DEVICE FOR MEASURING POROSITY RATE

PROBLEM TO BE SOLVED: To provide a method for inspecting a compound structure by a single ultrasonic converter in a nondestructive manner. SOLUTION: The nondestructive inspection method includes a process for determining the calibration amplitude of the transmission of ultrasonic waves that are generated from the single ultrasonic converter to a reflector in a soaking tank 312, to which fluid is filled and received again by the single ultrasonic converter. The method also includes a process for inserting the compound structure 306 into the soaking tank, to which fluid is filled between the reflector and the single ultrasonic converter. Furthermore, the method also includes a process for scanning the compound structure by the single ultrasonic converter and measuring the amplitude of measured ultrasonic waves in sound waves, reaching the single ultrasonic converter after moving in the compound structure, being reflected from a reflecting plate 302, and traveling in the structure. The measured amplitudes of the ultrasonic waves are corrected by the calibration amplitude and other measured transmission losses. One or both of the porosity rate in the compound structure and a digital image for indicating the measurement of the porosity rate are generated by the corrected amplitude of ultrasonic waves. COPYRIGHT: (C)2007,JPO&INPIT