| 摘要 |
PURPOSE:To measure the degree of brittleness of a zirconium alloy material with high accuracy in a short period of time, by detecting the velocity of a false AE wave transmitting through a pressure tube made of a zirconium alloy. CONSTITUTION:A sensor 14 for transmission equipped with a pressure tube 12 made of a zirconium alloy receives a pulse signal of 10-100Hz from a pulse generator 16 and make the pressure tube 12 generates a false AE wave. The false AE wave is received by sensors 18, 20 for reception being attached separated by a prescribed distance, and is inputted via preamplifiers 22, 24 through main amplifiers 26, 28 to a time difference measuring device 30 respectively. Using the time difference measuring device 30, an arrival time difference DELTAt of the AE wave to the receiving sensors 18, 20 is measured, and thereby the velocity of propagation of the false AE wave in pressure tube 12 is obtained. A ratio V/V0 between the velocity of propagation V0 of the dummy AE wave in the initial state of the pressure tube 12 and that of the false AE wave after operation is obtained and the amount of orientation of a hydride is obtained, allowing the degree of the weakening of the pressure tube 12 to be evaluated. |
