Laser photoacoustic technique for ultrasonic surface acoustic wave velocity evaluation on porcelain

Abstract

A laser photoacoustic technique has been developed to evaluate the surface acoustic wave (SAW) velocity of porcelain. A Q-switched Nd:YAG laser at 1064 nm was focused by a cylindrical lens to initiate broadband SAW impulses, which were detected by an optical fiber interferometer with high spatial resolution. Multiple near-field surface acoustic waves were observed on the sample surface at various locations along the axis perpendicular to the laser line source as the detector moved away from the source in the same increments. The frequency spectrum and dispersion curves were obtained by operating on the recorded waveforms with cross-correlation and FFT. The SAW phase velocities of the porcelain of the same source are similar while they are different from those of different sources. The marked differences of Rayleigh phase velocities in our experiment suggest that this technique has the potential for porcelain identification.

Introducing theLaser PhysicsandLaser Physics Lettershighlights of 2016

“…• Laser photoacoustic technique for ultrasonic surface acoustic wave velocity evaluation on porcelain-a laser photoacoustic technique has been developed to evaluate the surface acoustic wave velocity of porcelain [66]. • Excimer laser ablation of aluminum: influence of spot size on ablation rate-the dependence of ablation rate of an Al alloy on laser beam spot size (10-150 µm) is investigated using an ArF excimer laser operating at a wavelength of 193 nm and pulse width less than 4 ns [67].…”