Flexible array type eddy current sensor with circular periodic structure

Abstract

The invention discloses a flexible array type eddy current sensor with a circular periodic structure. The flexible array type eddy current sensor comprises four layers of structures, wherein the top layer and the bottom layer are excitation coils, and the two middle layers are detection coil arrays; the excitation coils are periodically circular closed-loop coils formed by routing upper and lower staggered semicircular periodic coils; the detection coil arrays comprise a plurality of detection coils; the detection coils adopt double-layer spiral structures; the upper layer of the detection coils and the lower layer of the detection coils are conducted through penetrating holes; the spiral winding directions of the upper layer of the detection coils and the lower layer of the detection coils are opposite. The flexible array type eddy current sensor with the circular periodic structure has the advantages of simple structure, convenience in manufacturing, high space resolution, full coverage (no scanning dead corner), high output signal, high tiny defect detection capacity, high detection efficiency and the like.

Description

technical field [0001] The invention mainly relates to the technical field of non-destructive testing, in particular to an array type eddy current sensor made on a flexible substrate based on the principle of eddy current. Background technique [0002] With the development of science and technology, the scope of application of non-destructive testing technology continues to expand. It is not only the basis of modern industrial technology, but also a key technology in aerospace, national defense and military fields. It is used in machinery, construction, metallurgy, electric power, petroleum, shipbuilding, automobile , aerospace, nuclear energy, railway and other industries are widely used. Among them, "eddy current non-destructive testing technology" is a non-destructive testing method based on the principle of electromagnetic induction. It has the advantages of fast sensor response, high sensitivity, non-contact, and no coupling medium. one of the effective methods. [00...

AI Technical Summary

Problems solved by technology

[0003] However, traditional eddy current sensors generally have the following problems: ①The consistency of the sensor is poor, the detection signal is easily affected by factors such as lift-off, and the quantitative detection effect is poor; ②There is a contradiction between detection efficiency and detection resolution, and it is difficult to achieve rapid detection; ③ It can only detect existing defects, but cannot monitor the stress distribution in the material and the development process of fatigue damage; ④ Poor adaptability to the detection object, and the false detection rate of complex structures is high

Although this type of planar eddy current sensor can effectively improve the common shortcomings of traditional eddy current sensors, it also has the following shortcomings: it can only detect defects in a specific direction, the detection efficiency is low, and there are gaps between detection units, which are prone to Missed detection, and the detection unit is not only small in size, but the single-turn coil is used as the detection unit, the output signal is too weak, which is not conducive to the back-end signal processing

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