Signal Evaluation System of Flexible Array Ect Probes for Inspecting Complexly Shaped Surfaces

Abstract

Articles you may be interested inDevelopment of flexible array eddy current probes for complex geometries and inspection of magnetic parts using magnetic sensors AIP Conf.ABSTRACT. We developed a signal evaluation system of flexible array eddy current testing (ECT) probes for inspecting complexly shaped metal surfaces. Our probes employ excitation and pickup coil pairs arrayed on a bendable substrate to measure curved targets. Since the developed probes produce signals due to the change in the relative position between the coil pair, an evaluation module for flaw signal identification is integrated into the system. The identification utilizes signal phase combination of the coil pairs. It is represented as a two-dimensional diagram constituting the phase values of two of the coil pairs with different positions. The phase of signals around flaws is significantly affected by their orientations. The diagram is therefore capable of separating flaw information from other information and of imaging flaw positions. We applied the system to complex geometric mock-ups. Flaw signals were successfully identified and the images obtained for identified positions could be used to efficiently measure the length of surface flaws by the 12 decibel down method.

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

“…Nishimizu [11,12] detected cracks in a non-ferromagnetic material using an arrayed multi-coil probe with two scanning angles and demonstrated that the sensitivity was affected by the two angles. Mohseni [13] investigated the scanning angle for a ferromagnetic material with a split D-probe and found that the signal amplitude varied with the scanning angle.…”

Fatigue Crack Length Sizing Using a Novel Flexible Eddy Current Sensor Array

“…Although single element eddy current sensors and multi-element sensor arrays are both used for defect sizing, sensor arrays are more widely used because of their advantages such as higher detection efficiency and spatial resolution, and larger coverage [ 8 , 12 ]. Transmit/receive (T/R) type coil configurations have been proven to provide higher detection sensitivity and better signal-to-noise ratio, and thus have been widely used in eddy current sensors [ 16 ].…”

“…The probe was very sensitive to micro-defects, yet no quantitative detection results were disclosed. Endo, et al [ 12 ] designed a flexible array eddy current testing (ECT) probe, and a 12 decibel drop method was used to size fatigue crack length, with a sizing accuracy within ±3 mm.…”

America Makes: National Additive Manufacturing Innovation Institute (NAMII) Project 1: Nondestructive Evaluation (NDE) of Complex Metallic Additive Manufactured (AM) Structures

“…Further research in EC sensors led to development of flexible AEC [66][67][68] techniques where the array conforms to the inspected surface, improving the reliability and detection capabilities of the examination. The coils can be printed or etched on a substrate with diameters of approximately 1 mm or smaller.…”