The Paton Welding Journal, 2003, №04

2003 №04 (01)

2003 №04 (03)

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The Paton Welding Journal, 2003, #4, 7-12 pages

Special features of capillary waves in the vapour-gas channel in electron beam welding of thick metal

V.M. Nesterenkov

E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.

Abstract
Features of natural oscillations of liquid metal on the vapour-gas channel walls have been studied. It is shown that in welding with a uniformly-moving electron beam capillary waves form on the melt surface under the impact of reaction force of recoil pressure, arising as a result of electron beam interaction with the channel front wall. These capillary forces have a discrete spectrum of natural frequencies, the density of which increases with the penetration depth. A variance relation has been derived for the capillary waves on the inner surface of a cylindrical channel. Such low-frequency oscillations of the melt may result in instability of the welding process.
Keywords: electron beam welding, vapour-gas channel, capillary waves, hydrodynamic stability, laminar flow, spectrum of natural oscillations, variance relation, damping coefficient

References

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Suggested Citation

V.M. Nesterenkov (2003) Special features of capillary waves in the vapour-gas channel in electron beam welding of thick metal. The Paton Welding J., 04, 7-12.

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