In a non-destructive testing context, what is the main purpose of eddy current testing?

Eddy current testing is primarily used to detect surface and near-surface flaws in conductive materials. The method works by inducing eddy currents within the test material through the use of an alternating magnetic field. When these eddy currents encounter flaws such as cracks, pits, or corrosion, the flow of the currents is disrupted, which can be detected and analyzed.

This capability makes eddy current testing particularly effective for inspecting components where surface integrity is critical, such as in aerospace and automotive applications. The response from the eddy currents can reveal information about the size and shape of any flaws present, allowing inspectors to assess the health and safety of a component without causing damage.

While other choices touch on different characteristics of materials, they do not directly align with the fundamental purpose of eddy current testing, which is aimed specifically at flaw detection rather than measuring resistance, thermal conductivity, or material density.