SOFT BRAZING METHOD OF NOT PRODUCING ANY RESIDUE BY FLUX

摘要

PURPOSE:To obviate the leaving of residues owing to the reaction of flux, etc. on the base metal surfaces after soft brazing by placing a soft braze on the faying portions of the base metals, and heating the same in the vapor of an easy-to-evaporate solvent to let the soft braze melt and flow in. CONSTITUTION:Soft braze of Sn-Pb, Sn-Ag or the like is placed on the faying portions of the assembled parts consisting of base metals of pure copper, brass, tin plates, etc. The assembled parts to be soft brazed are inserted into the vapor of the solvent which is generated when a solvent such as dipropanol or ethanol is heated to temperatures higher by several - about 10 deg.C than its boiling temperature. This method makes it possible to obtain the soft-brazed zone of a good spread area. In addition, the parts are bonded in an oxidation-free atmosphere and therefore the corrosive product and residues owing to the reaction of flux, etc. are not produced and this eliminates the need for post-treatment and makes the appearance after the brazing clean.