Ultrasonic imaging system for flaw characterization

Abstract

The ultrasonic imaging system presented here is useful for non-destructive evaluation of metal specimens. Based on the pulse-echo technique, it detects the presence, depth and shape of a flaw or discontinuity in specimens. The surface of the test specimen is scanned by an ultrasonic probe driven by a two-stepper motor assembly configured to get movements along x and y directions independently. An 8-bit microprocessor controls the stepper motors and measures the depth of the flaw at every position of the probe. The data on x and y coordinates of each probed point and depth of flaw at that point (as z coordinate) are stored in a read-write memory in real time. The recorded information is later displayed on a general-purpose CRO. In addition to the description of the system, its advantages, limitations and usage are also given in the paper. © 1992.