Generation of Custom Acoustic Harmonic Bursts from Spherical Helmholtz Resonators Using Q-Switched Nd:YAG Laser Induced Plasma

Abstract We reported a new method for generating a 4 to 25 ms high power acoustic harmonic bursts, reaching more than 110 dB Sound Pressure Level (SPL), from the spherical Helmholtz resonators. The method uses Q-switched Nd:YAG laser pulses (wavelength = 1064 nm, pulse width = 6 ns, and energy = 450 mJ) to induce plasma shocks inside an AISI 316L stainless steel cavity. The confined plasma shock produces an acoustic burst of temporal standing waves which are characterized by a wide harmonic bandwidth. The frequency response of the system depends on the geometry of the used Helmholtz resonator as well as the laser wavelength (with constant laser pulse duration and fluence). The experiments reveal the dependence of the odd/even harmonic on laser wavelength. This method is a prospective alternative for the dodecahedron loudspeakers, other sources in ISO and standard audio tests.

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Single Pulse Laser Ablation of AISI 316L Stainless Steel Surface Using Nd:YAG Laser Irradiation

Acta Physica Polonica A ◽

10.12693/aphyspola.125.439 ◽

2014 ◽

Vol 125 (2) ◽

pp. 439-441 ◽

Cited By ~ 4

Author(s):

P. Demir ◽

E. Kacar ◽

E. Akman ◽

A. Demir

Keyword(s):

Stainless Steel ◽

Laser Ablation ◽

Nd:Yag Laser ◽

Steel Surface ◽

316L Stainless Steel ◽

Pulse Laser Ablation ◽

Single Pulse ◽

Stainless Steel Surface ◽

Aisi 316L ◽

Aisi 316L Stainless Steel

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Superficial changes on the Inconel 600 superalloy by picosecond Nd:YAG laser operating at 1064, 532, and 266 nm: Comparative study

Laser and Particle Beams ◽

10.1017/s0263034611000899 ◽

2012 ◽

Vol 30 (2) ◽

pp. 249-257 ◽

Cited By ~ 5

Author(s):

J. Stašić ◽

B. Gaković ◽

M. Trtica ◽

T. Desai ◽

L. Volpe

Keyword(s):

Comparative Study ◽

Nd:Yag Laser ◽

Surface Damage ◽

Laser Pulses ◽

Laser Wavelength ◽

Ultrashort Laser Pulses ◽

Periodic Surface ◽

Inconel 600 ◽

Hydrodynamic Effects ◽

Ultrashort Laser

AbstractA comparative study of superficial changes on the superalloy Inconel 600, induced by a picosecond Nd:YAG laser operating at 1064, 532, and 266 nm, is presented. All of the laser wavelengths, as well as the used fluences of 2.5 (1064 nm), 4.3 (532 nm), and 0.6 J/cm2 (266 nm) were found to be adequate for inducing surface variations. Quite different surface features were produced depending on the laser wavelength used. The measured surface damage thresholds were 0.25, 0.13 and 0.10 J/cm2 for 1064, 532, and 266 nm, respectively. Drastic differences, in function of the wavelength used, were recorded for the crater depths, as well the appearance of hydrodynamic effects and periodic surface structures. Differences in crater depths were explained via an easier propagation of the first harmonic laser radiation (1064 nm) through the ejected material and plasma compared to a radiation at 532 and 266 nm. Finally, changes in the surface oxygen content caused by ultrashort laser pulses were considered.

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