Application Cases

Experiment Name: Research on Array Eddy Current Testing Technology

Experimental Principle:
Eddy current testing is based on the principle of electromagnetic induction and is only suitable for inspecting conductive materials. Its detection principle is as follows: when a detection coil carrying alternating current is brought close to a workpiece, eddy currents are induced in the workpiece. These eddy currents generate a magnetic field that opposes the coil’s magnetic field. This opposing field causes changes in the impedance of the detection coil, allowing information about the presence of defects in the conductor to be determined based on variations in coil impedance.

To verify the detection capability of the probe, an eddy current testing system was assembled to inspect a steel plate with a blind hole. The experiment utilized a broadband power amplifier, with the excitation sinusoidal signal set to a peak-to-peak voltage of 5 Vpp and a frequency of 600 kHz. The blind hole was inspected using three detection channels in the probe. The amplitude of the coil’s induced voltage was extracted through an effective value detection module, and changes in the signal were observed and analyzed.

Recommended Broadband Amplifier: ATA-1372A

Figure: Specifications of the ATA-1372A Broadband Amplifier