| 摘要 |
PURPOSE:To evaluate defects with high accuracy by detecting the magnitude and frequency of the transmission current in the stage of signal transmission and adding a predetermined correction value thereto. CONSTITUTION:When ultrasonic waves are transmitted by closing a switch 44 in accordance with the control signal (a) of a deciding device 13, the ultrasonic wave signal Ei passed through a material 9 to be inspected with a signal receiving coil 8 is amplified with an amplifier 12, and is quantized and stored by a memory 19. At the same time, a transmission current 14 is detected with a current probe 16, and a frequency f0 is measured with a frequency measuring device 17. A correction value F1 is outputted with a correction value converter 18. Further, in a corrector 20, a peak value EP1 is extracted from the quantized ultrasonic wave signal Ei by the command signal (b) of the device 13 and is subjected to product operation EP1XF1 with the output of the converter 18, and the result thereof is inputted to the device 13, whereby the internal defects of the material 9 are evaluated. |
