Abstract: This invention relates to an improved process for application of a metal-comprising coating to a metal-comprising surface without using a flux. The metal-comprising surface must be wettable by or become wettable upon contact with a bath of the metal-comprising coating. Application of the coating is carried out in an environment which is inert at least with respect to the coating material during the time period of its application to the metal-comprising surface, and preferably inert with respect to both the coating material and the metal-comprising surface. The inert environment temperature is sufficiently low that no damage is done to the metal-comprising surface and no damage is done to other materials adjacent to the metal-comprising surface.

Abstract: A cam follower and process of manufacture in which a hardenable cast iron reaction member is welded, as by high energy beam welding, to the end of a tubular, mild steel base member. The surface of the reaction member may be decarburized before welding. The weld is preferably characterized by austenitic properties and is formed by an alloy of nickel with the metal of the cam follower members.

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: The present invention relates to a process for forming improved bonds between components of electrical or electronic devices. The process of the present invention preferably comprises annealing a metallic substrate to form a substantially uniform, substantially continuous oxide layer on a surface of the substrate, exposing the oxidized substrate to a reducing atmosphere so as to form an irregular surface on the substrate, and bonding another component to the irregular surface.

Abstract: The instant invention describes a method of repairing heat-resistant alloy parts which have been cracked or otherwise damaged due to exposure of combustion gases from a turbojet engine. The method includes chemically cleaning the surface of the part to remove the layer of contaminants and subjecting the part to a thermochemical treatment to thoroughly clean the cracks and other narrow, damaged areas. A diffusion brazing process is then utilized to fill the cracks or damaged areas.

Abstract: This invention is a process for joining metals to ceramics to form very strong bonds using low brazing temperature, i.e., less than 750.degree. C., and particularly for joining nodular cast iron to partially stabilized zirconia. The process provides that the ceramic be coated with an active metal, such as titanium, that can form an intermetallic with a low melting point brazing alloy such as 60Ag-30Cu-10Sn. The nodular cast iron is coated with a noncarbon containing metal, such as copper, to prevent carbon in the nodular cast iron from dissolving in the brazing alloy. These coated surfaces can be brazed together with the brazing alloy between at less than 750.degree. C. to form a very strong joint. An even stronger bond can be formed if a transition piece is used between the metal and ceramic. It is preferred for the transition piece to have a coefficient of thermal compatible with the coefficient of thermal expansion of the ceramic, such as titanium.

Abstract: The outer surface of a stainless steel utensil and one surface of an aluminum disk are cleaned and then separately heated at different temperatures. Thereafter, the disk is superimposed over the utensil and metallurgically bonded directly thereto by the application of pressure. Accumulated stress is relieved by cooling the bonded metal members to a temperature below 250.degree. F., followed by reheating to 700.degree.-950.degree. F.

Abstract: A method of welding, soldering or fusing a cast iron member to another member of cast iron or other metal, wherein the cast iron member is dipped in a hot concentrated aqueous solution of chromic acid, and washed with water before it is joined to the other member.

Abstract: The outer surface of a stainless steel utensil and one surface of an aluminum disk are cleaned and then separately heated at different temperatures. Thereafter, the disk is superimposed over the utensil and metallurgically bonded directly thereto by the application of pressure.

Abstract: A method for cleaning metal parts, particularly crack damaged gamma prime hardened nickel alloy parts, but also including stainless steels superalloys, and solid solution superalloys in order to render them brazable or otherwise bondable. The method makes use of a C-O-H-F atmosphere as the primary cleaning material wherein the atmosphere has an H/O ratio of 10.sup.4 or greater, and a C/F ratio of approximately 0.01 to less than 2.0. The preferred source of the C-O-H-F atmosphere is thermal decomposition of a fluorocarbon resin and a low moisture containing hydrogen gas although sources other than fluorocarbon resins are also disclosed.

Abstract: A method for preserving the solderability of copper conductors comprises stabilizing a cleaned, mildly etched conductor surface with a phosphoric acid-glycol solution then immersing the surface in imidazole followed by a rinse to remove excess imidazole.

Abstract: A method for relatively low temperature cleaning of metal parts, particularly stainless steels, superalloys, solid solution superalloys and gamma prime hardened nickel alloy parts, in order to render them brazable or otherwise bondable. The method makes use of a C--O--H--F atmosphere as the primary cleaning material. The preferred source of the C--O--H--F atmosphere is by thermal decomposition of a fluorocarbon resin and addition of a low moisture containing hydrogen gas.

Abstract: The method for cleaning metal parts, particularly crack damaged gamma prime hardened nickel alloy parts but also including stainless steels, superalloys, and solid solution superalloys in order to render them brazable or otherwise bondable. The method makes use of elemental fluorine as the primary cleaning material. A reducing gas such as hydrogen may be present. The preferred source of elemental fluorine is by thermal decomposition of a fluorocarbon resin. The cleaned part has a surface layer free of oxides and depleted of aluminum and titanium. It is brazable.

Abstract: The method for cleaning damaged metal parts, particularly crack damaged gamma prime hardened nickel alloy parts, in order to render them repairable by brazing. The method makes use of elemental fluorine as the primary cleaning material. A reducing gas such as hydrogen may be present. The preferred source of elemental fluorine is by thermal decomposition of a fluorocarbon resin. The cleaned part has a surface layer free of oxides and depleted of aluminum and titanium. It is brazable.

Abstract: A method for providing at room temperature a hermetic bonded seal between the surfaces of glass, ceramics, metals or any combination of these. The method comprises the steps of polishing the surfaces to be bonded and then plasma cleaning the surfaces. Next, a chemically cleaned bonding material such as indium is applied to the surfaces and a force is applied to the surfaces to be sealed at room temperature for a limited period of time to affect the bonded seal.

Abstract: A process for soldering aluminum fins to cooling pipes made of aluminum, copper, brass or steel to produce a cooling assembly. The fins are etched in the solution of sodium hydroxide, zinc chloride, technical urea and water and the cooling pipes are coated with a fusible alloy which is covered with a protective coating for attenuating electro-corrosion between the alloy and the aluminum fins. The aluminum fins are then mounted on the cooling pipes and soldered thereto in a thermal bath.

Abstract: A method of brazing metal, particularly aluminum members, is disclosed which employs gaseous bromine as a fluxing agent. The fluxing agent is introduced as an additive to a through-flowing protective or inert atmosphere in the brazing furnace.

Abstract: An improved method is disclosed for the soldering together of the cooling assembly of automobile radiators wherein aluminum fins, a first part of the cooling assembly, are etched in a solution consisting essentially of 10 to 14% sodium hydroxide, 4 to 7% zinc cyanide, 20 to 30% technical urea with the balance water for a period of 15 to 30 seconds at a temperature of 32 .degree. to 60.degree. C prior to undergoing treatment with a protective coating and eventual soldering to cooling pipes made of copper, brass, steel or aluminum, the remainder of the cooling assembly.

Abstract: An improved method for treating surfaces of aluminum sheets, and in particular, boron reinforced aluminum sheets, to render such sheets more amenable to diffusion bonding which consists in contacting the sheets prior to such diffusion bonding with an aqueous solution containing chloride ions to thereby cause etch pitting on the surfaces.

Abstract: In the production of longitudinally welded pipes, the metal strip is treated with a chemical deoxidizing agent, such as a hydrazine compound, to remove oxides from at least the strip edges, prior to arc welding, to provide an improved weld.

Abstract: The present invention is a method for constructing a solid state diffusion bonded connection which is homogeneous, capable of efficiently transmitting stress and capable of being analyzed. The method provides for the achievement of homogeneous filleted junctures which are required by long-life structural fatigue specifications. The method also provides a mechanical interlock feature which produces a fail-safe connection. By the invented method, only the amount of material required to form the desired structural connection is used. The members to be joined are cut from sheets or plates of a wrought alloy such that a predetermined amount of metal is available to produce the diffusion bond and specified filleting. Minimum force is required to produce the connection since only localized plastic flow diffusion bonding is required in the vicinity of the juncture of the members. The formed connection is homogeneous and has the same properties across the connection as the parent material.

Abstract: A method of diffusion bonding and fluxless brazing of aluminum containing components, including a method of preparing aluminum containing surfaces for such welding techniques wherein the aluminum surfaces are freed of any aluminum oxide coating and are coated with a polymeric sealer which can be thermally removed leaving essentially no residue, the polymeric sealer being removed in a substantially oxygen-free environment and the aluminum components then being brazed or diffusion bonded without the use of a flux to remove oxide coating.