Hostname: page-component-7dd5485656-6kn8j Total loading time: 0 Render date: 2025-10-31T22:03:45.669Z Has data issue: false hasContentIssue false
  • English
  • Français

Some aspects of the fluid dynamics of laser welding

Published online by Cambridge University Press:  20 April 2006

John Dowden ,
Michael Davis  and
Phiroze Kapadia
John Dowden
Affiliation:
Department of Mathematics, University of Essex, Colchester, U.K.
Michael Davis
Affiliation:
Department of Physics, University of Essex, Colchester, U.K.
Phiroze Kapadia
Affiliation:
Department of Physics, University of Essex, Colchester, U.K.
Get access Rights & Permissions [Opens in a new window]

Abstract

When a laser beam is used as the energy source for welding two pieces of metal together, a hole is formed perpendicular to the plane of the workpiece. The latter is moved relative to the laser and metal is transferred from the front to the rear by fluid flow round the hole. The equations governing the process are set out and the conditions at the two boundaries in the problem (one between the hole and the molten metal, and the other between the liquid and the solid states of the metal) are considered.

Approximate solutions of the problem for low welding speeds are obtained for four different models. The first is one in which the viscosity is taken to be constant. In the second, the viscosity is allowed to depend linearly on temperature. The third model divides the liquid into a region in which the cooler part is taken to be viscous and the hotter part inviscid; the fourth model is then constructed as a limit, with the liquid motion considered as wholly inviscid. It is found that the motion is not irrotational in this last model. The models all display a downstream displacement of the boundary between the solid and liquid states, in agreement with observations. An expression for the minimum power of the laser is calculated.

Information

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 126 , January 1983 , pp. 123 - 146
Copyright
© 1983 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Abramowitz, M. & Stegun, I. A. 1965 Handbook of Mathematical Functions. Dover.
Andrews, J. G. & Atthey, D. R. 1975 On the motion of an intensely heated evaporating boundary J. Inst. Maths. Applics 15, 59–72.Google Scholar
Andrews, J. G. & Atthey, D. R. 1976 Hydrodynamic limit to penetration of a material by a high-power beam. J. Phys. D: Appl. Phys. 9, 2181–2194.Google Scholar
Andrews, J. G., Atthey, D. R. & BYATT-SMITH, J. G. 1980 Weld-pool sag J. Fluid Mech. 100, 785–800.Google Scholar
Austin, J. B. 1932 Heat capacity of iron Indust. Engng Chem. 24, 1225–1235.Google Scholar
Batchelor, G. K. 1967 An Introduction to Fluid Dynamics. Cambridge University Press.
Carslaw, H. C. & Jaegar, J. C. 1959 Conduction of heat in solids. Clarendon.
Duley, W. W. 1976 CO2 Lasers: Effects and Applications. Academic.
Klemens, P. G. 1976 Heat balance and flow conditions for electron beam and laser welding J. Appl. Phys. 47, 2165–2174.Google Scholar
Lamb, H. 1932 Hydrodynamics, 6th edn. Cambridge University Press.
La Rocca, A. V. 1982 Laser applications in manufacturing. Sci. Am. 246(3), 80–87.Google Scholar
Malmuth, N. D. 1976 Temperature field of a moving point-source with change of state Int. J. Heat Mass Transfer 19, 349–354.Google Scholar
Mazumder, J. & Steen, W. M. 1980 Heat transfer for cw laser material processing J. Appl. Phys. 51, 941–947.Google Scholar
Ol'Shanskii, N. A. 1974 Movement of molten metal during electron-beam welding Svar. Proiz. 9, 12–14.Google Scholar
Pirri, A. N., Root, R. G. & Wu, P. K. S. 1978 Plasma energy transfer to metal surfaces irradiated by pulsed lasers A.I.A.A. J. 16, 1296–1304.Google Scholar
SWIFT-HOOK, D. T. & Gick, A. E. F. 1973 Penetration welding with lasers Welding J. 52, 492s–499s.Google Scholar
Tayler, A. B. 1975 The mathematical formulation of Stefan problems. In Moving boundary problems in heat flow and diffusion (ed. J. R. Ockendon & W. R. Hodgkin), pp. 120–137. Clarendon.