Line source representation for laser-generated ultrasound in aluminum
Modeling the ultrasound generated by a laser source is critical for using noncontact laser-generated ultrasonic systems for the characterization of material properties. In this work, a laser line source was modeled and verified experimentally by measuring the ultrasonic shear wave signal generated in aluminum with a broadband laser generation/electromagnetic acoustic transducer (EMAT)-detection system. Results of calculations and experiments show that the amplitude directivity of a laser line source is identical to that of a point source in the plane perpendicular to the line axis while the temporal dependence differs.
Bernstein
JR
Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Spicer
JB