Three Dimensional Modeling of Inclined Surface Cracks in FGM Coatings

2008-09-25
Kosker, S.
Dağ, Serkan
YILDIRIM, BORA
This study presents a three dimensional finite element method for mixed-mode fracture analysis of an FGM coating-bond coat-substrate structure. The FGM coating is assumed to contain an inclined semi-elliptical crack at the free surface. The trilayer structure is examined under the effect of transient thermal stresses. Strain singularity around the crack front is simulated by utilizing collapsed wedge-shaped singular elements. The modes I, II and III stress intensity factors are computed by applying the displacement correlation technique and presented as a function of time. Four different FGM coating types are examined in the parametric analyses which are metal-rich, ceramic-rich, linear variation and homogeneous coatings. The results provided illustrate the influences of the FGM coating type and crack inclination angle on the transient behavior of the mixed-mode stress intensity factors.

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Citation Formats
S. Kosker, S. Dağ, and B. YILDIRIM, “Three Dimensional Modeling of Inclined Surface Cracks in FGM Coatings,” 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38106.