摘要 |
PROBLEM TO BE SOLVED: To provide a method for ultrasonic flaw detection capable of quantitatively evaluating defects such as flaws existing in a test object even in cases where they cluster close together.SOLUTION: A method for ultrasonic flaw detection comprises the steps of: (S1) transmitting ultrasonic waves from an ultrasonic probe composed of a plurality of vibrators to at least one or more flaws existing in a test object to receive reflection waves from the test object with the ultrasonic probe; (S2) dividing evaluation regions, of regions in the test object on which ultrasonic flaw detection has been performed, into lattice-like divisions; (S3, S4, S5), for each of the divided lattices, providing gate widths for signal waveforms received by each vibrator to extract signal waveforms contained in the gate widths respectively, combining the respective extracted signal waveforms while making them match in phase, and regarding the combined signal waveforms as the signal strength of the corresponding lattice; and (S6, S7) evaluating the degree of the flaws existing in the evaluation regions, based on the signal strength of each of the lattices in the evaluation regions. |