What is the main advantage of using eddy current testing compared to other non-destructive testing methods?

The main advantage of using eddy current testing lies in its capability to detect surface and near-surface defects. This method utilizes electromagnetic induction to generate eddy currents in conductive materials, which are influenced by the presence of flaws. As these currents flow through the material, any discontinuities, such as cracks or corrosion occurring at or near the surface, will disrupt the flow of the eddy currents. This disruption can be easily measured and interpreted, making eddy current testing particularly effective for identifying defects that are not easily accessible or visible, especially in conductive materials.

In contrast, while other methods may excel in areas like testing thicker materials or achieving lower equipment costs, they may not provide the same level of sensitivity for detecting superficial defects. Some methods may also require direct access or involve more complex setups, making eddy current testing a preferable choice when surface integrity is crucial.