The present invention relates to a method for producing and/or repairing wear-stressed recesses or openings on components (22) of a turbomachine, especially of elements of a flow passage boundary, and also to corresponding components, wherein the method comprises: producing an at least two-layer molded repair part (15), one layer (2) of which is formed by an Ni-solder and a further layer (3) of which is formed from a mixture of an Ni-solder (4) and hard material particles (5) of hard alloys on a base of cobalt or nickel and which at least partially has an outer shape which is complementary to the inner shape of the recess (20) or opening which is to be repaired, inserting the molded repair part (15) into the recess (20) or opening and at least partially heat-treating the component (22) for soldering the molded repair part (15) onto the component.

Use of an aluminium composite material in a thermal joining method, said material consisting of at least one aluminium core alloy and at least one external brazing layer consisting of an aluminium brazing alloy provided on one or both sides of the aluminium core alloy, wherein the aluminium brazing layer has a pickled surface. Reduced costs and a lower environmental impact is achieved by using an aluminium composite material in which the pickled surface of the aluminium brazing layer had been pickled by pickling with an acid, aqueous pickling solution containing at least one mineral acid and at least one complex-forming agent or a complexing mineral acid, wherein the removal of material in the pickling is between 0.05 g/m.sup.2 and 6 g/m.sup.2, the aluminium composite material is used in a flux-free, thermal joining method, and the joining method is carried out in the presence of a protective gas.

An electrical joint structure including a substrate, a multi-layer bonding structure, and a blocking layer is provided. The multi-layer bonding structure is present on the substrate and includes a diffusive metal layer and a tin-rich layer. The diffusive metal layer includes a copper-tin alloy on a surface of the diffusive metal layer. The surface faces the substrate. A thickness of the copper-tin alloy is less than or equal to 2 m. The tin-rich layer is present on and in contact with the diffusive metal layer. The blocking layer is present between the multi-layer bonding structure and the substrate and at least in contact with a part of said copper-tin alloy, such that the multi-layer bonding structure is spaced apart from the substrate.

A bonding material having a first layer containing Sn as a main component thereof and a second layer containing a metal having a higher melting point than that of Sn as a main component thereof, wherein the first layer and the second layer are laminated on each other, and an amount of Sn in the first layer is larger than a stoichiometric amount of Sn that forms an intermetallic compound between the Sn and the metal.

A bonded structure, including a Zn-based brazing filler metal and a Cu-based bonding object bonded to each other, wherein the bonded structure includes a joint including a first alloy phase, a second alloy phase and a third alloy phase between the Zn-based brazing filler metal and the Cu-based bonding object, wherein the second alloy phase is formed at an interface between the first alloy phase and the third alloy phase, and wherein, in a cross section parallel to a bonding direction, a ratio of the second alloy phase at the interface between the first alloy phase and the third alloy phase is less than 80%.

A brazing sheet is provided for use in brazing performed in an inert gas atmosphere both using flux and without using flux. The brazing sheet includes an aluminum-based core, an intermediate material layered on the core and being composed of an aluminum alloy that contains Mg: 0.40-3.0 mass %, and a filler metal layered on the intermediate material and being composed of an aluminum alloy that contains Si: 6.0-13.0 mass % and Mg: less than 0.050 mass %. The brazing sheet satisfies the formula below where M [mass %] is the Mg content in the intermediate material, ti [m] is the thickness of the intermediate material, and tf [m] is the thickness of the filler metal:
tf10.15ln(Mti)+3.7.

Brazing sheet having a core layer made of a first aluminium alloy, attached to one side of said core layer a sacrificial cladding made of a second aluminium alloy, and attached to the other side of said core layer a braze cladding made of a third aluminium alloy. The first aluminium alloy consists of: Si 0.6 wt %; Fe 0.7 wt %; Cu 0.4-0.9 wt %; Mn 1.0-1.6 wt %; Mg 0.2 wt %; Cr 0.05-0.15 wt %; Zr 0.05-0.15 wt %; Ti 0.05-0.15 wt %; other elements 0.05 wt % each and 0.2 wt % total; Al balance up to 100 wt %; the second aluminium alloy consists of: Si 0.65-1.0 wt %; Fe 0.4 wt %; Cu 0.05 wt %; Mn 1.4-1.8 wt %; Zn 1.5-4.0 wt %; Zr 0.05-0.20 wt %; other elements 0.05 wt % each and 0.2 wt % total; Al balance up to 100 wt %. The third aluminium alloy has a melting point lower than said first and second aluminium alloys.

This aluminum alloy brazing sheet is provided with: a core material comprising 2.0 mass % or less (including 0 mass %) of Mg and a remainder of Al and unavoidable impurities; and a brazing material comprising Si, Bi, Mg, and a remainder of Al and unavoidable impurities. The aluminum alloy brazing sheet satisfies the expressions 3C.sub.Si13, 0.13C.sub.Mg.sup.0.3C.sub.Bi0.58C.sub.Mg.sup.0.45, C.sub.Mg-b0.1, and 0.2C.sub.Mg1.1 when the Si content of the brazing material is denoted by C.sub.Si, the Bi content of the brazing material is denoted by C.sub.Bi, the Mg content of the brazing material is denoted by C.sub.Mg-b, the Mg content of the core material is denoted by C.sub.Mg-c, and C.sub.Mg=C.sub.Mg-b+C.sub.Mg-c/2.

Provided is an aluminum alloy clad material including an aluminum alloy core material, an intermediate layer material that is clad on one surface of the core material, and a first brazing filler metal that is clad on a surface of the intermediate layer material, the surface not being on the core material side, wherein the core material, the intermediate layer material, and the first brazing filler metal each include an aluminum alloy having a predetermined composition, the existence density of AlMn based intermetallic compounds having a circle-equivalent diameter between 0.1 and 1.0 m inclusive in the intermediate layer material before brazing heating is at least 1.010.sup.5 pieces/mm.sup.2, and the existence density of AlMn based intermetallic compounds having a circle-equivalent diameter between 0.1 and 1.0 m inclusive in the intermediate layer material after brazing heating is at least 1.010.sup.4 pieces/mm.sup.2. Further provided is a method for producing the aluminum alloy clad material.

An aluminum alloy brazing sheet used for brazing aluminum, without using a flux, in an inert gas atmosphere or vacuum is formed by arranging a brazing material on one side or both sides of a core material made of pure aluminum or aluminum alloy, the brazing material including 6% to 13% by mass of Si and the balance being Al and inevitable impurities, and performing cladding with an intermediate material interposed between the core material and the brazing material, the intermediate material including 0.01% to 1.5% by mass of Bi, 1.5% to 13% by mass of Si, and the balance being Al and inevitable impurities, the intermediate material having a thickness of 2% to 35% of a thickness of the brazing material, wherein one or both of the intermediate material and the core material includes 0.4% to 6% by mass of Mg.