Provided is a method of manufacturing a contact material, including the steps of: forming a Ni alloy film having a film thickness of 40 nm or more and 110 nm or less on a surface of WC powder having an average particle diameter of 2 m or more and 10 m or less by an electroless Ni plating method; performing heat treatment for degassing at a temperature of 500 C. or more and 860 C. or less; crushing Ni alloy-coated WC powder after the heat treatment; mixing the crushed Ni alloy-coated WC powder and Cu powder having an average particle diameter of 1 m or more and 100 m or less; and compressing the resultant mixture, followed by sintering the mixture at a temperature of more than 1,083 C. and less than 1,455 C.

An improved electrical contact alloy, useful for example, in vacuum interrupters used in vacuum contactors is provided. The contact alloy according to the disclosed concept comprises copper particles and chromium particles present in a ratio of copper to chromium of 2:3 to 20:1. The electrical contact alloy also comprises particles of a carbide, which reduces the weld break strength of the electrical contact alloy without reducing its interruption performance.

A contact assembly for an electrical device and a method for making such an assembly are presented. The contact assembly comprises a substrate and a contact material disposed on the substrate. The contact material comprises a composite material comprising a refractory material and a matrix material. The matrix material has a higher ductility than the refractory material. The composite material further comprises a core region and an outer region bounding the core region, the core region having a higher concentration of the refractory material than the outer region. The method applies cold spraying a blended feedstock to produce a layer that includes the composite material described above.

A contact assembly for an electrical device and a method for making such an assembly are presented. The contact assembly comprises a substrate and a contact material disposed on the substrate. The contact material comprises a composite material comprising a refractory material and a matrix material. The matrix material has a higher ductility than the refractory material. The composite material further comprises a core region and an outer region bounding the core region, the core region having a higher concentration of the refractory material than the outer region. The method applies cold spraying a blended feedstock to produce a layer that includes the composite material described above.

Device for making and/or breaking a current including a pair of permanent contacts (3, 4), at least one of the contacts (3, 4) being movable. At least one permanent contact (3, 4) including a main portion (3.1, 4.1) having a free end and an end protection portion (3.2, 4.2) secured to the free end of the main portion (3.1, 4.1), designed to be in mechanical and electrical contact with the other permanent contact (4, 3) only during an operation for opening or closing the pair. The end protection portion (3.2, 4.2) is made of a single transition metal having a melting temperature that is strictly higher than that of the main portion (3.1, 4.1) to which it is secured, or of an oxide or carbide of such a metal, or even of zinc oxide. For application in particular to high- or medium-voltage circuit breakers.

Device for making and/or breaking a current including a pair of permanent contacts (3, 4), at least one of the contacts (3, 4) being movable. At least one permanent contact (3, 4) including a main portion (3.1, 4.1) having a free end and an end protection portion (3.2, 4.2) secured to the free end of the main portion (3.1, 4.1), designed to be in mechanical and electrical contact with the other permanent contact (4, 3) only during an operation for opening or closing the pair. The end protection portion (3.2, 4.2) is made of a single transition metal having a melting temperature that is strictly higher than that of the main portion (3.1, 4.1) to which it is secured, or of an oxide or carbide of such a metal, or even of zinc oxide. For application in particular to high- or medium-voltage circuit breakers.

A low voltage circuit breaker is provided. The low voltage circuit breaker includes a contact system with a first contact and a second contact that are electrically connectable and disconnectable relative to one another. The first contact includes a body having a first layer and a second layer, wherein the first layer is arranged on the second layer and is configured to come in contact with the second contact for providing the electrical connection with the second contact. The first layer has a first material composition having an Ag content that is higher than an Ag content of a second material composition of the second layer. Further, the first material composition has a WC content that is lower than a WC content of the second material composition.

A circuit breaker having a monolithic structure and method of making is disclosed. The monolithic structure includes an arm portion having copper and a contact portion having a composite material. The composite material has a metallic matrix and a second phase disposed in the metallic matrix. The method of making the monolithic structure includes introducing a first powder into a first region of a mold, introducing a second powder into a second region of the mold, and consolidating the first powder and the second powder together. The first region of the mold corresponds to a contact portion, and the second region corresponds to an arm portion of the monolithic structure of the circuit breaker.

A contact assembly for an electrical device and a method for making such an assembly are presented. The contact assembly comprises a substrate and a contact material disposed on the substrate. The contact material comprises a composite material comprising a refractory material and a matrix material. The matrix material has a higher ductility than the refractory material. The composite material further comprises a core region and an outer region bounding the core region, the core region having a higher concentration of the refractory material than the outer region. The method applies cold spraying a blended feedstock to produce a layer that includes the composite material described above.

A contact assembly for an electrical device and a method for making such an assembly are presented. The contact assembly comprises a substrate and a contact material disposed on the substrate. The contact material comprises a composite material comprising a refractory material and a matrix material. The matrix material has a higher ductility than the refractory material. The composite material further comprises a core region and an outer region bounding the core region, the core region having a higher concentration of the refractory material than the outer region. The method applies cold spraying a blended feedstock to produce a layer that includes the composite material described above.