Which type of discontinuities can eddy current testing effectively detect?

Eddy current testing (ET) is particularly effective for detecting surface discontinuities such as cracks, which is why the identification of surface cracks is recognized as a strong capability of the technique. The eddy current method generates electrical currents that flow in response to flaws in the conductive materials through which they are induced. This interaction is enhanced when the defects are located near the surface, allowing for precise detection.

While eddy current testing has its strengths, it is less effective for revealing internal structural defects or fatigue failures that do not reach the surface. These types of discontinuities may be better suited for other nondestructive testing methods like ultrasonic testing or x-ray imaging which have greater capacity to probe beneath the surface.

Thus, the detection of surface cracks is a primary and well-established strength of eddy current testing, making it a key focus in the application of the method.