ULTRASONIC FLAW DETECTION METHOD, ULTRASONIC FLAW DETECTOR, STEEL MATERIAL MANUFACTURING EQUIPMENT ROW, STEEL MATERIAL MANUFACTURING METHOD, AND STEEL MATERIAL QUALITY ASSURANCE METHOD

摘要

To provide an ultrasonic flaw detection method and an ultrasonic flaw detector capable of performing high-speed ultrasonic flaw detection with high detection capability and resolution over the entire range inside a test material.SOLUTION: An ultrasonic flaw detection method according to the present invention includes: a receiving step of a plurality of defect signals in one or more vibrating elements provided in an ultrasonic probe while changing a positional relationship between a test material and the ultrasonic probe; a determination step of determining a synthetic waveform group in an aperture synthesizing process at each vibration element position of the test material, based on a received sound pressure ratio that is calculated in each positional relationship between the test material and the vibration element, as a ratio of received sound pressure at each vibration element position to the received sound pressure at the vibration element position where the received sound pressure from the defect is maximum; an inspection step for inspecting the inside of the test material by performing the aperture synthesizing process on received waveforms obtained by multiple transmissions and receptions using the synthetic waveform group determined in the determination step and delay times of the plurality of defect signals.SELECTED DRAWING: Figure 1