Nondestructive electrical eddy current

The nondestructive electrical eddy current test is a method in which eddy current flow is induced in the test object. Changes in the flow by variations in the test specimen... 

This method is based on the principle that a mechanical force is inherently associated with flow of eddy currents. Since the eddy current field is time-variant, the mechanical force is also time-variant. Therefore, an acoustic vibration can be induced in the proper sample. To use this principle in nondestructive testing of honeycomb materials, some constituents must be electrically conductive. 

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