Open AccessLaser-induced Hertzian fractures in silica initiated by metal micro-particles on the exit surface
Author(s) -
Eyal Feigenbaum,
Rajesh N. Raman,
David A. Cross,
C. W. Carr,
Manyalibo J. Matthews
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.010527
Subject(s) - fluence , materials science , laser , optics , spheres , metal , fracture (geology) , composite material , momentum (technical analysis) , metallurgy , physics , astronomy , finance , economics
Laser-induced Hertzian fractures on the exit surface of silica glass are found to result from metal surface-bound micro particles. Two types of metal micro-spheres are studied (stainless-steel and Al) using ultraviolet laser light. The fracture initiation probability curve as a function of fluence is obtained, resulting in an initiation threshold fluence of 11.1 ± 4.7 J/cm 2 and 16.5 ± 4.5 J/cm 2 for the SS and Al particles, accordingly. The modified damage density curve is calculated based on the fracture probability. The calculated momentum coupling coefficient linking incident laser fluence to the resulting plasma pressure is found to be similar for both particles: 32.6 ± 15.4 KN/J and 28.1 ± 10.4 KN/J for the SS and Al cases accordingly.