Design And Experiment Of Defect Recognition And Quantification Inversion System Based On ACFM Technology

Alternating current field measurement(Abbreviation ACFM)is a new non-destructive detection technology in the field of electromagnetic non-destructive detection.It can realize intelligent recognition and size quantitative inversion of metal surface and near surface cracks.It has fast detection speed,high efficiency,sensitive detection and non-contact detection and easy quantification have become a very promising electromagnetic non-destructive testing technology,which plays a very important role in the detection and evaluation of metallic materials.Research on the surface and near surface defect identification and size quantification inversion technology of the tested work-piece has always been the focus of the inspection field,which is of great significance for improving product quality and promoting safe production.In order to realize real-time intelligent identification and dimensional quantification inversion of surface defects of tested work-pieces,and improve the detection accuracy and efficiency of metal surface defects,this paper focuses on the principle of ACFM detection technology and focuses on the design of defect recognition and size quantification inversion system based on ACFM technology.The defect identification and size quantification inversion algorithm of ACFM technology was systematically studied in depth,and the defect recognition and size quantification inversion system based on ACFM technology of Java and MySQL platform was successfully designed.The main research contents are as follows:Firstly,the detection principle of ACFM technology is analyzed.According to the characteristics of ACFM technology in the detection of metal sheet defects,the theoretical model of defect calculation is obtained,which provides a theoretical basis for the qualitative and quantitative detection of surface defects.Secondly,in order to realize the real-time manual discrimination of defects,according to the hardware detection platform built by the laboratory,a stable and reliable acquisition signal is realized.The serial communication driver software is developed to complete the signal communication,and the target data is realized through the MySQL database.The extraction,storage and analysis provide an effective data source for defect identification and size quantification inversion.At thesame time,Jfrerchart is used to complete the 2D graph of target data,realizing the real-time manual discrimination of defects.Thirdly,in order to further realize the automatic identification and size quantification inversion of defects,the effects of crack length,crack depth,probe scanning mode,probe fluctuation,probe horizontal deviation distance and probe lift height on ACFM detection signals were studied.The size quantification inversion of the defect is realized according to the influence relationship between the defect size change and the ACFM detection signal.Finally,according to the influence relationship between the defect size change and the ACFM detection signal and the data collected by the database,the automatic identification and size quantification of the crack is realized by the combination of feature maximum and minimum values extraction,data model establishment and design alarm threshold.Inversion.Through the detection of different metal work-pieces,the feasibility of the intelligent identification and size quantification inversion system of ACFM technology is verified,and the detection efficiency and accuracy are improved,which has a certain driving effect on the intelligence of ACFM technology.