A resistance spot welding method includes the steps of: removing at least part of oil on a surface of a welding target material by energization between a pair of electrodes; and after the oil removal step, forming a nugget in an overlapped portion of the welding target material by energization between the pair of electrodes.

A welding method for a new flexible and rollable silicon-based solar module includes the following steps: cutting a cell piece into a small piece cell string including N small piece cells without splitting; cutting a hard protective layer into N small pieces according to a size of a small piece cell; allowing the cut hard protective layer to be covered on and bonded to a glue-dispensed small piece cell string to form a small string cell piece; arranging the small string cell pieces into a small standard piece according to a required size distribution, and covering the small standard piece with an adhesive film; welding positive electrodes and negative electrodes of the small standard pieces in series simultaneously to form a 1P standard part; and arranging the 1P standard parts, and fixing the 1P standard parts by bonding the adhesive films to each other to form a 5P standard part.

A welding method for a new flexible and rollable silicon-based solar module includes the following steps: cutting a cell piece into a small piece cell string including N small piece cells without splitting; cutting a hard protective layer into N small pieces according to a size of a small piece cell; allowing the cut hard protective layer to be covered on and bonded to a glue-dispensed small piece cell string to form a small string cell piece; arranging the small string cell pieces into a small standard piece according to a required size distribution, and covering the small standard piece with an adhesive film; welding positive electrodes and negative electrodes of the small standard pieces in series simultaneously to form a 1P standard part; and arranging the 1P standard parts, and fixing the 1P standard parts by bonding the adhesive films to each other to form a 5P standard part.

The present invention provides: a solid-phase spot-welding method with which the welding temperature can be controlled accurately and with which a reduction in the welding temperature can be achieved, regardless of the type of metal material being welded; and a solid-phase spot-welding device that can be used suitably in this solid-phase spot-welding method. This solid-phase welding method involves overlapping metal plate materials and carrying out spot-welding, and is characterized by having a welding preparation step in which two or more metal plate materials are held in a state in which same overlap one another, thereby forming an interface to be welded, a temperature-raising step in which a pair of electrodes are used and the interface to be welded is heated by supplying a current by a direct method, an indirect method, or a series method, thereby forming a softened region in the vicinity of the interface to be welded, and a stress application step in which an external stress greater than or equal to the yield strength of the metal plate materials at a desired welding temperature is applied to the softened region, wherein the metal plate materials are welded to each other by subjecting the softened region to local deformation.

The present invention provides: a solid-phase spot-welding method with which the welding temperature can be controlled accurately and with which a reduction in the welding temperature can be achieved, regardless of the type of metal material being welded; and a solid-phase spot-welding device that can be used suitably in this solid-phase spot-welding method. This solid-phase welding method involves overlapping metal plate materials and carrying out spot-welding, and is characterized by having a welding preparation step in which two or more metal plate materials are held in a state in which same overlap one another, thereby forming an interface to be welded, a temperature-raising step in which a pair of electrodes are used and the interface to be welded is heated by supplying a current by a direct method, an indirect method, or a series method, thereby forming a softened region in the vicinity of the interface to be welded, and a stress application step in which an external stress greater than or equal to the yield strength of the metal plate materials at a desired welding temperature is applied to the softened region, wherein the metal plate materials are welded to each other by subjecting the softened region to local deformation.

A method of resistance spot welding a steel workpiece to an aluminum or aluminum alloy workpiece involves providing a workpiece stack-up that includes a steel workpiece and an aluminum workpiece and preheating the welding electrode that is meant to contact the aluminum or aluminum alloy workpiece. The method further involves pressing the preheated welding electrode and another welding electrode against opposite sides of the workpiece stack-up, with the preheated welding electrode abutting the aluminum or aluminum alloy workpiece, and passing an electrical current between the two welding electrodes at a weld site to initiate and grow a molten weld pool within the aluminum or aluminum alloy workpiece.

A method of resistance spot welding a steel workpiece to an aluminum or aluminum alloy workpiece involves providing a workpiece stack-up that includes a steel workpiece and an aluminum workpiece and preheating the welding electrode that is meant to contact the aluminum or aluminum alloy workpiece. The method further involves pressing the preheated welding electrode and another welding electrode against opposite sides of the workpiece stack-up, with the preheated welding electrode abutting the aluminum or aluminum alloy workpiece, and passing an electrical current between the two welding electrodes at a weld site to initiate and grow a molten weld pool within the aluminum or aluminum alloy workpiece.

The present invention is provided with a roof side rail, a side outer panel that is formed of a dissimilar metal material having a higher electrical conductivity than the roof side rail, and a metal layer that is formed of the same metal material as the roof side rail and is disposed between the roof side rail and the side outer panel. Forming a nugget, which is a joint portion, between the roof side rail and the metal layer by carrying out resistance welding with the metal coating disposed between the roof side rail and the side outer panel makes it possible to accommodate the enhanced strength of an iron member and to render prepared hole processing unnecessary.

A steel sheet assembly includes a plurality of lapped steel sheets which have a tensile strength of 1,470 MPa or less and a thickness of 0.3 mm to 5.0 mm, the steel sheet assembly being formed by applying, in advance, an adhesive and a carbon-supplying agent to a surface of either or both of the steel sheets to be lapped and then welding the steel sheets. A weld of the assembly has a nugget diameter of 2.8√t (mm) or more, where t (mm) denotes the thickness of a thinner one of the steel sheets on both sides of a weld interface, and the amount of C is increased by 0.02 % by mass or more as compared to the steel sheets before being applied with the adhesive and the carbon-supplying agent.

A welding electrode apparatus has an electrode base, and electrode tip, and a locking ring that clamps the tip to the base, and that, when released, permits the tip to be replaced when worn. The locking ring and electrode tip co-operate to define an accommodation for a machine fed nut. The locking ring has a non-electrically conductive end face, and stands proud of the tip of the electrode. The locking ring has an unobstructed outside peripheral face suitable for gripping and tightening or loosening with a wrench. The locking ring has an internal, annular fluid cooling gallery and inlet and outlet ports tapped into the gallery. The cross-section of the gallery is non circular. The wall thickness of the part is roughly constant. On assembly and installation, the locking ring clamps to the tip and base, and provides a thermal conduction heat path to each of them.