Defect and stress non-destructive testing system and non-destructive testing method based on pulsed eddy current and Barkhausen

Abstract

The invention provides a defect and stress non-destructive detection system and non-destructive detection method based on pulsed eddy current and Barkhausen, belonging to the field of non-destructive detection. The system includes an excitation signal generator, a digital-to-analog converter, a power amplifier, an excitation coil, a Hall sensor, a signal amplification circuit, a data acquisition card and a computer. On the basis of eddy current detection, the present invention uses a mixed wave of a rectangular wave and a triangular wave as an excitation signal for ferromagnetic materials. The rectangular wave band in the first half of the mixed signal produces a pulse eddy current phenomenon, and the triangular wave band in the second half produces a Barkhausen effect. , use the signal time domain averaging method to process the signal in segments, realize the separation of the eddy current signal and the Barkhausen noise signal, and extract the feature and data processing of the signal separately, so as to realize the simultaneous online detection of the surface defects, stress and microstructure state of ferromagnetic materials , and realize the identification of hidden defects of ferromagnetic materials and the prediction of unformed defects and life. The invention can work reliably for a long time, has high sensitivity, simple method, intuitive display, high efficiency and feasibility, and the like.

Description

technical field [0001] The invention is non-destructive testing based on pulsed eddy current and stress testing of Barkhausen effect, and thus relates to the fields of non-destructive testing and mechanics. And the separation of the eddy current and the Barkhausen signal is realized according to the excitation signal, and the detection of the defect and stress of the ferromagnetic material is realized. Background technique [0002] The demand for plate-like ferromagnetic profiles is large, the production process is cumbersome, and the quality requirements for the profiles are high. Once the profiles have defects or residual stress, it will have a negative impact on the product. However, the detection of profile surface defects and stress is often done offline, which affects production efficiency and increases workload. In order to obtain the required information for complete material structure health detection and life estimation, in addition to the detection and evaluation...

AI Technical Summary

Problems solved by technology

In order to improve the efficiency of detection, however, offline manual detection is inefficient and prone to false detection and missed detection; it is cumbersome to use other sensors to detect separately, so it is necessary to design a composite detection device

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