A Uniform Eddy Current Probe with a Double-Excitation Coil for Flaw Detection on Aluminium Plates

Abstract

In this present study, a new uniform eddy current (UEC) probe with a double-excitation coil and pancake orientation is proposed. It is confirmed that the probe generates a strong magnetic field induction that increases the intensity of uniform eddy currents; moreover, it is found to be more efficient in power consumption for excitation using a finite element simulation. Experiments are performed to detect different flaw lengths and depths on an aluminium plate. The flaw signal detected by the probe indicates a high signal-to-noise ratio and increases as a function of flaw depth. The quantitative evaluation of flaws with the proposed UEC probe is achieved based on experimental results.

Mechanism study for directivity of TR probe when applying Eddy current testing to ferro-magnetic structural materials

“…Uniform eddy current can be generated on the sample surface in the same direction as the winding of the exciting coil [3]. However, because the exciting coil is tangentially oriented, its signal is relatively weak [4]. The plus point probe comprises an exciting coil and pickup coil that are rectangular and perpendicular to each other.…”

Research on Detection Mechanism of Weld Defects of Carbon Steel Plate Based on Orthogonal Axial Eddy Current Probe

“…The above simulation analysis is based on the magnetic vector potential method. In this method, the magnetic scalar potential Ω and current vector potential T are used to represent the electromagnetic field [ 16 ]. The equation involving the method are expressed by Ampere’s law, Faraday’s law, and constitutive relation: where the various quantities are defined as : Electric field intensity (V/m) : Magnetic field intensity (A/m) : Magnetic flux density (T) : Current density (A/m 2 ) : Time (s) : Permittivity (F/m) : Magnetic permeability (H/m) : Conductivity (S/m) …”

“…The above simulation analysis is based on the magnetic vector potential method. In this method, the magnetic scalar potential Ω and current vector potential T are used to represent the electromagnetic field [16]. The equation involving the method are expressed by Ampere's law, Faraday's law, and constitutive relation:…”

“…The coil is excited by a phase difference of 90°. The probe has high sensitivity in detecting plate defects, but the detection of weld defects is not as effective as traditional UEC probe [ 16 ].…”

A sophisticated design of copper core to converge rotating eddy current control for detecting cracks in conductive materials

“…2 d). Therefore, the RUECC probe must have self-nulling and self-differential characteristics 16 , 17 to enhance the sensitivity to the highest degree and to accurately assess the physical properties of cracks, especially for small cracks. However, two crack signal peaks were evident for the small cracks in specimen 2 (Fig.…”