摘要 : As a typical branch of active thermography techniques, eddy current pulsed thermography (ECPT) has been used to detect surface and subsurface defects in many scenarios. Among different applications, localization and characterizati... 展开 As a typical branch of active thermography techniques, eddy current pulsed thermography (ECPT) has been used to detect surface and subsurface defects in many scenarios. Among different applications, localization and characterization of rolling contact fatigue cracking (a common angular defect) in rail tracks has gained more attentions. This paper investigates three features for the inclination angle characterization of artificial angular defects. Specifically, one pixel-level and two spatial-level features, i.e., max pixel response, skewness- and kurtosis-based spatial features, are proposed to build the relations to the inclination angle. Based on the 3D FEM, the simulation results show that the relation between the max pixel response and the inclination angle is non-monotonic under different heating pulses. In contrast, the skewness- and kurtosis-based spatial features can give overall monotonic relations to the inclination angle under the condition that a longer pocket length (>= 0.38 mm) occurs and a longer heating pulse (>= 100 ms) is used. Further, the above simulation results were experimentally verified. 收起