What type of materials are unsuitable for Eddy Current Testing?

Eddy Current Testing (ET) primarily relies on the interaction of a changing magnetic field with conductive materials to detect flaws, measure conductivity, or determine material properties. Non-conductive materials do not allow electric currents to flow and hence cannot effectively interact with the eddy currents generated during testing. As a result, they do not produce the necessary signals for analysis, making them unsuitable for eddy current testing.

In contrast, thin conductive materials, complex geometries, and metals with low conductivity can all still be evaluated using eddy current testing. Thin conductive materials can generate eddy currents, though the sensitivity might be affected. Complex geometries present challenges in terms of probe accessibility and signal interpretation but are not inherently unsuitable. Metals with low conductivity can also be tested, albeit with lower sensitivity, as they still allow some eddy currents to form. Therefore, non-conductive materials are the only option that definitively cannot be tested using this methodology.