Research on Ultrasonic Phased Array Inspection Parameter Setting Based on 3D Imaging and Multi-signal Characterizationy

Abstract

Ultrasonic phased array has the functions of ultrasonic array, 3D imaging, and defect multi-signal characterization. However, there are problems in current detection such as effective parameter setting and inconsistent identification standards for defect characteristic signals. Based on the principle of ultrasonic phased array imaging, the experimental research on the setting of effective parameters for concrete cavity defect detection is carried out in this paper. The results show that the selection of wave velocity and frequency is the key factor to improve the accuracy of 3D imaging. For 20mm concrete cavity, when the frequency is less than 25kHz, the system cannot detect defects. When the working frequency is increased to 45KHZ, the defect imaging accuracy is gradually improved. When the frequency is increased to 60kHZ, the detection accuracy is reduced. The ultrasonic shear wave velocity is in direct proportion to the detection imaging depth. When the difference between the actual wave velocity and the set wave velocity is 10%, the influence of the detection imaging depth is small. When the difference between the actual wave velocity and the set wave velocity is greater than 20%, the detection imaging depth has a great impact, and the difference between the defect position and the actual value is too large, which may cause the system to be unable to detect the existence of defects.