Optimization Research on Defect Localization in Ultrasonic Images of Anisotropic and Multilayer CFRP Structures

CFRP components are highly regarded in the aviation industry due to their characteristics such as high strength and good fatigue resistance. However, due to the inherent complexity of CFRP structures, defects are inevitable during the manufacturing process. This paper addresses the challenges of rapid backpropagation of sound ray paths between two fixed points in CFRP components, considering the effects of elastic anisotropy and multilayer structure coupling. This paper proposes a sound ray tracing method based on the Dijkstra shortest path search algorithm and make improvements. The research also involves the study of ultrasonic wave propagation characteristics and experiments using bottom reflection and Total Focusing Method (TFM) imaging detection. The research results indicate that the material's anisotropy significantly affects the imaging quality, defect localization accuracy, and defect distribution range in ultrasonic array TFM detection. The optimized algorithm allows for accurate detection of hole defects in CFRP multilayer plate components, reducing the Array Performance Indicator (API) value to 0.47 and minimizing the defect localization error to less than 0.3mm.