How does surface condition affect Eddy Current Testing?

Surface condition plays a significant role in Eddy Current Testing (ECT), primarily because the interaction between the Eddy currents and the material being tested can be affected by surface characteristics. When considering rough surfaces, they can introduce variations in the electrical conductivity and permeability that may interfere with the probe's performance. These variations can lead to inconsistent Eddy current flow, making it difficult to achieve accurate measurements.

On the other hand, smooth surfaces provide a more uniform interaction for the Eddy currents, allowing for clearer detection of flaws and more accurate measurements of material properties. Therefore, a smooth surface can enhance the efficiency and reliability of ECT results.

Since both rough surfaces negatively affect probe performance and smooth surfaces help yield more accurate results, the answer that states both conditions are correct reflects the comprehensive understanding of how surface conditions impact testing outcomes.