A hollow aluminum structure that will be brazed includes at least one brazing sheet having a filler metal layer clad onto a core layer. The core layer is composed of aluminum or an aluminum alloy containing less than 0.2 mass % Mg. The filler metal layer is composed of an aluminum alloy that contains Si: 4.0-13.0 mass % and Bi: 0.01-0.3 mass %, and further contains Li: 0.004-0.08 mass % and/or Be: 0.006-0.12 mass %, the filler metal layer containing less than 0.1 mass % Mg. The hollow aluminum structure is assembled such that the filler metal layer is present at locations that will form both an interior-facing brazed joint and an exterior-facing brazed joint. Then, flux is applied onto the filler metal layer at the location that will form the exterior brazed joint, and the hollow aluminum structure heated in an inert gas atmosphere to form the interior brazed joint and the exterior brazed joint.

Provided is a heat exchanger, in particular for motor vehicles, with at least one exchanger tube of an aluminium alloy and with at least one component connected fluidically to the exchanger tube, wherein the exchanger tube and the component (14, 16) are connected to one another by way of a common soldered connection and wherein the component connected to the exchanger tube has a core layer of an aluminium alloy with the following composition: Si: max. 0.7% by weight, Fe: max. 0.70% by weight, Cu: max. 0.10% by weight, Mn: 0.9-1.5% by weight, Mg: max. 0.3% by weight, Cr: max. 0.25% by weight, Zn: max. 0.50% by weight, Ti: max. 0.25% by weight, Zr: max. 0.25% by weight, unavoidable impurities individually max. 0.05% by weight, altogether max. 0.15% by weight, the remainder aluminium.

An apparatus, material and method for forming a brazing sheet has a composite braze liner layer of low melting point aluminum alloy and 4000 series braze liner. The low melting point layer of the composite braze liner facilitates low temperature brazing and decrease of the diffusion of magnesium from the core into the composite braze liner. The reduction of magnesium diffusion also lowers the formation of associated magnesium oxides at the braze joint interface that are resistant to removal by Nocolok flux, thereby facilitating the formation of good brazing joints through the use of low temperature controlled atmosphere brazing (CAB) and Nocolok flux. The apparatus also enables the production of brazing sheet materials with high strength and good corrosion property.

An aluminum alloy brazing sheet used for brazing of an aluminum material in an inert gas atmosphere or in vacuum is formed of a two-layer material in which a brazing material and a core material are stacked. The core material is formed of an aluminum alloy and has a grain size of 20 to 300 μm, and the aluminum alloy contains Mn of 0.50 to 2.00 mass %, Mg of 0.40 to 2.00 mass %. Si of 1.50 mass % or less, Fe of 1.00 mass % or less, and Ti of 0.10 to 0.30 mass %, with the balance being aluminum and inevitable impurities. The brazing material is formed of an aluminum alloy containing Si of 4.00 to 13.00 mass % with the balance being aluminum and inevitable impurities. In a drop-type fluidity test, a ratio α (α=K.sub.a/K.sub.b) of a fluid coefficient K.sub.a is 0.50 or more.

An aluminum alloy brazing sheet formed of a brazing material, an intermediate material, a core material, and a brazing material. The intermediate material contains Mg of 0.40 to 6.00 mass % and Zn exceeding 2.00 mass % and equal to or less than 8.00 mass %. The core material contains Mg of 0.40 to 2.00 mass % and one or two or more of Mn of 1.80 mass % or less, Si of 1.50 mass % or less, Fe of 1.00 mass % or less, Cu of 1.20 mass % or less, Ti of 0.30 mass % or less, Zr of 0.30 mass % or less, and Cr of 0.30 mass % or less. Each of the core material and the intermediate material has a grain size of 20 to 300 μm, and each of the brazing materials comprises Si of 4.00 to 13.00 mass %.

A conductor for a power transmission cable has a first conductor element and a second conductor element connected by a welding joint. The welding joint has a welding material alloy where the welding material alloy has an Al content of from 90% to 98% by weight, a Ni content of from 2% to 8% by weight, and a content of other metals and/or substances from 0% to 2% by weight, based on the total weight of the welding material alloy, wherein the Al content, Ni content and content of other metals and/or substances sum up to 100% by weight.

A composition for welding or brazing aluminum comprises silicon (Si) and magnesium (Mg) along with aluminum in an alloy suitable for use in welding and brazing. The Si content may vary between approximately 5.0 and 6.0 wt %, and the Mg content may vary between approximately 0.15 wt % and 0.50 wt %. The alloy is well suited for operations in which little or no dilution from the base metal affects the Si and/or Mg content of the filler metal. The Si content promotes fluidity and avoids stress concentrations and cracking. The Mg content provides enhanced strength. Resulting joints may have a strength at least equal to that of the base metal with little or no dilution (e.g., draw of Mg). The joints may be both heat treated and artificially aged or naturally aged.

A metal matrix nanocomposite includes: (1) a matrix including an aluminum alloy; and (2) nanostmctures dispersed in the matrix, wherein the matrix includes grains having aspect ratios of about 3 or less. Manufacturing processes include subjecting the nanocomposite to solidification processing, fusion welding, extrusion, thixocasting, additive manufacturing, and heat treatment.

An aluminum alloy brazing sheet is formed of a brazing material, an intermediate material, a core material, and a brazing material. The intermediate material contains Mg of 0.40 to 6.00 mass %, and has total of contents of Mn, Cr, and Zr being 0.10 mass % or more. The core material contains Mg of 0.20 to 2.00 mass % and one or two or more of Mn of 1.80 mass % or less, Si of 1.50 mass % or less, Fe of 1.00 mass % or less, Cu of 1.20 mass % or less, Ti of 0.30 mass % or less, Zr of 0.30 mass % or less, and Cr of 0.30 mass % or less. Each of the core material and the intermediate material has a grain size of 20 to 300 μm, and each of the brazing materials contain Si of 4.00 to 13.00 mass %.

A manufacturing process of a high-strength aluminum alloy wire/strip includes the following steps: A. subjecting an alloy to smelting and spray forming to obtain a high-strength Al—Zn—Mg—Cu aluminum alloy blank; B. subjecting the blank to semi-solid upset forging to form an ingot; C. subjecting the ingot to hot extrusion and then to vacuum annealing to form a coiled material; D. subjecting the coiled material to hot continuous rolling to obtain a wire blank; and E. subjecting the wire blank to solution heat treatment, multiple stretching treatments, annealing, and multiple continuous stretching treatments to obtain the high-strength aluminum alloy wire/strip. The high-strength aluminum alloy wire/strip has the characteristics of fine and compact grains, uniform structure, clear grain boundaries, no precipitates, and no layered structure affecting the stretching performance.