Abstract: The invention relates to a brazing sheet product comprising a core sheet, a clad layer on said core sheet made of an aluminum alloy containing silicon in an amount in the range of 4 to 14% by weight, an optional layer comprising nickel on the outersurface of said clad layer, and a diffusion layer comprising nickel-tin alloy on the outer surface of said nickel layer. The invention further relates to a method of manufacturing such a brazing product comprising the process step of plating different metal layers and subjecting the plated brazing product to an annealing treatment by holding the plated brazing product at a temperature in the range of 100 to 500° C. for a period of 1 sec. to 300 minutes to form a diffusion layer comprising nickel-tin alloy on the outer surface of said layer comprising nickel.

Abstract: The invention relates to a brazing sheet product including a core sheet, on at least one side of the core sheet a clad layer of an aluminum alloy including silicon in an amount in the range of 4 to 14% by weight, and further including on at least one outersurface of the clad layer a plated layer of nickel-tin alloy, such that the clad layer and all layers exterior thereto form a metal filler for a brazing operation and have a composition with the proviso that the mol-ratio of Ni:Sn is in the range of 10:(0.5 to 9).

Abstract: A method for applying a metal layer onto at least one surface of an aluminium or aluminium alloy workpiece, including the steps of pretreating the surface and applying the metal layer by plating, wherein the pretreating step includes a non-electrolytic treatment by immersion of the workpiece in a single acidic solution, preferably a sulphuric acid solution, having a temperature of at most 100° C. A brazed assembly comprising at least one component of an aluminium workpiece made by this method is also disclosed.

Abstract: A brazing product, e.g. a brazing sheet product, having an aluminium layer made of an aluminium alloy comprising silicon in an amount in the range of 2 to 18 weight %, and a layer comprising nickel on the outer surface of the aluminium layer such that taken together the aluminium layer and all layers exterior thereto form the filler metal for a brazing operation. The filler metal has a composition containing at least one element: (i) with a smaller exchange current density for the Hydrogen Evolution Reaction (“HER”) than nickel and/or (ii) such that the electro-chemical potential difference between particles of Ni-aluminide(s) of the filler and the aluminium alloy matrix of the filler is reduced. The filler metal's mol-ratio of Ni to such element(s) is in the range of 10:(0.3-30). The invention also relates to a method of manufacturing a brazed assembly using the brazing product, and to a brazed assembly comprising at least one component made of the brazing product.

Abstract: The invention relates to a brazing sheet product including a core sheet, on at least one side of the core sheet a clad layer of an aluminum alloy including silicon in an amount in the range of 4 to 14% by weight, and further including on at least one outersurface of the clad layer a plated layer of nickel-tin alloy, such that the clad layer and all layers exterior thereto form a metal filler for a brazing operation and have a composition with the proviso that the mol-ratio of Ni:Sn is in the range of 10:(0.5 to 9).

Abstract: A method for applying a metal layer onto at least one surface of an aluminium or aluminium alloy workpiece, including the steps of pretreating the surface and applying the metal layer by plating, wherein the pretreating step includes a non-electrolytic treatment by immersion of the workpiece in a single acidic solution, preferably a sulphuric acid solution, having a temperature of at most 100° C. A brazed assembly comprising at least one component of an aluminium workpiece made by this method is also disclosed.

Abstract: A brazing product, e.g. a brazing sheet product, having an aluminium layer made of an aluminium alloy comprising silicon in an amount in the range of 2 to 18 weight %, and a layer comprising nickel on the outer surface of the aluminium layer such that taken together the aluminium layer and all layers exterior thereto form the filler metal for a brazing operation. The filler metal has a composition containing at least one element: (i) with a smaller exchange current density for the Hydrogen Evolution Reaction (“HER”) than nickel and/or (ii) such that the electro-chemical potential difference between particles of Ni-aluminide(s) of the filler and the aluminium alloy matrix of the filler is reduced. The filler metal's mol-ratio of Ni to such element(s) is in the range of 10:(O.3-30). The invention also relates to a method of manufacturing a brazed assembly using the brazing product, and to a brazed assembly comprising at least one component made of the brazing product.

Abstract: The invention relates to a method of manufacturing an Al or Al alloy workpiece, including the steps of (a) providing an Al or Al alloy workpiece, (b) pre-treating of the outersurface of the Al or Al alloy workpiece, and (c) plating a metal layer including nickel onto the outersurface of the pre-treated Al or Al alloy workpiece. During step (c) the metal layer including nickel is deposited by electroplating both nickel and bismuth using an aqueous bath comprising a nickel-ion concentration in a range of 10 to 100 g/l and a bismuth-ion concentration in the range of 0.01 to 10 g/l. The invention further relates to an aqueous plating bath for use in the method of this invention.

Abstract: A brazing sheet product and a method of manufacturing a brazing sheet product in which a layer comprising nickel is plated onto a surface of a clad layer made of an aluminium-silicon alloy containing silicon in the range of 2 to 18 weight %, wherein the surface is pre-treated by application of a bonding layer comprising zinc or tin. The application of the bonding layer may be by a zincate or a stannate treatment. The use of lead to promote wetting during brazing can be reduced or avoided, or other elements such as bismuth can be used.

Abstract: A brazing sheet product and a method of manufacturing a brazing sheet product in which a layer comprising nickel is plated onto a surface of a clad layer made of an aluminium-silicon alloy containing silicon in the range of 2 to 18 weight %, wherein the surface is pre-treated by application of a bonding layer comprising zinc or tin. The application of the bonding layer may be by a zincate or a stannate treatment. The use of lead to promote wetting during brazing can be reduced or avoided, or other elements such as bismuth can be used.

Abstract: The invention relates to a method of manufacturing an Al or Al alloy workpiece, including the steps of (a) providing an Al or Al alloy workpiece, (b) pre-treating of the outersurface of the Al or Al alloy workpiece, and (c) plating a metal layer including nickel onto the outersurface of the pre-treated Al or Al alloy workpiece. During step (c) the metal layer including nickel is deposited by electroplating both nickel and bismuth using an aqueous bath comprising a nickel-ion concentration in a range of 10 to 100 g/l and a bismuth-ion concentration in the range of 0.01 to 10 g/l. The invention further relates to an aqueous plating bath for use in the method of this invention.

Abstract: A method for applying a zinc layer onto an aluminum or aluminum alloy sheet, comprising pretreating the surface and applying the layer by electrolytic galvanizing, the pretreating comprises electrochemical graining of the surface, for example in a solution having a pH less than 3 with an alternating current applied between the sheet and an electrode. In an alternative method, the pretreating includes applying a preliminary zinc layer by immersing the surface in a zinc-containing alkaline solution, applying a potential to the sheet and reversing the polarity of said potential at least once. The sheets are useful for building cladding sheets and automotive panels.

Abstract: An improved electrochemical dissolution process for electrochemically dissolving a first metal by simultaneously creating hydrogen evolution at a second metal. The second metal is a metal that has a larger current exchange density for hydrogen evolution than the first metal, and both metals are immersed in an aqueous electrolyte system, wherein the first metal and the second metal are galvanically coupled. By taking measures to reduce inhibition of the hydrogen evolution at the second metal, the rate of dissolution of the first metal is enhanced. The measures to reduce the inhibition comprise selecting suitable temperatures and concentrations of the electrolyte, dividing the electrolyte into two fluids coupled by a selectively permeable device and selecting suitable resistance value for a connecting means electrically connecting the first and the second metal. The invention is particularly useful for removing Zn or Sn from Zn- or Sn-containing steel scrap.