A junction structure includes a first material that is a metallic material, a third material that is a metallic material and is weldable to the first material, and a second material which is a nonferrous metallic material or a nonmetallic material. The second material is sandwiched and fixed between the first material and the third material by lap joining. At least one of the first material or the third material has a weld zone where the first material and the third material are melted and joined together, and at least one exhaust groove or at least one exhaust hole around the weld zone. The at least one exhaust groove or the at least one exhaust hole penetrates a thickness of the at least one of the first material or the third material.

A junction structure includes a first metallic material, a second material different in type from the first metallic material, and a welding wire as a third material similar to the first metallic material. The second material is stacked on the first material. The molten metal of the third metallic material is deposited by arc welding into the through part of the second material so as to form a flanged or tapered bead, so that the first and third metallic materials and the second material are fixed together.

The invention relates to a method for manufacturing a sandwich panel as a semi-finished product where at least one layer of a non-metallic material is positioned between at least two metallic layers. At least one of the metal layers is shaped into a three dimensional layer, and the metal layers are in direct mechanical contact to enable resistance weldability of the semi-finished product in order to connect the semi-finished product to a desired combination of solutions in a subsequent manufacturing process.

A welding method for joining a first plate made of a material other than steel and a second plate made of steel includes a step of making a hole through each of the first plate and the second plate, a press-fitting step, an overlapping step, and a filling and welding step. A shaft portion of a joining assist member being solid, being made of steel, and having an outer shape with step having the shaft portion and a flange portion is press-fitted in the hole of the first plate. The first plate and the second plate is overlapped such that the shaft portion faces the hole of the second plate. The hole of the second plate is filled with a weld metal and the second plate and the joining assist member are welded.

To solve the problem about the difference in temperature increasing rate between an overlapped part and a one-sheet part so as to further improve the corrosion resistance of plating after hot stamping. An overlapped blank for hot stamping includes: a first steel sheet; and at least one second steel sheet connected to a surface of the first steel sheet via a welding point and smaller in area than the first steel sheet, wherein: the first steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the first steel sheet, and the second steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the second steel sheet; a coating weight of the aluminum-based plated layer on the first steel sheet is W1 (g/m.sup.2) in terms of an average coating weight on both the faces; a coating weight of the aluminum-based plated layer on a surface on a side not in contact with the first steel sheet in the second steel sheet is W2 (g/m.sup.2); and each of the W1 and the W2 is within a range of 20 g/m.sup.2 or more and 120 g/m.sup.2 or less, and satisfies relationships of Expression (1) and Expression (2).

A weld is formed in a workpiece such as a pipeline by first activating a melting device, such as a laser, to form a molten weld pool in the workpiece and then activating a welding device, such as a GMAW torch, to initiate a weld in the weld pool. The weld therefore incorporates the weld pool homogeneously. Relative movement between the activated welding device and the workpiece continues and completes the weld while the melting device remains deactivated.

To solve the problem about the difference in temperature increasing rate between an overlapped part and a one-sheet part so as to further improve the corrosion resistance of plating after hot stamping. An overlapped blank for hot stamping includes: a first steel sheet; and at least one second steel sheet connected to a surface of the first steel sheet via a welding point and smaller in area than the first steel sheet, wherein: the first steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the first steel sheet, and the second steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the second steel sheet; a coating weight of the aluminum-based plated layer on the first steel sheet is W1 (g/m.sup.2) in terms of an average coating weight on both the faces; a coating weight of the aluminum-based plated layer on a surface on a side not in contact with the first steel sheet in the second steel sheet is W2 (g/m.sup.2); and each of the W1 and the W2 is within a range of 20 g/m.sup.2 or more and 120 g/m.sup.2 or less, and satisfies relationships of Expression (1) and Expression (2).

The invention pertains to a welding apparatus, particularly to a spot sa welding apparatus which utilizes a single welding electrode/torch to weld vertically adjacent metallic sheets or plates together. The apparatus comprises a MAG welding apparatus with a welding torch and shielding inert or semi-inert gases gas source configured to protect the welded working place, an apparatus for creating holes in at least one of the welded metallic sheets and at least one frame part for assembling the MAG welding apparatus and apparatus for creating holes.

A weld is formed in a workpiece such as a pipeline by first activating a melting device, such as a laser, to form a molten weld pool in the workpiece and then activating a welding device, such as a GMAW torch, to initiate a weld in the weld pool. The weld therefore incorporates the weld pool homogeneously. Relative movement between the activated welding device and the workpiece continues and completes the weld while the melting device remains deactivated.

Provided is a joint of a copper terminal and an aluminum conductor. A copper terminal connecting member of the joint is connected to a conductive core of the aluminum conductor by means of a transition welding layer, and the joint can also be provided with a reinforcing welding layer. Further provided is a method for preparing the joint using plasma arc welding. According to the invention, the connection portion of the copper terminal with the aluminum conductor is filled with solder in a plasma arc welding manner, such that copper and aluminum are connected by means of the solder. Damage to an aluminum oxide layer during welding increases the conductivity and can also isolate the copper terminal and the aluminum conductor, thus preventing an electrochemical reaction between the copper and the aluminum.