A New Approach of Surface Roughness Measurement using Air-coupled Ultrasound
Y Lin Graduate student in Wood Science and Technology F C Beall Professor and Director University of California Forest Products Laboratory G C Johnson Professor Department of Mechanical Engineering University of California at Berkeley
ABSTRACT
This paper presents a new approach in surface roughness measurement through the use of air-coupled ultrasound. It has an obvious advantage over traditional liquid-coupled systems in that no contact is required with the surface. In the study, a pair of unfocused ultrasonic transducers was used in a pitch-catch mode to monitor the reflected ultrasonic signal from the surface. Experimental results demonstrated a strong correlation between the received signal parameters and the root mean square surface roughness. A range of roughness from ~20 to ~200 mm was detected, with a resolution of ~20-30 mm or better.
Publication Source: Proceedings of the 12th International Symposium on Nondestructive Testing of Wood University of Western Hungary, Sopron, 13-15 September 2000, ISBN 963 7180 88 5 Publisher: University of Western Hungary, H 9400 Sopron, P.O.Box 132, FAX: +36 99 311 103
