Quantitative Electromagnetic Modeling and NDE of Carbon-Carbon Composites
There is much need for investigating the use of eddy-current inspection with advanced composite materials, including graphite-epoxy and carbon-carbon. One of the problems in evaluating the performance of eddy-current inspection is that it is often difficult to characterize the conductivity of the fiber composite material. For example, when the material is composed of conducting fibers and a nonconducting matrix, as is the case with graphite-epoxy, the overall conductivity is a complicated quantity that depends on fiber conductivity, fiber density, fiber layup order (sample geometry), and the frequency at which the eddy-currents are being excited. Dependency on frequency and layup order, in particular, give the investigator much difficulty in interpreting any eddy-current data from experiments. If these two factors cause a weak effect, there may be a suitable range of frequencies for inspecting the material via application of somewhat standard techniques.
KeywordsSkin Depth Multilayer Model Bulk Model Exciting Coil Quantitative Nondestructive Evaluation
Unable to display preview. Download preview PDF.
- 1.Harold A. Sabbagh, with T. M. Roberts, J. C. Treece, and L. D. Sabbagh, “A Computational Model for Electromagnetic Interactions with Advanced Composites”, in Conference Proceedings, 4th Annual Review of Progress in Applied Computational Electromagnetics, Naval Postgraduate School, Monterey, CA, 22–24 March 1988.Google Scholar
- 2.Jeff C. Treece, Thomas M. Roberts, Denis J. Radecki, and Steven D. Schunk, “Detecting Micro-Structure and Flaws in Composites Using Eddy-Current Instrumentation,” Review of Progress in Quantitative Nondestructive Evaluation, D.O. Thompson and D.E. Chimenti eds., (Plenum, New York, 1989), volume 8.Google Scholar
- 3.H. A. Sabbagh, T. M. Roberts, and L. D. Sabbagh, “A Computational Model for Electromagnetic Interactions with Advanced Composites,” Review of Progress in Quantitative Nondestructive Evaluation, D.O. Thompson and D.E. Chimenti, eds., (Plenum: New York, 1987), volume 6A, pp. 211–215.Google Scholar