-form solutions. The closed-form solutions hence provide a basis for evaluating biaxial strength of multilayers using biaxial flexure tests.},
doi = {10.1016/j.compscitech.2006.08.003},
journal = {Composites Science and Technology},
number = 2,
volume = 67,
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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