Coherent reconstruction of flaw images taking the effect of nonspecular reflection of ultrasonic pulses from the boundaries of a test object into account

The influence of the effect of nonspecular reflection of transverse ultrasonic waves from the boundaries of a test object on the quality of coherent images of flaws is considered. The existence of an effect of nonspecular reflection in a pulsed operating mode and the accuracy of its description within the framework of complex reflection coefficients is experimentally verified. It is shown that the effect does not influence the delay times of propagating pulses and only the amplitude of echo pulses changes. Such distortions slightly impair the quality of flaw images that are reconstructed by coherent methods. Nevertheless, the methods for eliminating the influence of this effect are considered for two methods, viz., FT-SAFT and SAFT. Images of flaws that were reconstructed by the FT-SAFT method without taking the nonspecular reflection effect and with its compensation into account are presented.