Which nondestructive testing method requires minimal preparation and detects surface or near-surface defects in metals?

Eddy current inspection is a highly effective nondestructive testing method that requires minimal preparation and is particularly adept at detecting surface or near-surface defects in conductive materials, especially metals. This technique operates based on electromagnetic induction: an alternating current is passed through a coil, creating a magnetic field that induces eddy currents in the metal being tested. Any flaws or discontinuities in the material disrupt the flow of these eddy currents, which can be measured and quantified to provide information about the integrity of the material.

The ease of setup and limited preparation required make eddy current inspection an attractive option for many applications. Unlike other methods, it does not typically require extensive surface cleaning or special environmental considerations, which can be beneficial in field settings or situations where downtime must be minimized. Additionally, it can be employed on a variety of geometries and is particularly useful for detecting cracks, corrosion, and other surface defects that are critical to the structural integrity of components. The ability to quickly evaluate a component, combined with sensitivity to small defects, underscores the method’s effectiveness in ensuring material reliability.