Mixed-mode stress intensity factors for an embedded crack in an orthotropic FGM coating

DAĞ S., Ilhan K. A., Erdogan F.

9th International Conference on Multiscale and Functionally Graded Materials, Hawaii, United States Of America, 15 - 18 October 2006, vol.973, pp.16-17 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 973
  • City: Hawaii
  • Country: United States Of America
  • Page Numbers: pp.16-17
  • Middle East Technical University Affiliated: Yes


Analytical and computational methods are developed to examine mixed-mode fracture behaviour of an orthotropic FGM coating bonded to a homogeneous substrate through a layer of a bond-coat. The coating is assumed to contain an embedded crack perpendicular to the direction of the material property gradation. First, an analytical solution is developed considering a perturbation problem. Using Fourier transform, the problem is reduced to a system of singular integral equations which are solved by means of an expansion-collocation technique. Then, finite element method is utilized to investigate the same problem using the displacement correlation technique (DCT). By using the developed finite element method, mixed-mode stress intensity factors are also evaluated for an FGM coating-bond coat-substrate structure that is subjected to thermal stresses.