The invention provides a switching electrode which has a small variation in resistance value even when a large amount of current is repeatedly cut off and can carry a stable amount of current even when it is continuously used. In the invention, the switching electrode is used in a switch which includes a first switching electrode tip (21) and a second switching electrode tip (22), brings the first switching electrode tip (21) and the second switching electrode tip (22) into surface contact with each other to carry a current, and separates the first switching electrode tip (21) and the second switching electrode tip (22) to cut off the current. At least one of contact surfaces of the first switching electrode tip (21) and the second switching electrode tip (22) is a flat surface having an uneven portion.

An apparatus and method for fastening layers of non-ferrous alloys, like aluminum, magnesium and copper utilizes a steel fastener and a spot welding machine. The fastener and metals are stacked and the heat from the welder's electric current softens the lower melting point aluminum allowing the fastener to penetrate the aluminum. A weld zone between the fastener and the various layers creates an internal weld. The fastener has a rough shaft that is coated by the molten weld zone and is hard to withdraw on solidification. Layers of non-conductive materials like plastics and ceramics may also be affixed to a conductive layer using a fastener made from a compatible material that extends through a pilot hole and welds to or penetrates a conductive layer. The fastener may have projections that initially reduce contact area with the stack.

A method for joining components includes providing a first component where the first component is an aluminum die-cast component and has a joining region for disposing and fastening a second component, generating at least in regions an adhesive layer on the joining region by a thermal spraying method, and fastening the second component to the adhesive layer by joining by pressure welding.

A resistance spot welding method includes sandwiching metal plates put on top of one another between a pair of electrodes and performing resistance spot welding sequentially on a plurality of welding points close to each other on the metal plates by performing a current application between the electrodes so as to join the metal plates to each other. A welding current value to form a welding nugget at a welding point to be subjected to the resistance spot welding second or later among the welding points is set to be higher than a first welding current value to form a first welding nugget at a first welding point to be subjected to the resistance spot welding first among the welding points.

A welding electrode for use in resistance spot welding an assembly of overlying metal workpieces that includes an aluminum alloy workpiece is disclosed. The welding electrode includes a body, a convex weld face at one end of the body, and ringed protrusions that project outwardly from the convex weld face. The ringed protrusions are positioned to make contact with, and indent into, a surface of the aluminum alloy workpiece when the convex weld face is pressed against the aluminum alloy workpiece during a spot welding event. When brought into contact with the surface of the aluminum alloy workpiece, the ringed protrusions disrupt the oxide film present on the aluminum alloy workpiece surface, which improves the spot welding process.

A welding electrode for use in engaging an aluminum alloy workpiece during a spot welding process has a weld face that includes a base surface and a plurality of circular ridges that project outwardly from the base surface. The circular ridges are blunted, and their presence on the weld face provides the first welding electrode with several useful capabilities, including the ability to establish better mechanical and electrical contact with the aluminum alloy workpiece.

A golf club head comprising at least one part manufactured via a metal injection molding process, and attached to another part of the golf club head via electrical resistance welding, is disclosed herein. The present invention is also directed to a method of making said golf club head, the method comprising the steps of providing a first golf club head part made from a first metal material, metal injection molding a second golf club head part from a second, different metal material, and electrical resistance welding the second golf club head part to the first golf club head part to form a combined part.

An equipment main bod includes an intermediate electrode set disposed between upper and lower welding electrodes and provided at at least one of the upper and lower welding electrode sides. The intermediate electrode set includes a plurality of intermediate units, each intermediate unit having an intermediate electrode set jig and an intermediate electrode attachable to and detachable from the intermediate electrode set jig, and is configured as a rotary type in which the plurality of intermediate units are provided so as to be rotatable in a circumferential direction such that the plurality of intermediate units sequentially stop at a welding position that is aligned with the upper and lower welding electrodes in an up-down direction. The intermediate electrode set is configured to resistance-weld the workpiece, while pressing the workpiece by the pressing unit, via the intermediate electrode of the intermediate unit at the welding position.

A domed copper electrode tip has a refractory insert inserted thereinto extending from the apogee of the dome into the interior of the electrode. The refractory insert is, preferably, a tungsten insert which is force-fitted into the interior of the electrode tip.

The present invention provides a welding electrode capable of spot-welding a workpiece having a surface oxide film with stable welding quality, the welding electrode allowing general tip dressers to be used. The welding electrode of the present invention is used for spot welding of a workpiece. The welding electrode includes an end face provided so as to contact the workpiece, and at least one elongated groove provided in the end face or a plurality of blind holes provided in the end face. A depth of the groove or a depth of the blind holes is 0.5 mm or more and 20 mm or less. A ratio (d/w) of the depth d of the groove to a width w of the groove or a ratio (d/s) of the depth d of the blind holes to a size s of the blind holes is 2 or more.