| 摘要 |
PURPOSE:To make it possible to perform secure checking without destruction by tightly covering the entire surface of an unburned ceramic molded body which is a body to be checked with a solution-impermeable film, immersing the body in a solution, and scanning the body with an ultrasonic wave. CONSTITUTION:An organic fiber is added into silicon nitride original powder, and the kneaded body undergoes injection molding. Thus, e.g. ceramic turbocharger rotor 1 is obtained. Latex emulsion liquid is applied on the degreased rotor 1 and dried. Thus a film 4 is formed. The ceramic molded body 1 is immersed into water. Then, an ultrasonic wave having a frequency of 5MHz is oscillated with an ultrasonic wave oscillator 18, and scanning is performed. In this way, a crack 3 in a blade part 2 of the molded body 1 is detected. Therefore, a defective product can be removed at an early stage of a manufacturing steps, and the defective part can be identified. Thus the cost reduction can be realized by repair and the like. |
