In an impedance diagram, the solid curves represent different values of what?

In an impedance diagram used in Eddy Current Testing, the solid curves represent different values of fill factor. The fill factor is an important concept as it relates to the distribution of eddy currents in a conductive material and how they probe the material's properties.

Understanding the fill factor is crucial because it reflects how effectively the test coil's magnetic field interacts with the material being tested. A higher fill factor indicates that a larger volume of the material is influencing the impedance, providing a clearer indication of the material's condition. This relationship helps technicians assess material integrity and identify any anomalies or defects.

Options such as heat treatment, conductivity, and permeability, while related to the properties of materials and their responses in testing scenarios, do not specifically correlate with the representation provided by the solid curves on the impedance diagram in the context of Eddy Current Testing. Therefore, it is the fill factor that is accurately depicted in these solid curves, highlighting its significance in interpreting test results.