AgNi20

The silver-nickel material AgNi20, also Ag80Ni20 or 80Ag20Ni, is safe against welding at inrush currents up to 100 A, has good erosion resistance with switching currents up to 100 A. It shows uniform burnup on both contact pieces (burnup residues are non-conductive) and has high hardness and thus correspondingly low mechanical wear. AgNi20 has a low contact resistance that remains nearly constant over the life of the contact, as well as good ductility, good arc migration properties, and good arc quenching properties. Wire made of this material can be welded particularly well with welding machines. Disadvantages are unfavorable burn-off properties with switching currents above 100 A, tendency to weld with inrush currents above 150 A. The AgNi20 is used in low-voltage AC and DC switching devices, for auxiliary current switches for DC and AC as well as switches for domestic appliances with nominal currents up to approx. 10 A, service switching devices for DC and AC as well as motor switches or contactors for AC up to approx for direct current, for automotive switches and relays, for circuit breakers (direct and alternating current) as well as for travel switches for railways, in particular direct current circuit breakers. AgNi20 is ductile but sensitive to sulfur. It is a machinable and roll-cladable sintered material.