Title :
Defect detection by surface acoustic waves generated by a multiple beam laser
Author :
Chenu, Catherine ; Royer, Daniel ; Fink, Mathias
Author_Institution :
Lab. Ondes et Acoust., Paris VII Univ., France
Abstract :
Laser-induced Surface Acoustic Wave (SAW) pulses of large amplitude have been launched on the surface of metallic samples. The non contact generation process involves a rectilinear set of photothermal sources equivalent to a phased array of ultrasonic transducers. Line and point source arrays created by a 16-beam YAG laser have been implemented. Two sets of experiments are presented: i) non destructive testing of thin surface breaking slots with giant SAW pulses launched by the line source array, ii) sectorial beam scanning of the surface by SAW generated by the point source array
Keywords :
Rayleigh waves; acoustic pulses; flaw detection; photoacoustic effect; photothermal effects; surface acoustic waves; ultrasonic materials testing; ultrasonic transducer arrays; 16-beam Q-switched Nd:YAG laser; Rayleigh wave pulses; defect detection; giant SAW pulses; laser-induced SAW pulses; line source arrays; metallic surface; multiple beam laser; noncontact generation process; nondestructive testing; photothermal sources; point source arrays; rectilinear set; sectorial beam scanning; surface acoustic wave generation; thin surface breaking slots; ultrasonic transducer phased array; Acoustic pulses; Acoustic signal detection; Acoustic waves; Optical arrays; Optical pulses; Phased arrays; Surface acoustic waves; Surface emitting lasers; Ultrasonic transducer arrays; Ultrasonic transducers;
Conference_Titel :
Ultrasonics Symposium, 1995. Proceedings., 1995 IEEE
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-2940-6
DOI :
10.1109/ULTSYM.1995.495692
