ABSTRACT
Rolling contact fatigue (RCF) cracks online detection using eddy current testing (ECT) is in urgent demand. However, RCF cracks detection and evaluation in this way under moving conditions remains challenging due to the velocity effect in ECT. This paper aims to study the response of a transmitter-receiver eddy current probe to cracks under moving conditions and evaluate the depth and inclination angle of RCF cracks. In this paper, a high-speed eddy current testing system is developed to experimentally investigate the influence of coil gap, detection speed, and the lift-off on the eddy current probe’s response under moving conditions. In addition, the temporal and amplitude features of the eddy current signal are extracted to characterise the depth and inclination angle of the RCF cracks. The experimental results indicate the eddy current probe’s response can be improved by increasing the coil gap (coil centre distance) suitably, which can be done to compensate for the attenuation of the eddy current signal caused by detection speed and lift-off. The probe’s response hardly changes with an increase in detection speed when the driver and pick-up coils of the eddy current probe completely overlap. The crack depth and inclination angle can be evaluated under moving conditions.
Acknowledgments
This work is supported by the National Natural Science Foundation of China under Grant 61903193, the China Postdoctoral Science Foundation under Grant 2020M671476, Natural Science Foundation of China (Grant No. U1931126), International collaboration and exchange project of NSFC (Grant No. 6196020601), and International Science and Technology Innovation Cooperation Project of Sichuan Province, China (Grant No. 2021YFH0036).
Disclosure statement
No potential conflict of interest was reported by the authors.