Research on microcracks detection of metal plate based on nonlinear ultrasound

Abstract

Abstract In recent years, phased array ultrasonic non-destructive testing technology has been increasingly applied in the field of non-destructive testing. However, current phased array ultrasonic testing is based on traditional linear ultrasound and is not sensitive to defects such as microcracks in materials. This article proposes a nonlinear ultrasonic phased array detection technology—fundamental amplitude difference. Nonlinear components are obtained by subtracting the transmission of even and odd elements from the transmission of all elements in a phased array. First, to improve the detection effect, MATLAB software is used to simulate and study probes with different parameters. Under the premise of meeting the probe design standards, the various parameters of the probes are determined. Then, an experimental model was established using the finite element tool Abaqus. The relationship between microcracks of different lengths and nonlinear components was calculated by constructing multiple microcrack damage models. The final simulation results show that as the size of microcracks increases, the corresponding nonlinear components also gradually increase, which can more accurately detect nonlinear components and improve detection accuracy.