抄録
The thermal spraying technique is widely used for various mechanical parts as a surface reforming technique. The operating environment is becoming increasingly harsh for superior mechanical performance, so the use environment of the sprayed coating has become severe. Therefore, the demand for technology that is checked non-destructively has become more insistent. For the purpose of this investigation, we reduced the thickness of the thermal sprayed coating by abrasion with blasting and used a bottom reflection echo in ultrasonic inspection for effective measurement of the quantity of abrasion of the thermal sprayed coating. The results obtained are summarized as follows. When the thickness of the thermal sprayed coating becomes thinner, the echo height increases. The reason is that the ultrasonic energy is absorbed by the thermal sprayed coating. The ultrasonic energy by which Al2O3 is absorbed compared to that of Fe-13Cr is small. The echo height when the thermal sprayed coating is in water is lower than when the thermal sprayed coating is in air. As mentioned above, the quantity of the thermal sprayed coating thickness could be estimated by ultrasonic inspection.
