Abstract: The synthetic aperture array of ultrasonic guided waves is a important imaging method, which multi-frames imaging detection of full rank is of great significance. Aiming at the arc synthetic aperture array of ultrasonic shear horizontal (SH) guided waves in plates, the receiving aperture of arc synthetic aperture array are analyzed by using the amplitude matrix and the flight time matrix. Under the condition of transforming the transmitting array elements in turn, the multi-frames imaging of full rank and whole-frame full rank imaging of the arc synthetic aperture array are all discussed. The research results show that the multi-frames imaging of full rank of arc synthetic aperture array could be used to characterize the scattering information in the testing area, the gray value of the multi-frames images of full rank at the natural focus of arc synthetic aperture array are according with each other, and the signal-to-noise ratio of the whole-frame image of full rank is increasing. Due to the "edge effect" of the array element, the background gray value of the images corresponding to the array edge element increases by about 50%, and the contrast value of the whole-frames image of full rank increases by about 200%. The imaging detection experiment verifies the feasibility of the imaging principle, which shows that the multi-frame full rank image of arc synthetic aperture array for ultrasonic guided waves in plates could characterize the scattering information of the area to be examined, and the research work proposed would provide an important basis for the further research and application of irregular array imaging detection of ultrasonic guided waves in plates.

Key words: ultrasonic guided waves, arc synthetic aperture array, receiving matrix, multi-frames imaging detection of full rank