Eddy Current Signal Calculations for Surface Breaking Cracks

Semi-Elliptical Surface Flaw EC Interaction and Inversion: Experiment

“…Following the development of the basic analysis for nonuniform probe fields [1], the first comparison of measured eddy current signals with predictions of the theory was made in 1983 [2]. The following year brought development of a full inversion procedure for rectangular flaws [3], which was successfully demonstrated using flaw signals measured for a series of rectangular electrical-discharge machined (EDM) notches in aluminum [4].…”

Assessment of the Effects of Scanning Variations and Eddy Current Probe Type on Crack Detection

“…Attention has been focused on this problem and much of the work described in this volume is directed toward the determination of critical characteristics of NDE applications and in the generation of supporting theory to facilitate predictive modeling of NDE performance capability. The experimental work described in this paper expands on previous work on the characterization of eddy current probes, as applied to flaw detection [1,2], and is directed to support the expansion of application theory [3].…”

Computation of Eddy Current Signals and Quantitative Inversion with Realistic Probe Models

“…We have performed experiments to test both the physical correctness of the theory presented in an earlier paper (Muennemann et al, 1983), referred to below as MAFP, and the usefulness which it and its extension (Auld et al, 1984a) can achieve in practice. This paper describes the "experiments performed and modifications to the earlier inversion procedure.…”

“…A more general version of Eq. (1) is described in the companion paper (Auld et al, 1984a), ~ith computed results for various probes and flaws tested in this program.…”

“…This requires extensive operator intervention, which we like to ~educe as much as possible. Also, the present programs use data at only one probe position, whereas to optimize the use of the available data, the error parameter 0 should take into account data at all probe positions since it has been shown by Auld et al, (1984a) …”