Effects of Beam Size and Pulse Duration on the Laser Drilling Process

A two-dimensional axisymmetric transient laser drilling model is used to analyze the effects of laser beam diameter and laser pulse duration on the laser drilling process. The model includes conduction and convection heat transfer, melting, solidification and vaporization, as well as material removal resulting from the vaporization and melt ejection. The validated model is applied to study the effects of laser beam size and pulse duration on the geometry of the drilled hole. It is found that the ablation effect decrease with the increasing beam diameter due to the effect of increased vaporization rate, and deeper hole is observed for the larger pulse width due to the higher thermal ablation efficiency.

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Effect of Laser Beam Diameter on Cut Edge of Steel Plates Obtained by Laser Machining

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.467.227 ◽

2013 ◽

Vol 467 ◽

pp. 227-232 ◽

Cited By ~ 4

Author(s):

Imed Miraoui ◽

Mouna Zaied ◽

Mohamed Boujelbene

Keyword(s):

Laser Beam ◽

Laser Cutting ◽

Steel Plates ◽

Beam Diameter ◽

Power Laser ◽

Laser Beam Diameter ◽

Machined Surface ◽

Cut Edge ◽

Thermal Influence ◽

Cut Surface

Laser cutting is a thermal process which is used contactless to separate materials. In the present study, high-power laser cutting of steel plates is considered and the thermal influence of laser cutting on the cut edges is examined. The microstructure and the microhardness of the cut edge are affected by the input laser cutting parameter: laser beam diameter. The aim of this work is to investigate the effect of the laser beam diameter on the microhardness beneath the cut surface of steel plates obtained by CO2 laser cutting. The cut surface was studied based on microhardness depth profiles beneath the machined surface. The results show that laser cutting has a thermal effect on the surface microstructure and on the microhardness beneath the cut section. Also the microhardness of the hardening zone depends on the laser beam diameter.

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Analysis of Roughness and Heat Affected Zone of Steel Plates Obtained by Laser Cutting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.974.169 ◽

2014 ◽

Vol 974 ◽

pp. 169-173 ◽

Cited By ~ 5

Author(s):

Imed Miraoui ◽

Mohamed Boujelbene ◽

Emin Bayraktar

Keyword(s):

Surface Roughness ◽

Laser Beam ◽

Heat Affected Zone ◽

Laser Power ◽

Laser Cutting ◽

Major Effect ◽

Steel Plates ◽

Beam Diameter ◽

Laser Beam Diameter ◽

Cut Surface

In the present study, high-power CO2 laser cutting of steel plates has been investigated and the effect of the input laser cutting parameters on the cut surface quality is analyzed. The average roughness of the cut surface of the specimens, produced by different laser beam diameter and laser power, were measured by using roughness tester. The scanning electron microscopy SEM is used to record possible metallurgical alterations on the cut edge. The aim of this work is to investigate the effect of laser beam diameter and laser power on the cut surface roughness and on the heat affected zone width HAZ of steel plates obtained by CO2 laser cutting. An overall optimization was applied to find out the optimal cutting setting that would improve the cut surface quality. It was found that laser beam diameter has a negligible effect on surface roughness but laser power had major effect on roughness. The cut surface roughness decreases as laser power increases. Improved surface roughness can be obtained at higher laser power. Also, laser beam diameter and laser power had major effect on HAZ width. It increases as laser power increases.

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A Parameters Optimization of the CO2 Laser Drilling Process for HDI Microvia Fabrication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.214.451 ◽

2012 ◽

Vol 214 ◽

pp. 451-454 ◽

Cited By ~ 1

Author(s):

You Zuo Hu ◽

Wei He ◽

Wei Dong Xue ◽

Zhi Hua Tao ◽

Yu Xing Huang ◽

...

Keyword(s):

Pulse Width ◽

Printed Circuit Boards ◽

Laser Energy ◽

Experimental Parameter ◽

Laser Drilling ◽

Parameters Optimization ◽

Laser Source ◽

Drilling Process ◽

Beam Diameter ◽

Via Holes

The blind via holes formation by laser drilling is one of the key technologies for demanding high density interconnect printed circuit boards. In this paper , the drilling conditions of drilling the blind via holes and the quality of the drilled holes are examined using a CO2 laser source against the FR4 board without copper foil.We chose laser energy,pulse shot,pulse width and diameter of beam as the experimental parameter . The results showed that laser energy and beam diameter played a more important role on changing the blind vias’ diameter than pulse shot and pulse width .While the pulse shot and pulse width take more important role in changing the depth of vias.

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Theoretical and Experimental Investigation of Laser Drilling in a Partially Transparent Medium

Journal of Electronic Packaging ◽

10.1115/1.2905444 ◽

1992 ◽

Vol 114 (1) ◽

pp. 71-80 ◽

Cited By ~ 9

Author(s):

T. Nowak ◽

R. J. Pryputniewicz

Keyword(s):

Laser Beam ◽

Three Dimensional ◽

Laser Drilling ◽

Drilling Process ◽

Transparent Medium ◽

Finite Sample ◽

Cross Sectional ◽

Quantitative Correlation ◽

Study Results ◽

Successful Prediction

An investigation of pulsed, laser drilling in a partially transparent medium was conducted. The study included both theoretical and experimental analyses. The theoretical analysis included development of a computer simulation to model the laser drilling process—a three-dimensional finite difference solution with temperature-dependent thermal properties, finite sample geometry, and experimentally determined laser beam characteristics. Both qualitative and quantitative correlation of the theoretical and experimental results was good with successful prediction of hole shapes and minimum error in the theoretically predicted cross-sectional areas of the laser-drilled holes ranging approximately ± three percent over the range of energies per laser pulse considered in this study. Results of calculations and experiments demonstrated the importance of the shape and irradiance distribution of the incident laser beam on the quality of laser-drilled holes in Al2O3 samples.

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J. C. Laser beam diameter for port wine stain treatment

Plastic & Reconstructive Surgery ◽

10.1097/00006534-199209000-00065 ◽

1992 ◽

Vol 90 (3) ◽

pp. 545

Author(s):

David B. Apfelberg ◽

r Keijze ◽

J. W Pickering ◽

Gemert van

Keyword(s):

Laser Beam ◽

Beam Diameter ◽

Port Wine Stain ◽

Port Wine ◽

Laser Beam Diameter

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Effects of laser beam diameter on electromagnetically induced transparency due to Zeeman coherences in Rb vapor

Physica Scripta ◽

10.1088/0031-8949/2013/t157/014019 ◽

2013 ◽

Vol T157 ◽

pp. 014019

Author(s):

S N Nikolić ◽

A J Krmpot ◽

N M Lučić ◽

B V Zlatković ◽

M Radonjić ◽

...

Keyword(s):

Laser Beam ◽

Electromagnetically Induced Transparency ◽

Beam Diameter ◽

Laser Beam Diameter ◽

Rb Vapor ◽

Induced Transparency

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An integrated analysis of productivity, hole quality and cost estimation of single-pulse laser drilling process

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420968161 ◽

2020 ◽

pp. 095440542096816

Author(s):

Shoaib Sarfraz ◽

Essam Shehab ◽

Konstantinos Salonitis ◽

Wojciech Suder ◽

Misbah Niamat ◽

...

Keyword(s):

Pulse Duration ◽

Flow Rate ◽

Pulse Energy ◽

Gas Flow ◽

Single Pulse ◽

Laser Drilling ◽

Drilling Process ◽

Gas Flow Rate ◽

Hole Quality ◽

Drilling Cost

Laser drilling is a well-established manufacturing process utilised to produce holes in various aeroengine components. This research presents an experimental investigation on the effects of laser drilling process parameters on productivity (material removal rate), hole quality (hole taper) and drilling cost. Single-pulse drilling was employed to drill a thin-walled Inconel 718 superalloy plate of 1 mm thickness using pulsed Nd:YAG laser. The experiments were designed using Box-Behnken statistical approach to investigate the impacts of pulse energy, pulse duration, gas pressure and gas flow rate on the selected responses. Multi-objective optimisation was performed using response surface methodology (RSM) based grey rational analysis (GRA) to identify optimal drilling conditions aiming to maximise the MRR and minimise hole taper and drilling cost. The optimal combination of drilling parameters was found as pulse energy of 20 J, pulse duration of 6 ms, gas pressure of 100 psi and gas flow rate of 40 mm3/s. A detailed cost analysis identified labour cost, gas consumption and machine costs as the major cost elements of the laser drilling process.

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