Multi-layered thickness eddy current testing device based on giant magnetoresistance sensor and intelligent algorithm

Abstract

The invention discloses a multi-layered thickness eddy current testing device based on a giant magnetoresistance sensor and an intelligent algorithm. The device generates actuating signals via a signal generator, and provides the actuating signals for built-in GMR and drive coil of magnetic steel after the signals are amplified by a power amplifier. The device detects the magnitude of the eddy current signals based on the built-in GMR and the drive coil of the magnetic steel, and the signals are sent to an amplifying circuit for being amplified after being tested by a detection circuit. The output of the amplifying circuit is collected to a computer by a data acquisition circuit based on a single chip microcomputer to be processed. The signal has a close relation with the thickness of the detected multi-layered conducting materials, carries out back calculation after adopting an improved BP network and can obtain the thickness of the conducting materials of each layer. The device is applicable to the thickness testing of multi-layered conducting structure in fields of machine, printed circuit board, aerospace, national defense and the like.

Description

technical field [0001] The invention relates to a multi-layer thickness eddy current detection device based on a giant magnetoresistive sensor and an intelligent algorithm. Background technique [0002] In the fields of petroleum, chemical industry, metallurgy, shipbuilding, PCB production, aviation, aerospace and other fields, it is necessary to measure various plates and various processed parts, or to monitor various pipes and pressure vessels in production equipment, and to measure multilayer conductive materials. thickness, or to detect their thinning after being corroded during use. Therefore, thickness detection has a very broad application market. The commonly used thickness detection methods mainly include ultrasonic thickness measurement, ray thickness measurement, magnetic thickness measurement, laser thickness measurement and eddy current thickness measurement. The ultrasonic thickness measurement method is affected by factors such as the surface roughness of th...

AI Technical Summary

Problems solved by technology

However, conventional eddy current detectors use ordinary coils as the detection sensor, which can solve some problems such as single-layer thickness measurement and surface and subsurface defect detection, but it is difficult to apply to the thickness of multi-layer materials or the detection of deep defects. The main reason is that the sensitivity and spatial resolution of the coil sensor are not high enough for the thickness of multi-layer materials or deep defects

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