Mixed-mode fracture analysis of functionally graded materials under thermal stresses: A new approach using J(k)-integral

A new computational method based on the J(k)-integral is developed in order to calculate crack tip parameters for functionally graded materials (FGMs) that are subjected to mixed-mode thermal loading. By using the constitutive relations of plane thermoelasticity, J(k)-integral is modified and reduced to a domain independent form that contains area and line integrals. Temperature fields in FGMs and the components of the J(k)-integral are computed by means of the finite element method. In both thermal and mechanical analyses, finite element models are created utilizing special graded isoparametric elements that possess cubic interpolation. Numerical results are generated by considering an embedded crack under steady-state thermal stresses and periodic interface cracks subjected to thermal shock heating. The J(k)-integral approach is validated and domain independence is demonstrated by providing comparisons of the mixed-mode stress intensity factors to those calculated using an enriched finite element technique. Presented results illustrate the influences of material property gradation and crack geometry on the modes I and II stress intensity factors, energy release rate and the T-stress.


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Computation of thermal fracture parameters for orthotropic functionally graded materials using J(k)-integral
Dağ, Serkan; YILDIRIM, BORA (Elsevier BV, 2010-12-15)
This article introduces a computational method based on the J(k)-integral for mixed-mode fracture analysis of orthotropic functionally graded materials (FGMs) that are subjected to thermal stresses. The generalized definition of the J(k)-integral is recast into a domain independent form composed of line and area integrals by utilizing the constitutive relations of plane orthotropic thermoelasticity. Implementation of the domain independent Jk-integral is realized through a numerical procedure developed by m...
Dağ, Serkan; Arslan, Onur; Arman, E. Erhan (2012-01-01)
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Pnma metal hydride system LiBH: a superior topological semimetal with the coexistence of twofold and quadruple degenerate topological nodal lines
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Citation Formats
S. Dağ, “Mixed-mode fracture analysis of functionally graded materials under thermal stresses: A new approach using J(k)-integral,” JOURNAL OF THERMAL STRESSES, pp. 269–296, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35193.