Development of a computer program for the analysis of fatigue crack growth

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2002
Dalgıç, Ali Murtaza
In this study, a computer program is developed for fatigue crack propagation analysis of metal alloys and random fiber composites. The developed program takes the fatigue crack propagation experiment data in the form of crack length vs. number of cycles from the user. The user also, selects the crack geometry and defines loading conditions of the test specimen. Developed program analyze the experimental data and evaluates crack growth rate and stress intensity range. For the calculated or ready crack growth rate data, computer program evaluates the fatigue crack growth rate dependence of stress intensity range. For this purpose computer program uses Paris Model for metal alloys and Modified Paris Model for random fiber composites. In logarithmic scale best line curve fit is done to the crack growth rate data and power law constants are calculated for the Paris and Modified Paris Models. Evaluated power law constants are used for the life estimation with Paris and Modified Paris Models. All entered and evaluated data are shown in graphical and tabular form. These values are stored for further applications.

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Citation Formats
A. M. Dalgıç, “Development of a computer program for the analysis of fatigue crack growth,” Middle East Technical University, 2002.