What does an increase in conductivity do to eddy current penetration?

An increase in conductivity results in deeper eddy current penetration within the material being tested. This phenomenon occurs because higher conductivity allows eddy currents to form more readily and enables them to travel further into the material before being dissipated by resistance. Essentially, as conductivity increases, the skin depth—the distance over which eddy currents can effectively penetrate—also increases. This means that in more conductive materials, the eddy currents can extend deeper compared to less conductive materials, where the currents tend to dissipate more quickly and remain confined near the surface.

Understanding this relationship is crucial in Eddy Current Testing because it influences the interpretation of test results, particularly when evaluating the integrity and thickness of materials. In practice, knowing how conductivity affects penetration helps technicians select appropriate probes and testing frequencies for accurate assessments of the materials being inspected.