| 摘要 |
PURPOSE:To provide a high sensitive ultrasonic flaw detecting method that is effective to the detection of those of structural materials such as concrete, refractories or the like, thickness of a structure and an internal flaw. CONSTITUTION:A short pulse transmitting wave is charged in a subject material 2 via a wide-band ultrasonic probe 7 and, after ultrasonic waves 3 propagated in the subject material are amplified by a receiving amplifier 11, a most significant frequency component is selected by a frequency stectrum analyzer 14. Next, a burst transmitting wave of the selected frequency is charged in the subject material, and the ultrasonic waves are received and amplified again and, after filtering it, it is taken in a signal processing computing element 17 simultaneously with a transmitting reference wave to be generated synchronously with the transmitting wave, and thus a mutual correlation arithmetic process is carried out. |
