Research On Detection Method Of Ultrasonic Scattering Imaging Based On Array Transducer

The high-speed and long-term operation of modern equipment will cause defects in the equipment,affect the operation efficiency of the equipment,and even cause safety accidents.Therefore,the internal defects of the equipment need to be detected in time.In this paper,the array transducer is applied to ultrasonic testing,the finite element simulation method is used to study the propagation characteristics of sound waves in solid media,and the delay superposition algorithm is used to locate and image the internal defects of the metal.The specific research contents are as follows:(1)The propagation characteristics of sound waves in solid media are studied,the wave equations of sound waves in solids are simply derived,and the propagation characteristics of sound waves at heterogeneous interfaces and attenuation in the medium are studied.Meta-simulation modeling and analysis laid the theoretical foundation.The commonly used methods in ultrasonic imaging detection and scattering imaging theory are introduced,which provides a theoretical basis for the imaging positioning of internal defects in the following text.(2)A defect imaging method based on array transducer and time-lapse superimposed imaging algorithm is proposed.The principle and imaging model of time-lapse overlay imaging algorithm are studied.On this basis,the finite element analysis method was used to establish a two-dimensional finite element simulation model on the defect imaging plane.The finite element post-processing module was used to analyze the propagation characteristics of acoustic waves in the metal medium at a microscopic level.Using the defect reflection simulation signal,the positioning imaging of the defect is realized by the time-lapse superimposed imaging algorithm,and the effectiveness of the imaging method is verified.At the same time,the resolution of the defect imaging by randomly selecting the excitation signals generated by different array elements and different received data amounts is analyzed.The impact of rate and sum and accuracy.(3)A defect detection experimental system was built to conduct imaging detection research on an aluminum block containing two internal defects.The array transducer is used to receive and process the scattered signals of the defects in the aluminum block,and the delay superposition algorithm is used to image the internal defects in the aluminum block.Effectiveness and accuracy of imaging of defects inside the block.