This application discloses a material comprising an aluminum metal alloy cladding fusion-cast to a metal alloy core. Also disclosed is a material comprising a metal core comprising a high content of scrap metal and having two sides, a first aluminum metal cladding fusion cast to the first side of the core layer, and a second aluminum metal cladding fusion cast to the second side of the core layer. The materials can be in a form of a sheet. Sheets are roll bonded together to create permanent metallurgical bonds except at regions where a weld-stop ink is applied. The sheets are used to make corrosion resistant heat exchangers.

This application discloses a material comprising an aluminum metal alloy cladding fusion-cast to a metal alloy core. Also disclosed is a material comprising a metal core comprising a high content of scrap metal and having two sides, a first aluminum metal cladding fusion cast to the first side of the core layer, and a second aluminum metal cladding fusion cast to the second side of the core layer. The materials can be in a form of a sheet. Sheets are roll bonded together to create permanent metallurgical bonds except at regions where a weld-stop ink is applied. The sheets are used to make corrosion resistant heat exchangers.

A sacrifice positive electrode layer is formed conveniently, efficiently, and accurately on the surface of a refrigerant distributor having a complicated shape. Further, during the formation of the sacrifice positive electrode layer, the strength in the surroundings of joined parts is prevented from being lowered by excessive heating. Included are: an applying step of applying flux to remove an aluminum oxide to a surface of a plurality of outflow sections and a distributing section; an alloy disposing step of disposing a zinc-containing aluminum-silicon alloy on the surface to which the flux is applied; a forming step of forming the sacrifice positive electrode layer on the surface by heating the disposed zinc-containing aluminum-silicon alloy; a brazing material disposing step of inserting a plurality of outflow pipes into the plurality of outflow sections, respectively, and disposing an aluminum-silicon alloy brazing material on the surface of the outflow sections; and a brazing step of brazing the plurality of outflow sections with the plurality of outflow pipes, respectively, by heating the aluminum-silicon alloy brazing material.

A sacrifice positive electrode layer is formed conveniently, efficiently, and accurately on the surface of a refrigerant distributor having a complicated shape. Further, during the formation of the sacrifice positive electrode layer, the strength in the surroundings of joined parts is prevented from being lowered by excessive heating. Included are: an applying step of applying flux to remove an aluminum oxide to a surface of a plurality of outflow sections and a distributing section; an alloy disposing step of disposing a zinc-containing aluminum-silicon alloy on the surface to which the flux is applied; a forming step of forming the sacrifice positive electrode layer on the surface by heating the disposed zinc-containing aluminum-silicon alloy; a brazing material disposing step of inserting a plurality of outflow pipes into the plurality of outflow sections, respectively, and disposing an aluminum-silicon alloy brazing material on the surface of the outflow sections; and a brazing step of brazing the plurality of outflow sections with the plurality of outflow pipes, respectively, by heating the aluminum-silicon alloy brazing material.

In various embodiments, a metal alloy resistant to aqueous corrosion consists essentially of or consists of niobium with additions of tungsten, molybdenum, and one or both of ruthenium and palladium.

In various embodiments, a metal alloy resistant to aqueous corrosion consists essentially of or consists of niobium with additions of tungsten, molybdenum, and one or both of ruthenium and palladium.

A heat-dissipation substrate structure with high adhesive strength is provided. The heat-dissipation substrate structure includes a heat-dissipation base layer, a functional layer, and a matching layer. The functional layer is formed by sputtering, and has a single layer structure or a multi-layer structure. A thickness of each layer of the functional layer is less than 3 μm. The matching layer has a single layer structure or a multi-layer structure, and a thickness of each layer of the multi-layer structure of the matching layer is less than 1 μm. The matching layer is formed by sputtering of one or any two of titanium, titanium alloy, nickel, and nickel alloy. The functional layer and the heat-dissipation base layer are two heterogeneous metal layers, and the matching layer is located between the functional layer and the heat-dissipation base layer.

A metal matrix (2) for a heat exchanger (1), comprising a stack of components (4, 5, 6), in particular etched plates or corrugations (4), separator sheets (5) and bars (6), or a combination of the two types of stack, said components (4, 5, 6) being held relative to one another by layers of braze material (3), thereby ensuring the mechanical integrity of the matrix, the matrix including fluid circulation passages (10) within it, each fluid circulation passage (10) having an inner wall provided to fully contain said fluid radially, characterized in that each inner wall is fully covered with a corrosion-resistant coating (7).

Preferred application to heat exchangers based on carbon steel or stainless steel.

A metal matrix (2) for a heat exchanger (1), comprising a stack of components (4, 5, 6), in particular etched plates or corrugations (4), separator sheets (5) and bars (6), or a combination of the two types of stack, said components (4, 5, 6) being held relative to one another by layers of braze material (3), thereby ensuring the mechanical integrity of the matrix, the matrix including fluid circulation passages (10) within it, each fluid circulation passage (10) having an inner wall provided to fully contain said fluid radially, characterized in that each inner wall is fully covered with a corrosion-resistant coating (7).

Preferred application to heat exchangers based on carbon steel or stainless steel.

A method to modify the shape of a channel in a metallic substrate is described. The method includes the step of applying at least one metallic coating on selected portions of an interior surface of the channel, so as to alter the heat transfer characteristics of the channel during passage of a coolant fluid therethrough. Related articles that contain the modified channels are also described, such as gas turbine engine components.