Eddy current inspection can be used in conjunction with other inspection methods for specific applications. For example, the Phoenix ISL TSIS solution incorporates both ultrasonic and eddy current techniques simultaneously for volumetric and surface inspections.
Eddy current Testing (ECT) provides a fast efficient solution for near-surface anomalies, such as crack detection, in conductive material. Often, defects sit just below the surface of the inspection material or paint and other coatings applied to outer surface cover the anomalies.
ECT is based on the physics phenomenon of electromagnetic induction. In an eddy current probe, alternating currents flow through a wire coil and generate an oscillating magnetic field. The magnetic field from the coil is induced into the component to be inspected and any anomalies in the material create changes to the “eddy currents” or phase and amplitude of the measured signal which are displayed on an eddy current flaw detector as a distinct change in signal.
Eddy current NDT inspection can be used across a wide range of industries including:
Advantages of Eddy Current Inspection Method
- Faster scanning speed than conventional ultrasonic testing (UT)
- Crack detection on or near the inspection surface
- Requires no fluid couplant (unlike conventional UT)
- Inspection surfaces need minimal preparation
- Eddy current probes do not have to be in contact with the inspection surface
- Eddy current signals penetrate through paint and coatings to provide results
- Complex geometries can be investigated
- Provides instant results with imaging systems
The Phoenix ISL TSIS solution uses multi-element transducers with two arrays, each fitted with up to four elements. A typical configuration uses four single-element ultrasonic probes, one twin ultrasonic probe and an eddy current array probe.