Abstract: A method for reconstructing the crack profiles based on the composite-mode total focusing method (CTFM), including: selecting the parameters for phased array ultrasonic testing; acquiring the A-scan signal matrix; establishing the coordinate system and grid division of the region of interest (ROI); determining the wave modes; solving the positions of the refracted points; reconstructing the image by CTFM; and realizing the quantification, positioning, and orientation of cracks. The A-scan signal matrix including 21 views is acquired. Based on Fermat's principle, the refracted points at the interface between wedge and sample for the 21 views are calculated, to obtain the corresponding amplitude for each view in the ROI. For each reconstruction point, the strongest response is selected from the 21 views. The profiles of the cracks with different orientation angles are reconstructed by CTFM.

Abstract: A multi-material inspection system and velocity measurement method of critically refracted longitudinal wave based on single-angle wedges belong to the field of nondestructive testing of high-end equipment. The method includes the following steps: designing a transmitting wedge and a receiving wedge with the same inclination angle, and building phased array ultrasonic-based inspection systems of critically refracted longitudinal wave; estimating a longitudinal wave velocity range of a material to be tested, calculating and optimizing a phased array ultrasonic delay law, and building a relation between a longitudinal wave velocity and an amplitude of critically refracted longitudinal wave; reading and interpolating the arrival time of a received signal, and calculating a longitudinal wave velocity of the material to be tested; determining an optimal delay law, and exciting and receiving a critically refracted longitudinal wave.

Abstract: A multi-material inspection system and velocity measurement method of critically refracted longitudinal wave based on single-angle wedges belong to the field of nondestructive testing of high-end equipment. The method includes the following steps: designing a transmitting wedge and a receiving wedge with the same inclination angle, and building phased array ultrasonic-based inspection systems of critically refracted longitudinal wave; estimating a longitudinal wave velocity range of a material to be tested, calculating and optimizing a phased array ultrasonic delay law, and building a relation between a longitudinal wave velocity and an amplitude of critically refracted longitudinal wave; reading and interpolating the arrival time of a received signal, and calculating a longitudinal wave velocity of the material to be tested; determining an optimal delay law, and exciting and receiving a critically refracted longitudinal wave.

Abstract: A method for reconstructing the crack profiles based on the composite-mode total focusing method (CTFM), including: selecting the parameters for phased array ultrasonic testing; acquiring the A-scan signal matrix; establishing the coordinate system and grid division of the region of interest (ROI); determining the wave modes; solving the positions of the refracted points; reconstructing the image by CTFM; and realizing the quantification, positioning, and orientation of cracks. The A-scan signal matrix including 21 views is acquired. Based on Fermat's principle, the refracted points at the interface between wedge and sample for the 21 views are calculated, to obtain the corresponding amplitude for each view in the ROI. For each reconstruction point, the strongest response is selected from the 21 views. The profiles of the cracks with different orientation angles are reconstructed by CTFM.