Effect of Single and Multi-Direction Coil for Differential Probe on Depth Crack Defect Measurement with Different Excitation Frequency Selection in Eddy Current Inspection

Abstract In recent years, a number of studies in Non-Destructive Evaluation (NDE) have been conducted on the sensitivity probes assessing depth cracks based input stimulation. Range frequency and crack suggested as relevant features for excitation waveform forms. The construction an encircling coil differential probe (ECDP) absolute (ECAP) was discussed this paper. For defect, Multi-Frequency (MF) measuring method used to compare ECDP with single direction multi-direction turn growth. measurement coupling ECAP. By comparing resulting signal between probes, it is clear that (with longitudinal transverse coils) very effective various types defects ranges. ideal frequencies inspection testing are 30kHz 60kHz.