Abstract: A heat exchanger and method of assembly for an automotive vehicle includes at least one tube having an internal surface and an external surface, and a composition cladding having at least magnesium applied to the internal surface and external surface of the tube.

Abstract: A method for fluxless brazing of unclad aluminum includes forming first and second components to be joined of unclad aluminum; etching selected surface areas of the components; depositing an elemental metal on the selected surface areas; abutting the first and second components along the etched surfaces forming a junction; applying an aluminum filler about the junction; and heating the components and filler and bonding the components and filler.

Abstract: A method is disclosed of making a braze sheet for a brazed assembly. The method includes the steps of providing a sheet of a core material and a composition cladding and mechanically embedding a flux into the sheet.

Abstract: A heat exchanger and method of assembly for an automotive vehicle includes at least one tube having an internal surface and an external surface, and a composition cladding having at least magnesium applied to the internal surface and external surface of the tube.

Abstract: A method of thermally spraying a coating onto the interior of a cylindrical surface which coating is graded between enhanced optimal machinability and enhanced wear resistance.

Abstract: A method of bonding a thermally sprayed coating to a non-roughened light metal (i.e. cast aluminum-based) surface. The method comprises the steps of (a) depositing a flux material (i.e. potassium aluminum's fluoride containing up to 50 molar % other fluoride salts) onto such cast surface which has been cleansed to be substantially free of grease and oils, such deposition providing a dry flux coated surface, the flux being capable of removing oxide on the cast surface and having a melting temperature below that of the cast surface; (b) thermally activating the flux in the flux coated surface to melt and dissolve any oxide residing on the cast surface; and (c) concurrently therewith or subsequent to step (b) thermally spraying metallic droplets or particles onto the flux coated surface to form a metallic coating that is metallurgically bonded to the cast surface.

Abstract: Method of depositing an Fe.sub.x O comprising coating onto a light metal substrate by use of wire-arc thermal spraying that propels atomized droplets by use of atomizing gases, comprising: preparing at least one surface of the light metal substrate to present an exposed essentially non-oxidized substrate surface; and thermally spraying melted droplets of a steel feedstock wire onto the prepared surface by use of propellant gases to deposit a composite coating, the gases being controlled as to content to regulate the exposure of the droplets to oxygen so that Fe.sub.x O is substantially the only iron oxide formed during spraying, x being 0.5-1.5.

Abstract: An automotive exhaust manifold is fabricated from stainless steel sheet metal of thin dense gauge, and provided with an outer coating of less dense stainless steel or other suitable material spray bonded to it to provide an irregular surface of non-uniform cross-section with a large surface area to damp the transmission of sound waves from the manifold.

Abstract: A method of preparing metal surfaces for thermally applied coatings by electrical discharge, which method controllably provides greater roughness for increased mechanical coating adhesion, avoids carbon deposits and is more economical to use. The method comprises melting and rapidly solidifying globules of the metal surface by spark erosion, the spark erosion occurring by incidence of an electrical discharge between an electrode and the metal surface closely spaced thereto, the spacing having an electrolyte with plasma forming capabilities, the discharge resulting from application of an electrical current to the electrode with a DC voltage in the range of 60-85 volts and amperage in the range of 50-110 amps, the current being pulsed on for periods of 150-300 micro seconds per spark.

Abstract: An improved method of brazing of two unclad aluminum shapes, particularly for automotive heat exchangers, which brazing joint does not leave a physically apparent layer of brazing material and which effects a stronger, sounder autogenous joint. A thin film of aluminum eutectic forming material (Si, Al-Si or Al-Zn) is deposited onto a zone of at least one of the shapes to be brazed or joined. The shapes are placed in joining relationship to form an assembly with a joint at the zone. The assembly is heated to a temperature to diffuse the eutectic forming material into the aluminum members to form a sacrificial bond between the shapes at the joining zone. It is desirable that at least one of the unclad aluminum shapes to be joined is extruded tubing having a precise diametrical configuration and said film is deposited as a physically vapor deposited layer in a thickness range of 1-50 microns.

Abstract: A method of thermally spraying a solid lubricant (i.e. graphite or BN) impregnated metal matrix onto a metal target, using the steps of: (a) creating a flame or arc into which a consummable strand is fed, the strand being constituted as a hollow sheath of metal and a core therein comprising essentially solid lubricant powder particles, the flame or arc melting the metal of such strand; (b) applying a pressurized jet of atomizing gas to the melt and included graphite particles to project a spray of molten heavy metal and graphite particles generally homogeneously distributed throughout such spray, said graphite being protected against ablation during transit from the flame or arc to the target; and (c) surface heat treating essentially only the deposit to precipitate additional graphite while densifying the metal and controlling microstructure.

Abstract: A method of the thermally spraying a solid lubricant (i.e. graphite or BN) impregnated metal matrix onto a metal target, using the steps of: (a) creating a flame or arc into which a consummable strand is fed, the strand being constituted as a hollow sheath of metal and a core therein comprising essentially solid lubricant powder particles, the flame or arc melting the metal of such strand; (b) applying a pressurized jet of atomizing gas to the melt and included graphite particles to project a spray of molten heavy metal and graphite particles generally homogeneously distributed throughout such spray, said graphite being protected against ablation during transit from the flame or arc to the target; and (c) surface heat treating essentially only the deposit to precipitate additional graphite while densifying the metal and controlling microstructure.