Ultrasonic characterization of crack-like defects using scattering matrix similarity metrics

Crack-like defects form an important type of target defect in nondestructive evaluation, and accurately characterizing them remains a challenge, particularly for small cracks and inclined cracks. In this paper, scattering matrices are used for defect characterization through use of the correlation coefficient and the structural similarity (SSIM) index as similarity metrics. A set of reference cracks that have different lengths and orientation...