Eddy current testing (ECT) is a method for the inspection of metallic parts. The probe, excited with an alternating current, induces an eddy current in the part being inspected. Any discontinuities or material property variations that change the eddy current flow in the part are detected by the probe as a potential defect.
The eddy current technique is now recognized to be fast, simple, and accurate. The technique is widely used in the aerospace, automotive, petrochemical, and power generation industries in the detection of surface or near surface defects in materials such as aluminum, stainless steel, copper, titanium, brass, In-conel, and even carbon steel (surface defect only). Very sensitive to cracks.