Development and testing of a prototype for remote determination of grain size in thin sheets by gap scanning with optically generated ultrasoundFunded under: ECSC-STEELRES 8C
It is shown that grain size in thin sheet steel can be determined by use of a laser ultrasound gap scanning technique based on ultrasound scattering Rayleigh, which contributes characteristically to ultrasound attenuation. The attenuation coefficient due to scattering is S f d, where S is the scatter parameter, f the ultrasound frequency, and d the grain size. A Q-switched Nd:YAG laser was used to generate the ultrasound waves. Interferometers were used to detect the ultrasound. The experiments show that for use on thin sheet steel, interferometers have to be sensitive to surface deflection at frequencies below approximately 250 kHz.
Bibliographic Reference: EUR 15468 DE (1995) 33 pp., FS, ECU 7
ISBN: ISBN 92-827-4681-X
Record Number: 199511275 / Last updated on: 1995-11-23
Original language: de
Available languages: de