Thermal stress intensity factor evaluation for inclined cracks in functionally graded materials using Jk-integral method

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2006
Demirçivi, Bengi
The main objective of this study is to evaluate mixed mode stress intensity factors for inclined embedded cracks in functionally graded materials. Fracture analysis of inclined cracks requires the calculation of both Mode I and Mode II stress intensity factors ( I K , II K ). In this study, k J -integral is used to calculate I K and II K . Equivalent domain integral approach is utilized to evaluate the k J - integral around the crack tip. The present study aims at developing a finite element model to study inclined crack problems in graded media under thermomechanical loading. A two dimensional finite element model is developed for inclined cracks located in a functionally graded medium. Structural and thermal problems are solved using two dimensional finite elements namely 8- noded triangles. Material properties are sampled directly at the integration points of the elements, as required by the numerical integral evaluation. The main results of the study are the stress intensity factors at the crack tip for functionally graded materials subjected to thermomechanical loading.

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Citation Formats
B. Demirçivi, “Thermal stress intensity factor evaluation for inclined cracks in functionally graded materials using Jk-integral method,” M.S. - Master of Science, Middle East Technical University, 2006.