Friction damage assessment on cylindrical Cr-Mo steel using evaluation parameters by various types of eddy current sensors

This study proposes a system for assessing surface damage on cylindrical Cr-Mo steel using eddy current testing (ECT) with film EC, and T-shaped probes designed to conform to curved surfaces for improved contact and measurement stability. By applying a normalised impedance curve to eliminate probe geometry influence and highlight electromagnetic changes caused by damage, the study uses both conventional and modified parameters, with the latter enhancing the inductive component’s contribution and yielding clearer separation between damage levels, especially at early-stages. The percentage relative changes analysis shows higher sensitivity across all probe types with the modified parameter, and experimental and simulation results confirm that probe configuration and analysis methods are crucial for improving damage detection efficiency.