A circular blank made of a steel plate is lapped onto an Al-based plate in lapped areas of the Al alloy plate and another steel plate. Then, the three members are pressed by a pair of electrodes, and a welding current is allowed to flow between both the electrodes, thereby sequentially performing the melting of a current-supplied portion of the Al alloy plate and a portion near the current-supplied portion, the elimination of a molten portion by a partial bulgy deformation of the blank toward the Al alloy plate, the abutment of the bulgy deformed portion against the steel plate, and the resistance-welding between the bulgy deformed portion and the steel plate.

Process for lap joining two kinds of metallic members having different melting points

A design of copper welding electrode is disclosed. The electrode can be used in successive spot welding operations on assembled aluminum alloy sheet parts of widely varying thicknesses, e.g., from 0.9 to 4+ mm. The electrode has a round body terminating in a truncated cone with a crowned face. The face has a diameter of about eleven millimeters up to the diameter of the body and the radius of the crowned face is about twenty to thirty millimeters. The dimensions and shape of the electrode provide robust welding performances despite varying part thicknesses and off angle electrode positioning, and the textured surface provides good electrical contact.

Welding electrode for aluminum sheets

The invention relates to a clamping device for components to be joined (B1, B2), said device comprising: a) a first component holder (1) for a first component (B1); b) a second component holder (5) for a second component (B2); and c) a clamping structure (10), which fixes the component holders (1, 5) in a joining position in relation to one another. When the component holders (1, 5) are in the joining position, the clamping structure (10) extends from an outer face of the first component holder (1) to an outer face of the second component holder (5) facing away from the outer face of the first component holder (1) and surrounds a respective peripheral edge of said component holders (1, 5).

Clamping device for holding and clamping components

A moving die is held by a robot and made to approach a vehicle, and a positioning pin is inserted into a positioning hole of the vehicle. The moving die is brought into a floating state of being displaceable relative to the vehicle by reducing a force of the robot for maintaining an attitude thereof. In a state of holding the moving die by the robot, a surface of the moving die is brought into contact with the vehicle by an adsorbing mechanism including an adsorbing portion of an elastic member provided to the moving die. The moving die and the robot are cut to be separated.

Hemming working method and working apparatus

The purpose is to provide a joined body of dissimilar materials comprising steel material and aluminum material, which can be obtained by spot welding with high joining strength; and a spot welding method therefor. A joined body (3) is obtained by spot welding a particular thick steel material (1) and an aluminum material (2). The area of a nugget (5) in a spot weld is determined in relation to the plate thickness of the aluminum material (2). The area of the portion of a boundary reaction layer (6) having a thickness of 0.5-10 μm in the nugget (5) is determined in relation to the plate thickness of the aluminum material (2), and high joining strength is obtained.

Joined body of dissimilar materials comprising steel material and aluminum material, and joining method therefor

The present invention relates to a resistance welding method suitable for use in spot welding between a steel-base metal sheet, which has been plated for rust prevention purposes, and an aluminum-base metal sheet and aims to permit a current to flow at a high density across the plated steel sheet and the aluminum-clad steel sheet, thereby realizing high-quality welding. An aluminum-clad steel sheet comprised of a steel layer having projections and an aluminum layer is interposed between the plated steel sheet and the aluminum-base metal sheet to be welded to each other. An electrode is energized by a predetermined weld current from an alternating power supply. The current path is limited to the area of the projections, and metallic melt formed by melting of the plating is accommodated between the projections, preventing the current-carrying area from being increased. Consequently, the temperature of the interface of the plated steel sheet and the aluminum-clad steel sheet can be efficiently raised, resulting in the formation of a proper nugget on both sides of the aluminum-clad steel sheet.

Method and material for resistance welding steel-base metal sheet to aluminum-base metal sheet

PURPOSE: To provide a roller hemming device by which a lower die, its exchange and storage place are unnecessitated and by which roller hemming is performed highly efficiently and at low cost CONSTITUTION: The roller hemming devices 2 is one that the lower die of a conventional device is dispensed with and instead of it a receiving roller 48 is installed which holds a work W and receives hemming working force, constituting a pair of roller mechanisms 6 with a pressing roller 44 in between A mechanism 26 for imparting pressing force for example is installed in the pressing roller 44, and the flange W22 of the work W, which is held by a work holding device 18, is inserted between the receiving roller 48 and the pressing roller 44 In this state, the work holding device 18 is moved along a preliminarily instructed locus by the operation of a three-dimensional moving robot 10 The flange W22 of the work W is continuously passed between the pressing roller 44 and the receiving roller 48, and it is surely hemming-worked by a prescribed pressing force while the hemming working force is surely received by the receiving roller 48 COPYRIGHT: (C)1995,JPO

Roller hemming device

PURPOSE: To keep the high strength of a joint in the wide current range by using the iron/aluminum clad of the prescribed ratio of the thickness of a sheet made of aluminum to that of the steel sheet. CONSTITUTION: A galvanized steel sheet 1 is arranged on the iron side c>f a clad sheet of double layer of iron/aluminum made of a cold-rolled steel sheet 3 and an aluminum sheet 4, and an aluminum sheet 2 is arranged on the aluminum sheet 4 side to execute the spot welding. The iron/aluminum clad sheet where the ratio of the thickness of the aluminum sheet to that of the steel sheet is 1:1.3-1:5.0 is used, and the welding is executed under the condition where the welding current is 7.5-15.5A, and the welding time is 80-280ms. This constitution suppresses the deposition of the aluminum and the plating to the minimum, and high strength of the joint can be secured. COPYRIGHT: (C)1995,JPO

Method and material for resistance welding of dissimilar metal

Widerstandsschweissverfahren für stahl- und aluminium-metallplatten und widerstandsschweissmaterial

PURPOSE:To carry out a high quality welding by applying a high density current between a plated steel material and a clad material in a resistance welding method being suitable to a spot welding between the steel material executing a corrosion preventing treatment, etc., with a plating work and an aluminum base material. CONSTITUTION:The clad material 15 composed of an iron layer 15a having projecting parts 15c and an aluminum layer 15b is interposed between the plated steel plate 13 as a material to be welded and the aluminum steel plate 14. A specified current is applied to the electrodes 10, 11 from AC electric source 15b. Electric conducting passage of the welding current is limited to the area of the projecting parts 15c, and as molten plating metal by melting the plating layer 13a is incorporated among the pitches of the projecting parts 15c, the enlargement of the electric current conducting area is prevented. In this result, the temp. of the interface between the plated steel plate and the clad material is efficiently raised and the suitable nugget is formed to both surfaces of the clad material 15.

Katsutoshi Ueno

Papers

Method and material for resistance welding steel-base metal sheet to aluminum-base metal sheet

Roller hemming device

Method and material for resistance welding of dissimilar metal

Widerstandsschweissverfahren für stahl- und aluminium-metallplatten und widerstandsschweissmaterial

Method for resistance welding plated steel material and aluminum base material and clad material