ULTRASONIC FLAW DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To achieve an accurate identification of defect echoes and surface echoes when observing a sample with a coarse surface as A scope waveform by an ultrasonic wave. SOLUTION: In this method of ultrasonic flaw detection, a transmitted wave 21 is applied repeatedly to a sample 11 such as cast material moving an ultrasonic probe 12 and a plurality of echo waves generated being reflected on the sample are detected by the ultrasonic probe. Peak values of the plurality of echo waves detected by the ultrasonic probe are converted by an A/D converter 14 into a peak data in digital values and a set of the peak data and a course data involved is stored into a memory 16 as echo data 16a per transmitted wave. The degree of variations in the course data obtained for each transmitted wave is compared with a variations reference range using an identification program to identify defect echoes and surface echoes.