This thesis presents a novel procedure for representing and processing multifrequency eddy current signals. Multifrequency eddy current NDE methods are used extensively for the inspection of steam generator tubes in nuclear power plants. Existing methods utilize computationally expensive time domain procedures to process the data. The procedure outlined in the thesis uses frequency domain metho...

This paper presents a nondestructive, high frequency electromagnetic evaluation method which can be applied for the examination of periodic conductive strips or conductive fibers using the evanescent modes generated in slits or in dielectric insulation between conductive fibers. For the detection of evanescent waves we propose the use of lenses with metamaterials, both conical Swiss roll type a...

The pulsed eddy current responses to varying material thickness and conductivity are modeled using an electrical circuit ideal transformer non-linear model. The Levenberg-Marquardt algorithm is used to curve fit the experimental signal to the model. The resulting synthetic signal is examined for its ability to preserve experimental signal features such as lift-off point of intersection (LOI), a...