Stress intensity factors for an interface crack between a functionally graded coating and a homogeneous substrate

Sami El-Borgi, F. Erdogan, F. Ben Hatira

Research output: Contribution to journalArticle

41 Citations (Scopus)


In this paper we consider the problem of a functionally graded coating bonded to a homogeneous substrate with a partially insulated interface crack between the two materials subject to both thermal and mechanical loading. The problem is solved under the assumption of plane strain and generalized plane stress conditions. The heat conduction and the plane elasticity equations are converted analytically into singular integral equations which are solved numerically to yield the temperature and the displacement fields in the medium as well as the crack tip stress intensity factors. A crack-closure algorithm recently developed by the authors is applied to handle the problem of having negative mode I stress intensity factors. The Finite Element Method was additionally used to model the crack problem and to compute the crack-tip stress intensity factors. The main objective of the paper is to study the effect of the material nonhomogeneity parameters, partial insulation of the crack surfaces and crack-closure on the crack tip stress intensity factors for the purpose of gaining better understanding of the thermo-mechanical behavior of graded coatings.

Original languageEnglish
Pages (from-to)139-162
Number of pages24
JournalInternational Journal of Fracture
Issue number3-4
Publication statusPublished - Oct 2003
Externally publishedYes



  • Crack-closure
  • Functionally graded coating
  • Partially insulated crack
  • Stress intensity factors

ASJC Scopus subject areas

  • Mechanics of Materials
  • Computational Mechanics

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