Two approaches to the solution of problems of ultrasonic flaw metering: Analysis of a high-quality image of reflectors and correlation analysis of measured echo signals

Abstract

The problem of ultrasonic flaw metering consists in the obtainment of information on the reflector type, its dimensions, and the coordinates of its location. As the accuracy of determining the parameters of a discontinuity increases, the results of ultrasonic testing become more reliable. A highquality image of reflectors, which is reconstructed using the C-SAFT method with consideration for multiple reflections of pulses from the boundaries of a test object that makes it possible to determine the types and dimensions of reflectors, can be considered as one of the tools of flaw metering. However, the C-SAFT method disregards the features of reflections from discontinuities with nonuniform scattering indicatrices. As a development of flaw-metering methods, it is proposed to determine the parameters of a discontinuity from the results of comparison of the measured echo signals and estimated echo signals, which are calculated as functions of the discontinuity parameters. The results of using the proposed methods of ultrasonic flaw metering in numerical and model experiments, which demonstrate the working capacity of the proposed approach, are presented.