METHOD OF SOLDERING SILUMIN COATED ALUMINIUM AND ALUMINIUM ALLOYS Russian patent published in 2009 - IPC B23K1/20 B23K103/10 C23C22/34 

FIELD: welding jobs.

SUBSTANCE: invention can be used in soldering silumin coated aluminium and aluminium alloys at high temperatures. The proposed method comprises the steps that follow. First the surface to be soldered is degreased and/or degreased and etched. Then the said surface is subjected to treatment by water solution of fluorohydrogen acid mixed with alkaline metal fluorides, the concentration of components in the solution making, in percent by weight, the following values, i.e. fluorohydrogen acid - 1.0 to 35.0, alkaline metal fluoride - 0.2 to 22.0, water - the balance. Now the surface is dried and soldered in inert gas atmosphere with no fluxes, irrespective of curing time after treatment.

EFFECT: layer of aluminates produced on soldered surface boats practically equal thickness and provides for high quality of soldering.

4 cl, 1 tbl, 8 ex