Title :
Development of a scan system for Rayleigh, shear and longitudinal wave velocity mapping
Author :
Sathish, S. ; Martin, R.W.
Author_Institution :
Res. Inst., Dayton Univ., OH, USA
Abstract :
A high precision scanning acoustic microscope system to generate C-scan type velocity images of Rayleigh, surface skimming longitudinal (SSLW) and surface skimming shear waves (SSSW), has been developed. The acoustic microscope utilizes impulse excitation to separate in the time domain the direct reflected signal from the surface acoustic wave signals. Differences in the arrival times of these signals at two defocuses are used to compute the velocity and display a 2D x/y velocity in real time during the scan. A map of the Young´s modulus of the material is generated using the velocity images. Examples of measurement on standard samples and Ti-6Al-4V alloys are presented.
Keywords :
Rayleigh waves; Young´s modulus; acoustic microscopy; time-domain analysis; ultrasonic materials testing; C-scan type velocity images; Rayleigh wave; Young´s modulus; acoustic microscope; defocuses; direct reflected signal; impulse excitation; standard samples; surface acoustic wave signals; surface skimming longitudinal waves; surface skimming shear waves; time domain; velocity images; velocity mapping; Acoustic imaging; Acoustic materials; Acoustic measurements; Acoustic waves; Focusing; Lenses; Microscopy; Optical materials; Surface acoustic waves; Velocity measurement;
Conference_Titel :
Ultrasonics Symposium, 1999. Proceedings. 1999 IEEE
Conference_Location :
Caesars Tahoe, NV
Print_ISBN :
0-7803-5722-1
DOI :
10.1109/ULTSYM.1999.849470
