| 摘要 |
PURPOSE:To prevent the futile consumption of a coupling material and to enhance the workability in the case the flaw in the object to be tested is searched by the sensor, by providing a magnet along the sliding face of said sensor, and using a magnetic liquid as the coupling material. CONSTITUTION:The ultrasonic wave of about 2-10MHz is generated by the ultrasonic flaw sensor 1. The reflected wave or attenuated ultrasonic wave caused by the flaws in the object to be tested is received, and the presence of the flaws is sensed. In this case, an annular magnet 5 is provided along the sliding face of said sensor 1, and the magnetic liquid is used as the coupling material. As the magnetic liquid, is used the liquid wherein the 3-8vol% magnetic material of Fe2O3, Fe3O4, or the like is included in linseed oil. When the sensor 1 is slidden along the object to be tested 2, the coupling material 4 is adsorbed to the magnet 5, and the phenomena such as the contamination and the like of the machine caused by the dropping of the coupling material 4 can be prevented. |
