An aluminum heat exchanger includes first and second plates with inner and outer surfaces, which are joined by brazing and define at least one fluid flow passage. The first and second plates each comprise a core layer of aluminum or an aluminum alloy having a melting temperature greater than an aluminum brazing temperature. The first plate also includes a first outer clad layer defining the outer surface of the first plate. The first outer clad layer is solderable to a metal layer of an object to be cooled and includes nickel or copper. A second outer clad layer is located between the first outer clad layer and the core layer and is roll bonded to at least the second outer clad layer. A manufacturing method includes brazing first and second plates, where the layers of the first plate are roll bonded and the first plate is optionally formed before brazing.

A heat exchanger includes: a main body; and a tube sheet that is bonded to the main body with a brazing material and is used to fix the main body to a support by a fixing member. The tube sheet includes: a bonding surface to which the brazing material is applied; a rising portion that rises from the bonding surface; and a through-hole through which the fixing member is passed. The through-hole is opened at the rising portion, penetrates the tube sheet, and has an inner peripheral surface to which the brazing material is not applied. The main body includes heat transfer tubes through which refrigerant flows, and the tube sheet is bonded to surface of the heat transfer tube.

A radiator structure is provided. The radiator structure includes a substrate, a first metal coating layer and a second metal coating layer. The first metal coating layer and the second metal coating layer are made of materials different from one another, and are formed on the substrate by different processes. The first metal coating layer is a non-first masking area formed on the substrate by wet processing. The second metal coating layer is a non-second masking area correspondingly formed on the first metal coating layer and the substrate by sputtering. A first masking area and a second masking area are not necessarily the same.

A heat-dissipation substrate having a gradient sputtered structure includes at least two layers. A first layer is a heat-dissipation base layer, and a second layer is a gradient sputtered layer that is bonded onto the heat-dissipation base layer by gradient sputtering. An outermost surface layer of the gradient sputtered layer is a functional layer, and the gradient sputtered layer contains a main component of the heat-dissipation base layer and that of the functional layer. A percentage of the main component of the functional layer contained in the gradient sputtered layer monotonically increases or strictly monotonically increases along a direction from the heat-dissipation base layer toward the functional layer, and a percentage of the main component of the heat-dissipation base layer contained in the gradient sputtered layer monotonically increases or strictly monotonically increases along a direction from the functional layer toward the heat-dissipation base layer.

Provided are new aluminum alloys for use as one or more cladding layer(s) in clad aluminum alloy products for brazing applications. The cladding layer(s) include constituents that break and remove the oxide film on metal parts to be joined to produce high-strength brazing joints without the use of corrosive flux. Also provided herein are corrosion-resistant aluminum sheet packages including one or more of the aluminum alloy cladding layer(s) and an aluminum alloy core.

Provided is a metal matrix nanocomposite comprising: (a) a metal or metal alloy as a matrix material; and (b) multiple graphene sheets that are dispersed in said matrix material, wherein said multiple graphene sheets are substantially aligned to be parallel to one another and are in an amount from 0.1% to 95% by volume based on the total nanocomposite volume; wherein the multiple graphene sheets contain single-layer or few-layer graphene sheets selected from pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, doped graphene, chemically functionalized graphene, or a combination thereof and wherein the chemically functionalized graphene is not graphene oxide. The metal matrix exhibits a combination of exceptional tensile strength, modulus, thermal conductivity, and/or electrical conductivity.

A process for producing an amorphous ductile brazing foil is provided. According to one example embodiment, the method includes providing a molten mass, and rapidly solidifying the molten mass on a moving cooling surface with a cooling speed of more than approximately 10.sup.5° C./sec to produce an amorphous ductile brazing foil. A process for joining two or more parts is also provided. The process includes inserting a brazing foil between two or more parts to be joined, wherein the parts to be joined have a higher melting temperature than that the brazing foil to form a solder joint and the brazing foil comprises an amorphous, ductile Ni-based brazing foil; heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint; and cooling the heated solder joint, thereby forming a brazed joint between the parts to be joined.

The present invention relates to a process for the production of an aluminium multilayer brazing sheet which comprises a core layer made of a 3xxx alloy comprising 0.1 to 0.25 wt. % Mg, a brazing layer made of a 4xxx alloy on one or both sides of the core layer, and optionally an interlayer between the core layer and the brazing layer on one or both sides of the core layer, the process comprising the successive steps of: providing the layers to be assembled or simultaneous casting of the layers to obtain a sandwich; rolling of the resulting sandwich to obtain a sheet; and treating the surface of the sheet with an alkaline or acidic etchant.

A coating composition for a heat exchanger tube including vanadium (V), a flux, and a binder, wherein the vanadium is included in an amount of 28 to 38 parts by weight with respect to 100 parts by weight of the composition, and a coating method of a heat exchanger tube using the same are provided.

Iron-based braze filler alloys having unexpectedly narrow melting temperature ranges, low solidus and low liquidus temperatures, as determined by Differential Scanning calorimetry (DSC), while exhibiting high temperature corrosion resistance, good wetting, and spreading, without deleterious significant boride formation into the base metal, and that can be brazed below 1,100 C contains a) nickel in an amount of from 0% to 35% by weight, b) chromium in an amount of from 0% to 25% by weight, c) silicon in an amount of from 4% to 9% by weight, d) phosphorous in an amount of from 5% to 11% by weight, e) boron in an amount of from 0% to 1% by weight, and f) the balance being iron, the percentages of a) to f) adding up to 100% by weight. The braze filler alloys or metals have sufficient high temperature corrosion resistance to withstand high temperature conditions of Exhaust Gas Recirculation Coolers.