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The Estimation of Semi Elliptical Surface Cracks Advancement via Fuzzy Logic

Authors: Gürol Önal, Ahmet Avcı


This paper presented the results of an experimental investigation into the axial fatigue behavior of a 5086 aluminum alloy which have several notch-aspect ratios a0/c0 and notch thickness ratio a/t with semi-elliptical surface cracks. Tests were conducted in la b air for stress levels of 50 % of their yield strength. Experiments were carried out for various notch to thickness ratios. Crack growth rates of test specimens both in surface and depth directions were determined by using die penetration method. Fuzzy Logic method was used to predict the deep direction crack growth because the dept of the crack is considerably difficult to measure.

Keywords: crack growth rate, Al-Mg alloy, Axial fatigue, surface crack

Digital Object Identifier (DOI):

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