Development of Sound Pressure Field Evaluation system for NDE Ultrasonic Transducer Using Photoelastic CT Method

Research Project

Project/Area Number	06555208
Research Category	Grant-in-Aid for Developmental Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	Material processing/treatments
Research Institution	TOHOKU UNIVERSITY
Principal Investigator	DATE Kazuhiro Tohoku University, Faculty of Engineering, Professor, 工学部, 教授 (10111254)
Co-Investigator(Kenkyū-buntansha)	TABATA Yukihiro Japan Krautkramer Co. Ltd. Development Section Manager, 開発課課長 MIHARA Tsuyoshi Tohoku University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (20174112)
Project Period (FY)	1994 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥12,500,000 (Direct Cost: ¥12,500,000) Fiscal Year 1995: ¥4,500,000 (Direct Cost: ¥4,500,000) Fiscal Year 1994: ¥8,000,000 (Direct Cost: ¥8,000,000)
Keywords	CT Method / Photo Elasticity / 3 Dimensional Sound Field / NDE / Ultrasonic Inspection / Ultrasonic Transducer / Normal Probe
Research Abstract	Since ultrasonic inspection depend strongly on ultrasonic transducer, detail of the sound pressure field of each ultrasonic transducer used must be investigated. Most suitable measurement system was ultrasonic visualization system using photo elasticity. However, these method can only measure two dimensional sound pressure field which is not enough for standard transducer evaluation system. In this research, photoelastic computer tomography (CT) method was developed for three dimensional measurement of sound pressure distribution of a longitudinal wave. In a near field of the sound pressure distribution produced by the normal prove, an interference pattern which shows the three dimensional sound pressure distribution was observed. The effects of frequency and propergation distance on the three dimensional sound pressure distribution were observed and compared with wave theory. Near field of the sound pressure distribution of line focus beam transducer were also observed using this system.