Fatigue crack growth analysis models for funcionally graded materials

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2006

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Sabuncuoğlu, Barış

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The objective of this study is to develop crack growth analysis methods for functionally graded materials under mode I cyclic loading by using finite element technique. The study starts with the analysis of test specimens which are given in ASTM standard E399. The material properties of specimens are assumed to be changing along the thickness direction according to a presumed variation function used for the modeling of functionally graded materials. The results of the study reveal the influence of different material variation functions on the crack growth behavior. In the second part, the growth of an elliptical crack which is a common case in engineering applications is analyzed. First, mode I cycling loading is applied perpendicular to the crack plane and crack growth profiles for a certain number of cycles are obtained for homogeneous materials. Then, the code is extended for the analysis functionally graded materials. The material properties are assumed to vary as an exponential function along the major or minor axis direction of the crack. The results can be used to examine the crack profile and material constants̕ influence for a certain number of cyclic loading.

Subject Keywords

Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/2/12607024/index.pdf
https://hdl.handle.net/11511/15674

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Sabuncuoğlu, “Fatigue crack growth analysis models for funcionally graded materials,” M.S. - Master of Science, Middle East Technical University, 2006.