The thesis addresses a method for non-destructive testing of ferromagnetic materials with an eddy current probe. Theoretical background of magnetic particles, ultrasonic and eddy current testing are discussed, as well as necessary equipment for performing each examination. Besides testing of material for irregularities, other possible applications of presented methods are also commented.
Procedure of constructing the probe for examination of materials with eddy currents through simulations is presented. Simulations were made on multiple simulation models. Different probes were compared with presented criteria. All probe's geometrical parameters, which affect on probability of detecting irregularities, were evaluated and discussed.
Besides the practical version of the probe, a constant sine current source and electrical circuits for sampling of the exciting current and detection voltage were constructed. An user interface for controlling the examination procedure was developed. The program also processes acquired electrical signals and presents them graphically to the operator.
Successful detection of irregularities in cast iron brake disc was confirmed through simulations. The same irregularities as in simulations were tested with the developed probe. Comparison between simulation and measurement results was conducted and some further improvements of measuring systems were proposed.
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