A method for inspecting a part is provided. The method includes applying a
number of multifrequency excitation signals to a probe to generate a
number of multifrequency response signals for the part being inspected.
The method further includes performing a multifrequency phase analysis on
the multifrequency response signals to inspect a subsurface of the part.
An inspection system is provided and includes an eddy current (EC) probe
configured to induce eddy currents in a part. The system further includes
an eddy current instrument coupled to the EC probe and configured to
apply multifrequency excitation signals to the EC probe to generate
multifrequency response signals. The system further includes a processor
configured to analyze the multifrequency response signals from the EC
instrument by performing a multifrequency phase analysis, to inspect a
subsurface of the part.