The present invention provides a contact member that strikes a balance between low electrical resistance and sliding durability. A contact member of the invention has a metal base and a coating disposed on at least part of the metal base. The coating contains fluorinated oil having a polar group, and metal particles surface-treated with a fluorine-based compound having a polar group.

A metal contact of a residential circuit breaker with ordered ceramic microparticles is provided. The metal contact comprises an electrical contact material comprising a metal alloy and ceramic particles to form a metal matrix composite material. Both materials the metal alloy and the ceramic particles are present together as a metal compound but without forming an alloy. The metal compound is a matrix and reinforcement being the ceramic particles such that first the ceramic particles has a sintering step to get a homogeneous preform for the metal compound being porous with a controlled size obtained by pressing a particle size of about few micrometers of the ceramic particles and then a liquid metal infiltration step to provide a homogenous distribution of the metal alloy and the ceramic particles in a three-dimensional open porous arrangement and the homogenous distribution results in ordered microstructures.

A metal contact of a residential circuit breaker with ordered ceramic microparticles is provided. The metal contact comprises an electrical contact material comprising a metal alloy and ceramic particles to form a metal matrix composite material. Both materials the metal alloy and the ceramic particles are present together as a metal compound but without forming an alloy. The metal compound is a matrix and reinforcement being the ceramic particles such that first the ceramic particles has a sintering step to get a homogeneous preform for the metal compound being porous with a controlled size obtained by pressing a particle size of about few micrometers of the ceramic particles and then a liquid metal infiltration step to provide a homogenous distribution of the metal alloy and the ceramic particles in a three-dimensional open porous arrangement and the homogenous distribution results in ordered microstructures.

The present invention provides a contact member that strikes a balance between low electrical resistance and sliding durability under the condition of load as low as about 0.1 N. A contact member of the invention has a metal base and a coating disposed on at least part of the metal base. The coating contains fluorinated oil having a polar group, and metal particles surface-treated with a fluorine-based compound having a polar group.

A silver-plated product having a higher hardness and more excellent wear resistance than those of conventional silver-plated products, and a method for producing the same. In a method for producing a silver-plated product by forming a surface layer of silver on a base material by electroplating at a current density in a silver-plating solution which is an aqueous solution containing silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and a benzimidazole (such as 2-mercaptobenzmimidazole or 2-mercaptobenzimidazole sulfonic acid sodium salt dihydrate), the ratios of the concentrations of silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and the imidazole to the current density during the silver-plating (or the ratios of the concentrations of silver potassium cyanide or silver cyanide and the imidazole to the current density during the silver plating, and the concentration of potassium cyanide or sodium cyanide) are set to be predetermined ranges, respectively.

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.

A silver-plated product is produced by forming a surface layer of silver on a base material by electroplating at a liquid temperature of 10 to 35° C. and a current density of 3 to 15 A/dm.sup.2 in a silver plating solution so as to satisfy (32.6x−300)≦y≦(32.6x+200) assuming that a product of a concentration of potassium cyanide in the silver plating solution and a current density is y (g.Math.A/L.Math.dm.sup.2) and that a liquid temperature of the silver plating solution is x (° C.), the silver plating solution containing 80 to 110 g/L of silver, 70 to 160 g/L of potassium cyanide and 55 to 70 mg/L of selenium.

A silver-plated product is produced by forming a surface layer of silver on a base material by electroplating at a liquid temperature of 10 to 35° C. and a current density of 3 to 15 A/dm.sup.2 in a silver plating solution so as to satisfy (32.6x−300)≦y≦(32.6x+200) assuming that a product of a concentration of potassium cyanide in the silver plating solution and a current density is y (g.Math.A/L.Math.dm.sup.2) and that a liquid temperature of the silver plating solution is x (° C.), the silver plating solution containing 80 to 110 g/L of silver, 70 to 160 g/L of potassium cyanide and 55 to 70 mg/L of selenium.

A silver-plated product having a higher hardness and more excellent wear resistance than those of conventional silver-plated products, and a method for producing the same. In a method for producing a silver-plated product by forming a surface layer of silver on a base material by electroplating at a current density in a silver-plating solution which is an aqueous solution containing silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and a benzimidazole (such as 2-mercaptobenzmimidazole or 2-mercaptobenzimidazole sulfonic acid sodium salt dihydrate), the ratios of the concentrations of silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and the imidazole to the current density during the silver-plating (or the ratios of the concentrations of silver potassium cyanide or silver cyanide and the imidazole to the current density during the silver plating, and the concentration of potassium cyanide or sodium cyanide) are set to be predetermined ranges, respectively.