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Title: Nanosecond-laser plasma-assisted ultradeep microdrilling of optically opaque and transparent solids

Abstract

A mechanism of ultradeep (up to tens of microns per pulse, submillimeter total hole depths) plasma-assisted ablative drilling of optically opaque and transparent materials by high-power nanosecond lasers has been proposed and verified experimentally using optical transmission and contact photoacoustic techniques to measure average drilling rates per laser shot versus laser intensity at constant focusing conditions. The plots of average drilling rates versus laser intensity exhibit slopes which are in good agreement with those predicted by the proposed model and also with other experimental studies. The proposed ultradeep drilling mechanism consists of a number of stages, including ultradeep 'nonthermal' energy delivery into bulk solids by the short-wavelength radiation of the hot ablative plasma, bulk heating and melting, accompanied by subsurface boiling in the melt pool, and resulting melt expulsion from the target.

Authors:
; ; ;  [1]
  1. Department of Chemistry and Physics, Arkansas State University, State University, Arkansas 72467-0419 (United States)
Publication Date:
OSTI Identifier:
20982693
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 4; Other Information: DOI: 10.1063/1.2434829; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABLATION; DRILLING; LASER BEAM MACHINING; MELTING; PHOTOACOUSTIC EFFECT; PLASMA; SILICON

Citation Formats

Paul, Stanley, Kudryashov, Sergey I., Lyon, Kevin, and Allen, Susan D.. Nanosecond-laser plasma-assisted ultradeep microdrilling of optically opaque and transparent solids. United States: N. p., 2007. Web. doi:10.1063/1.2434829.
Paul, Stanley, Kudryashov, Sergey I., Lyon, Kevin, & Allen, Susan D.. Nanosecond-laser plasma-assisted ultradeep microdrilling of optically opaque and transparent solids. United States. doi:10.1063/1.2434829.
Paul, Stanley, Kudryashov, Sergey I., Lyon, Kevin, and Allen, Susan D.. Thu . "Nanosecond-laser plasma-assisted ultradeep microdrilling of optically opaque and transparent solids". United States. doi:10.1063/1.2434829.
@article{osti_20982693,
title = {Nanosecond-laser plasma-assisted ultradeep microdrilling of optically opaque and transparent solids},
author = {Paul, Stanley and Kudryashov, Sergey I. and Lyon, Kevin and Allen, Susan D.},
abstractNote = {A mechanism of ultradeep (up to tens of microns per pulse, submillimeter total hole depths) plasma-assisted ablative drilling of optically opaque and transparent materials by high-power nanosecond lasers has been proposed and verified experimentally using optical transmission and contact photoacoustic techniques to measure average drilling rates per laser shot versus laser intensity at constant focusing conditions. The plots of average drilling rates versus laser intensity exhibit slopes which are in good agreement with those predicted by the proposed model and also with other experimental studies. The proposed ultradeep drilling mechanism consists of a number of stages, including ultradeep 'nonthermal' energy delivery into bulk solids by the short-wavelength radiation of the hot ablative plasma, bulk heating and melting, accompanied by subsurface boiling in the melt pool, and resulting melt expulsion from the target.},
doi = {10.1063/1.2434829},
journal = {Journal of Applied Physics},
number = 4,
volume = 101,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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