A method for joining heat transfer plates, comprising: applying a melting depressant composition on individual application areas of a first metal sheet, each application area comprising a mid-section and two end-sections; pressing ridges and grooves in the metal sheet, the ridges extending in a direction that extends between the end-sections of the application areas, such that the application areas are located on top of the ridges; bringing the metal sheet into contact with a second, pressed metal sheet, such that contact points are formed where the mid-sections of the application areas re located; heating the sheets until melted metal is formed at the application areas where the melting depressant composition is applied; and allowing the melted metal to solidify such that a joint is obtained at the contact points.

A method for joining heat transfer plates, comprising: applying a melting depressant composition on individual application areas of a first metal sheet, each application area comprising a mid-section and two end-sections; pressing ridges and grooves in the metal sheet, the ridges extending in a direction that extends between the end-sections of the application areas, such that the application areas are located on top of the ridges; bringing the metal sheet into contact with a second, pressed metal sheet, such that contact points are formed where the mid-sections of the application areas relocated; heating the sheets until melted metal is formed at the application areas where the melting depressant composition is applied; and allowing the melted metal to solidify such that a joint is obtained at the contact points.

The invention concerns a brazing sheet comprising a core layer (5) and a braze cladding, said core layer (5) being aluminium or an aluminium alloy, said braze cladding comprising (a) a flux composite layer (2), which flux composite layer comprises a matrix of aluminium or an aluminium alloy, said matrix containing flux particles; (b) at least one filler alloy layer (1) not containing flux particles; and, (c) an aluminium or aluminium alloy layer (3) not containing flux particles, said layer forming the outermost surface of at least one side of the brazing sheet, wherein the flux composite layer (a) is positioned between said filler alloy layer (b) and said aluminium or aluminium alloy layer (c). The invention further concerns a method for its manufacturing, a cladding plate, use of the brazing sheet and a brazed heat exchanger.

An aluminium extrusion material for use in a hybrid metal extrusion and bonding process is provided. The composition of the extrusion material comprises: 0 to 0.25 wt % iron; at least 0.05 wt % dispersoid-forming elements, wherein the dispersoid-forming elements comprise 0 to 1.2 wt % manganese, 0 to 0.25 wt % chromium, 0 to 0.25 wt % zirconium and 0 to 0.25 wt % scandium; and, except when the aluminium alloy of the aluminium extrusion material is in the 2xxx series, 0 to 0.05 wt % copper. The microstructure of the extrusion material is a deformed microstructure; and the nanostructure of the extrusion material comprises an aluminium matrix with dislocations and dispersoids, and wherein the majority of the alloying elements are in solid solution in the aluminium matrix. An aluminium rod for manufacturing the extrusion material, a joint comprising a extrudate made from the extrusion material a method of manufacturing the extrusion material and the aluminium rod and a method of joining two aluminium components using the extrusion material are also provided.

An airfoil includes a first airfoil piece and a second airfoil piece that is bonded to the first airfoil piece at a joint. The first airfoil piece and the second airfoil piece are formed of aluminum alloys. At least one of the aluminum alloys is an aluminum alloy composition that has greater than 0.8% by weight of zinc. The joint includes a braze element of magnesium, zinc, or combinations thereof in a higher concentration than in other portions of the first airfoil piece and the second airfoil piece.

A method of resistance spot welding a workpiece stack-up that includes an aluminum workpiece and an overlapping adjacent steel workpiece so as to minimize the thickness of an intermetallic layer comprising FeAl intermetallic compounds involves providing reaction-slowing elements at the faying interface of the aluminum and steel workpieces. The reaction-slowing elements may include at least one of carbon, copper, silicon, nickel, manganese, cobalt, or chromium. Various ways are available for making the one or more reaction-slowing elements available at the faying interface of the aluminum and steel workpieces including being dissolved in a high strength steel or being present in an interlayer that may take on a variety of forms including a rigid shim, a flexible foil, a deposited layer adhered to and metallurgically bonded with a faying surface of the steel workpiece, or an interadjacent organic material layer that includes particles containing the reaction-slowing elements.

A method for manufacturing a heat exchanger (1) includes joining an inner fin (3) to a hollow structure (20) formed from at least two clad plates (200a, 200b) by heating and brazing a filler metal layer (B). Each clad plate has a core layer (A) composed of an aluminum alloy that contains Mg: 0.40-1.0 mass %. The filler metal layer is composed of an aluminum alloy that contains Si: 4.0-13.0 mass %, and further contains Li: 0.0040-0.10 mass %, Be: 0.0040-0.10 mass %, and/or Bi: 0.01-0.30 mass %. The inner fin is composed of an aluminum alloy that contains Si: 0.30-0.70 mass % and Mg: 0.35-0.80 mass %. A flux (F) that contains cesium (Cs) is applied along a contact part (201), and the vicinity thereof, of the at least two clad plates prior to the heating. A heat exchanger (1) may be manufactured according to this method.

An airfoil surface includes a first titanium portion, a second titanium portion, an aluminum alloy braze disposed there between, and a titanium coating covering the aluminum alloy braze, at least part of the first titanium portion and at least part of the second titanium portion.

Methods disclosed herein include using additive manufacturing to create a joint between a first metallic material and a second metallic material that is different from the first metallic material, wherein the porosity of the joint is less than about 0.1 percent by volume measured according to ASTM B-962. The additive manufacturing can be performed such that no intermetallic brittle phase forms between the first metallic material and the second metallic material.

An airfoil includes a first airfoil piece and a second airfoil piece bonded to the first airfoil piece at a joint. The first airfoil piece and the second airfoil piece are formed of aluminum alloys. At least one of the aluminum alloys is an aluminum alloy composition that has greater than 0.8% by weight of zinc.