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Quantification of Melt Ejection Phenomena During Laser Drilling

Published online by Cambridge University Press:  10 February 2011

K.T. Voisey ,
C.F. Cheng  and
T.W. Clyne
K.T. Voisey
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, England, Tel: +44 (0)1223 334332, Fax: +44 (0)1223 334567
C.F. Cheng
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, England, Tel: +44 (0)1223 334332, Fax: +44 (0)1223 334567
T.W. Clyne
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, England, Tel: +44 (0)1223 334332, Fax: +44 (0)1223 334567, Email: [email protected]
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Abstract

During laser drilling, material removal in general occurs both by vaporisation and by the expulsion of molten material. The latter commonly arises as a result of the rapid build-up of gas pressure within the growing cavity as evaporation takes place, but the precise mechanisms responsible for the phenomenon are still unclear. The current work is aimed at gaining an insight into these mechanisms via measurements of the amount of material ejected from cavities during laser drilling under different conditions. Attention is first devoted to the issues which need to be considered when making experimental measurements of the fraction of material removed by melt ejection. These include the collection efficiency and the possibility of chemical changes occurring during the process. Results are then presented from work with a range of metallic substrates (mild steel, tungsten, copper, titanium, aluminium and nickel), drilled with a JK701 Nd-YAG laser under different conditions. Observed variations in the melt ejection levels have been studied for mild steel and aluminium and these are briefly considered in terms of the expected effects of certain material property values and the mechanisms of melt ejection. Results from an existing finite difference heat flow model are used to investigate the significance of melt ejection.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 617: Symposium J – Laser-Solid Interactionsfor Materials Processing , 2000 , J5.6
Copyright
Copyright © Materials Research Society 2000

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References

1 Bostanjoglo, G. et al. Processing of Ni-based Aero Engine Components with Repetitively Q-switched Ad: YAG Lasers. in High Power Lasers: Applications and Emerging Applications. 1996: Soc. Photo-Optical Instrumentation Engineers (SPIE).Google Scholar
2 Brandes, E. and Brook, G., eds. Smithells' Metals Reference Book. 7th Ed. ed. 1992, Butterworth Heinemann: Oxford.Google Scholar
3 Korner, C. et al. , Physical and Material Aspects in using Visible Laser Pulses of Nanosecond Duration for Ablation. Appl. Phys. A, 1996. 63: p. 123–131.Google Scholar
4 Murthy, J. et al. Investigation of the Drilling Dynamics in Ti-6A1-4V using High Speed Photography. in Laser Materials Processing Conference ICALEO '94. 1994. San Diego: Laser Institute of America.Google Scholar
5 Ramanathan, S. and Modest, M., High-Speed Photographic Studies of Laser Drilling of Ceramics and Ceramic Composites. J. of Laser Appls., 1995.7: p. 75–82.Google Scholar
6 Yilbas, B.S., study of Liquid and Vapor Ejection Processes During Laser Drilling of Metals. J. of Laser Applications, 1995. 7: p. 147–152.Google Scholar
7 Yilbas, B.S., Sahin, A.Z., and Davies, R., Laser Heating Mechanism Including Evaporation Process Initiating Laser Drilling. Int. J. of Machine Tools & Manufacture, 1995. 35(7): p. 1047–1062.Google Scholar
8 Yilbas, B.S. and Sami, M., Liquid Ejection and Possible Nucleate Boiling Mechanisms in Relation to the Laser Drilling Process. J. Phys. D: Appl. Phys, 1997. 30: p. 1996–2005.Google Scholar
9 Luft, A. et al. , A Study of Thermal and Mechanical Effects on Materials Induced by Pulsed Laser Drilling. Appl. Phys A, 1996. 63: p. 93–101.Google Scholar
10 Von Allmen, M., Laser Drilling Velocity in Metals. J. Appl. Phys., 1976. 47: p. 5460–5463.Google Scholar
11 Chan, C. and Mazurnder, J., One-Dimensional Steady State Model for Damage by Vaporization and Liquid Expulsion Due to Laser-material Interaction. J. Appl. Phys., 1987. 62(11): p. 4579–86.Google Scholar
12 Ganesh, R.K. et al. , A Model for Laser Hole Drilling in Metals. J. Computat. Physics, 1996. 125: p. 161–176.Google Scholar
13 Ganesh, R.K., Faghri, A., and Hahn, Y., A Generalized Thermal Modelingfor Laser Drilling Process. 1. Mathematical Modeling and Numerical Methodology. Int. J. Heat Mass Transfer, 1997. 40: p. 3351–3360.Google Scholar
14 Ganesh, R.K., Faghri, A., and Hahn, Y., A Generalized Thermal Modelingfor Laser Drilling Process 2. Numerical Simulation and Results. Int. J. Heat Mass Transfer, 1997. 40: p. 3361–3373.Google Scholar
15 Cheng, C.F., Tsui, Y.C., and Clyne, T.W., Application of a 3-D Heat Flow Model to Treat Laser Drilling of Carbon Fibre Compositesq. Acta Metall. et Mater., 1998. 46: p. 4273–4285.Google Scholar
16 Solana, P. et al. , Time Dependent Ablation and Liquid Ejection Processes during the Laser Drilling of Metals. J. Phys. D : Appl. Phys., 2000: p. in press.Google Scholar
17 Young, R.A., The Rietveld Method. Monographs on Crystallography. 1993, Oxford: Oxford University Press.Google Scholar