Abstract
A major part of fracture mechanics is concerned with studying the initiation and propagation of fatigue cracks. This typically requires constant monitoring of crack growth during fatigue cycles and the knowledge of the precise location of the crack tip at any given time. One technique currently available for measuring fatigue crack length is the Potential Drop method [1]. The method, however, may be inaccurate if the direction of crack growth deviates considerably from what was assumed initially or the curvature of the crack becomes significant. Another popular approach is to optically view the crack using a high magnification microscope, but this entails a person constantly monitoring it. The present proposed technique uses an automated scheme, in order to eliminate the need for a person to constantly monitor the experiment. Another technique under development elsewhere is to digitize an optical image of the test specimen surface and then apply a pattern recognition algorithm to locate the crack tip.
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References
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S. Nath, R. Wincheski, J.P. Fulton and M. Namkung, “Study of the New Eddy Current Non-Destructive Testing Sensor on Ferromagnetic Materials”, To be published in the IEEE Transactions on Magnetics, November 1994.
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© 1995 Plenum Press, New York
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Nath, S., Namkung, M., Wincheski, B., Fulton, J.P. (1995). Application of Self Nulling Eddy Current Probe Technique to the Detection of Fatigue Crack Initiation and Control of Test Procedures. In: Thompson, D.O., Chimenti, D.E. (eds) Review of Progress in Quantitative Nondestructive Evaluation. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-1987-4_260
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DOI: https://doi.org/10.1007/978-1-4615-1987-4_260
Publisher Name: Springer, Boston, MA
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