Abstract: Contact pad designed to be fixed on a movable contact of a low-voltage circuit breaker designed to withstand peak short-circuit currents comprised between 200 and 600 amperes per square millimeter of pad. The pad is made of a silver- or copper-based conducting material alloy, a fraction of refractory particles such as tungsten carbide, tungsten or titanium nitride and a fraction of carbon fibers. The weight percentage of carbon fibers in the pad is strictly less than 2% of the total weight of the pad.

Abstract: Two solid copper pieces are assembled by welding without filler metal. The pieces both have a projection which are placed facing and in contact with one another, before the pieces to be assembled are placed on the welding press. Welding is performed by passing a very high intensity current for a short period of about one tenth of a second under very high pressure. The welding operation prevents any annealing of the copper.

Abstract: A connection process by welding a braided strip to a contact finger defined by side by side stacking of two elementary blades. The first blade is provided with a semi-open notch cooperating with the juxtaposed flat face of the second blade to define a housing receiving a compacted end of the braided strip, said end being hot encrusted in the housing by welding under pressure, without local deformation of the blades. The second blade comprises an overspill aperture located facing the notch to enable the molten copper from the compacted end to be transferred during the welding operation, the surface of the aperture being smaller than that of the notch. Assembly is performed in a single operation without addition of solder.

Abstract: A contact part is shaped to form a cavity in which a sintered or agglomerated block is placed before the assembly is placed on a welding press causing fixing and shaping of the block to form the contact pad. The protuberance of the pad may result from a deformation of the support in the course of the fixing operation, by a pin supported by the electrode of the welding machine coming up against the face opposite to the pad of the support.

Abstract: A coating in the form of a silver-based foil or strip is fixed onto a protuberance of a contact finger by resistance brazing while applying a force to crush the protuberance which constitutes the foundation of the strip.

Abstract: Several braids (26) to connect a moving contact (10) to a lug (14) for the current lead are attached to the lug by welding under pressure, the ends (32) of the braids (26) being placed in slots (34, 36, 38) made in the face of the lug (14). The welding occurs without any need of hard solder.