A method for producing an overlap composite material from sheet metal is described, wherein a first sheet (1) of a first metal and a second sheet (2) of a second metal, which has a lower strength than the first metal, are positioned one above another in an overlapping manner in an edge region, and are then joined by rolling. In accordance with the invention, provision is made for the first sheet (1) to have a wedge-shaped edge in cross-section, and for the second sheet (2) to be positioned with its edge on a side surface (3) of the first sheet (1) formed by the wedge-shaped edge, wherein the side surface (3) formed by the wedge-shaped edge of the first sheet (1) has a greater width than the side surface (4) of the edge of the second sheet (2) positioned on the said side surface (3) of the first sheet (1), and, after positioning, the sheets (1, 2) are joined by rolling.

A method for producing an overlap composite material from sheet metal is described, wherein a first sheet (1) of a first metal and a second sheet (2) of a second metal, which has a lower strength than the first metal, are positioned one above another in an overlapping manner in an edge region, and are then joined by rolling. In accordance with the invention, provision is made for the first sheet (1) to have a wedge-shaped edge in cross-section, and for the second sheet (2) to be positioned with its edge on a side surface (3) of the first sheet (1) formed by the wedge-shaped edge, wherein the side surface (3) formed by the wedge-shaped edge of the first sheet (1) has a greater width than the side surface (4) of the edge of the second sheet (2) positioned on the said side surface (3) of the first sheet (1), and, after positioning, the sheets (1, 2) are joined by rolling.

A lead material (5) for a negative electrode is made of a clad material (50) including a Cu layer (51) made of Cu or a Cu alloy and Ni layers (52, 53) each made of Ni or a Ni alloy. The Ni layers are respectively bonded to opposite surfaces of the Cu layer. The Ni layers each include a surface (52b, 53b) not bonded to the Cu layer, the surface including an oxide film (52c, 53c) with a thickness of 30 nm or less.

A process and apparatus for forming a structure comprising: a) forming a pack from a skin sheet and a core sheet, b) placing the pack in a mould and heating the pack; c) injecting a first gas between the core and skin sheets to urge the skin sheet against the mould; d) injecting a second gas on the side of the core sheet remote from the skin sheet to urge the core sheet against the skin sheet; e) maintaining gas pressure of the second gas thereby diffusion bonding the sheets; and f) injecting a third gas between the skin sheet and the mould, to force the skin sheet against the core sheet.

A metal foil bonding device (50) for bonding pieces of metal foil (2) on the successively conveyed sheet-shaped electrodes (1) on the conveyor plates (20) is provided. When it is detected that there is an abnormality in a piece of metal foil (2) to be bonded to the sheet-shaped electrode (1) on the conveyor plate (20) next conveyed to the metal foil bonding device (50), the conveyor plate (20) next conveyed to the metal foil bonding device (50) is temporarily stopped right before the metal foil bonding device (50).

A metal foil bonding device (50) for bonding pieces of metal foil (2) on the successively conveyed sheet-shaped electrodes (1) on the conveyor plates (20) is provided. When it is detected that there is an abnormality in a piece of metal foil (2) to be bonded to the sheet-shaped electrode (1) on the conveyor plate (20) next conveyed to the metal foil bonding device (50), the conveyor plate (20) next conveyed to the metal foil bonding device (50) is temporarily stopped right before the metal foil bonding device (50).

The present invention relates to a process for modifying the fluorine distribution in a hydrocarbon compound, comprising a step of placing in contact between a hydrocarbon compound and a catalytic composition comprising a chromium-based catalyst, said process being performed in a reactor made of a material comprising a base layer made of a material M1 and an inner layer made of a material M2, said base layer and said inner layer being laid against each other, characterized in that the material M2 comprises at least 80% by weight of nickel on the basis of the total weight of the material M2, advantageously at least 90% by weight, preferably at least 95% by weight, in particular at least 99% by weight of nickel on the basis of the total weight of the material M2.

Disclosed herein is an article comprising a first metal layer; a second metal layer that is chemically different from the first metal layer; and a third metal layer disposed between the first metal layer and the second metal layer and contacting both the first metal layer and the second metal layer; where the third metal layer is chemically similar to either the first metal layer or the second metal layer; where at least two metal layers that are chemically similar are welded together through a clearance opening located in a metal layer that is not chemically similar to the at least two metal layers.

Disclosed herein is an article comprising a first metal layer; a second metal layer that is chemically different from the first metal layer; and a third metal layer disposed between the first metal layer and the second metal layer and contacting both the first metal layer and the second metal layer; where the third metal layer is chemically similar to either the first metal layer or the second metal layer; where at least two metal layers that are chemically similar are welded together through a clearance opening located in a metal layer that is not chemically similar to the at least two metal layers.

[Problem] To provide: a roil-bonded body which is able to be suppressed in waviness in the surface; and a method for producing this roil-bonded body. [Solution] A roll-bonded body according to the present invention is obtained by bonding a first metal layer and a second metal layer with each other by means of rolling, and is characterized in that the surface of the first metal layer has an arithmetic average waviness (Wa.sub.1) 0.01-0.96 and a maximum waviness height (Wz.sub.1) of 0.2-5.0 m.