Application of the Potential Drop Procedure for Fatigue Crack Growth
Charakterisieren des Rissausbreitungsverhaltens Anwendungen der Gleichstrom potenzialsonde im Umfeld der Ermüdungsrissausbreitung
St. Rödling, 1. Bär, H. J. Gudladt
ABSTRACT For the characterisation of the crack growth behavior the potential drop method for the permanent measurement of the crack length worked satisfactorily. Beyond that it enables the investigation of further measurands in the domain of crack growth. These continuative applications of the potential drop method on metallic materials are presented in this article. With different aluminum alloys it is to be demonstrated that in atmospheres without oxygen the investigation of the crack closure behavior is possible by hysteresis loops, which were recorded using the potential drop method. In relation to conventional crack closure measurements a distinction of different crack closure mechanisms is possible. Beyond that the influence of single overloads on crack propagation behaviour can be investigated into. For example the region with accelerated crack propagation is continuously measured with the occurrence of single overloads and allows a simple measurement of a local crack resistance curve, which permits a characterisation of the crack growth within the crack tip region.
Publication Source: Materialprüfung, ISSN: 0025-5300
Issue: 2002-11/12, pp 454-460
Publisher: Carl Hanser Verlag München
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