| 2005 №02 (02) | 2005 №02 (04) |
The Paton Welding Journal, 2005, #2, 14-17 pages
Pore formation in weld metal in submerged arc welding with surface saturation of grains with fluorine
V.G. Kuzmenko1, V.I. Guzej2
1E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.2City State Administration, Kiev, Ukraine
Abstract
Properties were studied of fused welding fluxes of manganese-silicate type, not containing fluorine and subjected to fluorinating heat treatment together with ammonia salt of hydrofluoric acid (NH4F) and magnesium hexafluosilicate (MgSiF6). It is established that the weld metal resistance to pore formation is achieved, when using 0.5 % each of the above salts for flux treatment. Fluorine content in the flux is equivalent to adding 0.4 % CaF2 to it. The effect is achieved due to local arrangement of fluorine on the flux grain surface.
Keywords: arc welding, fluxes, gas shielding, porosity, fluorinating heat treatment, nitrogen dissolution
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