The Paton Welding Journal, 2005, №08

2005 №08 (09)

2005 №08 (11)

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The Paton Welding Journal, 2005, #8, 62-67 pages

Materials and technology for flux brazing and soldering of aluminium and aluminium to steel

O.M. Sabadash, V.F. Khorunov

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

Abstract
Peculiarities of brazing of aluminium using high-temperature fluxes of the K-Al-Si/F system, as well as soldering using low-temperature fluxes, containing a new class of activators, i.e. complex tetrafluoborates (TFB) of metals Pb(II), Zn(II) and Cd(II) with nitrogen-containing bases, such as benzatriazole and morpholine, characterised by high reactivity, have been studied. Chemical intecaktion of aluminium with salt melts of the of tire K-Al-Si/F ternary system results in formation of liquid alloy Al-Si at the interface. This alloy greatly improves spreading and filling of capillary gaps with brazing filler alloys, and it can independently perform the function of a brazing filler alloy. Reactive flux FAF540 is successfully applied for joining aluminium alloys containing up to 0.7 % Mg, as well as aluminium to stainless steel. In low-temperature soldering the metal coatings are deposited from a composition of complex TFB on the siirkice of aluminium parts boiioy soldered. The coatings can be readily wetted and dissolved bу Iow-melting solders and improve formation and properties of the aluminium joints.
Keywords: brazing, soldering, aluminium, steel-aluminium joints, non-corrosive fluxes, brazing filler alloys, solders, brazed joint, soldered joint, salt melts, potassium hexafluosilicate, low- temperature fluxes, activators, complex tetrafluoborates

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Suggested Citation

O.M. Sabadash, V.F. Khorunov (2005) Materials and technology for flux brazing and soldering of aluminium and aluminium to steel. The Paton Welding J., 08, 62-67.

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