| 摘要 |
PURPOSE:To improve reliability of flaw-detecting inspection by a method wherein water subjected to a pressure-reducing and deaerating processing is used as a transmission medium for ultrasonic waves. CONSTITUTION:City water is put in a vessel made of stainless steel in which a pressure can be reduced and which has an inner capacity of 10l. The water is sucked for one hour by a rotary pump through a silica gel and the water thus obtained is transferred into a water tank 18 in which an ultrasonic flaw- detecting inspection device is installed. An Si3N4 ceramic ball of a surface roughness 10 mmphi at 0.05mum being used as a body to be inspected, this ball 10 is put on a roller 11 for driving. Subsequently, a polymer probe 15 of which the speed of rotation of the ball is 300 rpm. A frequency 50MHz, the diameter 5 mmphi and a focal distance 10 mm is fixed to a probe fitting arm 16 and then flaw-detecting inspection of the ball is conducted. By using water subjected to reduced deaerating processing as a transmission medium for ultrasonic waves in this way, reliability of the flaw-detection inspection can be improved. |
