Abstract: Apparatus and a process are disclosed for cleaning and/or fluxing circuit card assemblies. The assemblies are moved through an enclosure in which they are sprayed with cleaning and/or fluxing liquid from fenestrated cylinders rotating above and below the path of the assemblies and disposed laterally thereacross. The complex spray impact pattern created by the simultaneous movements of the assemblies and the cylinders effects thorough cleaning and/or fluxing of the assemblies. Separate control of liquid pressure from the cylinders prevents unsoldered components from being dislodged from the assemblies during cleaning and or fluxing.

Abstract: A process for assembling parts of a lightweight structure of aluminum having a multitude of joints. The process includes the following steps:(1) cleaning surfaces of all the parts;(2) selectively depositing on the surfaces a layer of nickel and then tin;(3) selectively plating on the tin layer where joints occur a lead/tin eutectic alloy solder;(4) add flux;(5) fixturing the parts together to form the structure;(6) heating the structure in a vapor phase apparatus;(7) removing the structure from the fixture; and(8) cleaning the structure.By using the above process an antenna faceplate having over 3000 joints was soldered.

Abstract: A technique for soldering is provided wherein the solder contains a nominal amount of 4 to 5% tin and the remainder lead. A solder flux is utilized which incorporates a lead compound, such as lead acetate. When the solder and flux is heated, a redox reaction will take place in which the lead ions in the flux will replace the alloyed tin in the solder, thereby reducing the tin content of the solder, whereby the ductility of the solder joint is improved.

Abstract: Disclosed is a method of forming solder terminals for a pinless module, preferably for a pinless metallized ceramic module. The method is comprised of the following steps: forming a substrate having a pattern of conductors formed onto its top surface and preformed via-holes extending from the top to bottom surface; applying a droplet of flux at at least one of said preformed via-hole openings of the bottom surface of said substrate to fill said via-holes with flux by capillarity and form a glob of flux at the bottom openings; applying a solder preform, i.e.

Abstract: A method for the production of a heat exchanger having a core part thereof formed by joining a tube of aluminum material and heat-transfer fins of aluminum material with a brazing material, which method is characterized by effecting said brazing by the use of a flux obtained by suspending a potassium fluoroaluminate complex in an aqueous solution of a pigment-forming water-soluble compound.

Abstract: The present invention is directed to a method for soldering each of a plurality of members (40), arranged in one or more parallel rows, to a separate one of a plurality of metallized pads (42) on a substrate (10), each pad being contiguous with a corresponding member. The method is initiated by tilting the substrate so that one end of each row of members and the metallized pads contiguous therewith are at a higher elevation than the other end. A stream (80) of molten solder and a dripping stream (88) of flux droplets are directed onto the substrate into the regions where the members are contiguous with the metallized pads. Simultaneously, the substrate is displaced relative to the streams along a path (96) inclined with respect to the horizontal and parallel to the rows of members so that the members and the metallized pads are successively coated with solder and then flux.

Abstract: An electronic component tinning apparatus comprising a longitudinal base unit having two longitudinally extending sides connected to a first end and an opposing second end, a top portion connected to and bounded by said sides and ends with an open longitudinal central cavity, and two spaced-apart, parallel longitudinally extending rails mounted on the top portion on opposing sides of said central cavity; a flux tank mounted in said central cavity approximate said first end to hold a liquid flux for flux-coating electronic component leads; a heated pot mounted in said central cavity approximate said second end to hold a hot molten solder bath for tinning the electronic component leads; a powered, wheeled electronic-component transport adapted to ride on said rails to carry electronic components from said first end over the flux tank to the second end over said solder pot and back again; two powered cam means mounted in said transport, rotatable to a high transport position and a low processing position, said c

Abstract: A method of applying a material of particulate form to the surface of an object by using a liquid, wherein the liquid is applied to the surface of the object to provide a film of the liquid thereon, and then the material of particulate form is applied to the film of the liquid on the surface of the object. Excess liquid may be removed from the surface of the object by using a jet of air current before the material of particulate form is applied to the film of the liquid on the surface of the object.

Abstract: A soldering method using a solder paste composed of solder alloy powder and soldering flux comprising rosin, thixotropic agent, activator, organic solvent and azobis compound such as 1,1'-azobis (cyclohexane-1-carbonitrile) as a free radical generator. The 1,1'-azobis (cyclohexane-1-carbonitrile) generates free radicals of cychlohexane-1-carbonitrile when heated in soldering, and the generated free radicals urge the activator to liberate hydrogen halide which enhances a removing effect of oxide film over a metal surface to be soldered. The azobis compound contributes to diminish the amount of activator and, consequently, hydrogen halide in the flux. The viscosity of the solder paste does not vary for a long time, which results in allowing the solder paste have a long shelf life. Since generation of the free radical is not decreased even though a soldering temperature decreased, which results in increasing solderability for low temperature soldering.

Abstract: A method and apparatus for preparing printed circuit boards having flattened solder bumps for the mounting of surface mount components is provided. Using well-known techniques, solder paste is screen-printed onto printed circuit boards and reflowed and cleaned to form discrete solder bumps. Using roller machines, the peaks of the solder bumps are flattened and adhesive solder flux is applied to the flattened tops of the solder bumps. The adhesive solder flux holds the surface mount components in position after placement and during vapor phase reflow.

Abstract: A long chain organic acid, such as stearic acid, is used as a flux to bond aluminum to electro-deposited sheet of aluminum, magnesium, or alloys thereof.

Abstract: An aluminum alloy including magnesium can be joined by brazing even when flux made of potassium fluoaluminates is employed. The aluminum alloy including magnesium is heated in a vacuum, so that magnesium in the aluminum alloy evaporates from the surface of the aluminum alloy. The weight ratio of magnesium at the surface of the aluminum alloy can be reduced to less than 0.5 as a result of the heating step. The aluminum alloy treated by this operation is, thereafter covered with brazing material and clad with flux. After that, the aluminum alloy is heated in a furnace in order to melt the brazing material.

Abstract: Solder flux is applied to the face of a printed circuit board (24) or the like by flowing a foam (30) of liquid flux bubbles upwardly through the top of a chimney flue (10) and into contact with the board face which is top passed over the top of the flue. The size of bubbles adjacent the face of the board is controlled by placing a grid screen (26) within and immediately beneath the top of the flue. The openings (26a) in the grid screen allow passage therethrough of smaller bubbles (34) but prevent passage of larger bubbles (32). The force of the board face on the foam urges the larger bubbles downwardly into contact with the grid screen where the grid wires of the screen pierce and thereby break the larger bubbles into smaller bubbles which then rise to the face of the board.

Abstract: A heat exchanger and a method of manufacturing a heat exchanger by brazing metal members mainly made of Al or Al alloy is disclosed. The heat exchanger has a plurality of brazed metal members, at least one of the brazed metal members being made of brazing sheet clad with a brazing material. The brazed portions of the metal members or the whole surface of the heat exchanger are coated with a corrosion-resistant fluoride flux consisting essentially of 25-40% KF, 38-54% AlF3 and 3-30% ZnF2 by weight which forms a corrosion-inhibiting metallic film.

Abstract: A method of brazing aluminum articles in a continuous furnace, to which a step for producing fluoride fluxes is incorporated. An aqueous suspension of KAlF.sub.4 is produced continuously and in situ in the system of the method by the reaction of starting materials, Al(OH).sub.3, HF, and KOH, and the suspension as it is produced or with the dilution by water is sprayed over the articles which move through the furnace.

Abstract: A solder flux comprises rosin, an activator, an optional surfactant and the dimer of linoleic acid.

Abstract: Disclosed is a process for joining two metal surfaces together with solder in which the surfaces to be soldered are first treated with an organic phosphorus-containing liquid flux which is relatively non-corrosive and which has a high degree of lubricity.

Abstract: A phosphoric acid flux with good fluxing efficiency and high viscosity, and one which is especially suitable for use in the soldering of copper and copper-plated stainless steel. The flux is in the form of a viscous fluid, or a thermally unstable emulsion when the fluid is combined with a pasty vehicle. The viscous fluid contains phosphoric acid and an organic material (molecular weight between 4,000 and 20,000) from the group consisting of polyethers and polyimines or mixtures thereof having an atomic ratio of carbon to ether oxygen plus imine nitrogen between 1.5 and 3.1.

Abstract: A phosphoric acid flux with good fluxing efficiency and high viscosity, and one which is especially suitable for use in the soldering of copper, stainless steel and copper-plated stainless steel. The flux is in the form of a viscous fluid, or a thermally unstable emulsion when the fluid is combined with a pasty vehicle. The viscous fluid contains phosphoric acid, copper containing material and an organic material (molecular weight between 4,000 and 20,000) from the group consisting of polyethers and polyimines or mixtures thereof having an atomic ratio of carbon to ether oxygen plus imine nitrogen between 1.5 and 3.1.

Abstract: The gas supplied to a foam fluxer utilized for wave soldering is presaturated with a flux thinner compatable with the flux solvent utilized in the foam fluxer to eliminate evaporation of solvent in the foam fluxer and maintain the temperature and specific gravity of the flux solution constant.

Abstract: Wax-flux compositions for use in low-temperature soldering processes comprise (A) a major amount of a wax and (B) an effective amount to cause fluxing, at or below the soldering temperature of the piece to be soldered, of a wax-soluble alkylaryl sulfonic acid. A process for soldering electrical components to a printed circuit board comprises (A) applying a molten wax-flux composition as described above to the metal pattern side of the board, (B) allowing the wax-flux composition to solidify, (C) trimming the component leads, and (D) soldering the components to the printed circuit board.

Abstract: Wax-flux compositions for use in low-temperature soldering processes comprise (A) a major amount of a wax and (B) an effective amount to cause fluxing, at or below the soldering temperature of the piece to be soldered, of a wax-soluble diester of sulfomalic acid. A process for soldering electrical components to a printed circuit board comprises (A) applying a molten wax-flux composition as described above to the metal pattern side of the board, (B) allowing the wax-flux composition to solidify, (C) trimming the components leads, and (D) soldering the components to the printed circuit board.

Abstract: Soldering of stainless steels utilizing soft solders and, in conjunction therewith, flux compositions containing a major proportion of orthophosphoric acid and a minor proportion of a mono- or di-ammonium phosphate, or an amine mono- or di-orthophosphate, advantageously in the presence of water, and desirably in admixture with various supplemental materials, said compositions containing at least 50% of free orthophosphoric acid.

Abstract: The soldering alloy comprises at least :65 to 85% lead in weight12 to 30% cadmium in weight1 to 6% antimony in weight0.5 to 1% tin in weight.In a method for soldering metal parts, the parts are submitted to an organic flux on the portions thereof to be connected together, said portions are coated with the above mentioned soldering alloy, then they are heated to the liquidus temperature of the soldering alloy while being held together in contact.

Abstract: The invention relates to a novel non-corrosive rosin oil flux and a novel method of soldering which comprises the use of said flux.

Abstract: In methods of joining metal surfaces involving heating to a temperature above about 560.degree.C, the use of a flux comprising a mixture of potassium fluoaluminates. Particularly for brazing aluminum, a flux consisting essentially of potassium fluoaluminate complexes (e.g. KAlF.sub.4 and K.sub.3 AlF.sub.6) may be employed, having a composition corresponding to an AlF.sub.3 /KF ratio, in parts by weight, between about 65:35 and about 45:55. The flux is essentially free of unreacted potassium fluoride and may be in divided solid form.