A contact for a vacuum interrupter of a low, medium or high-voltage switchgear includes a contact rod composed of a first electrically conductive material and extending along a longitudinal axis of the contact, and a contact piece composed of a second electrically conductive material and fastened to an end face of the contact rod. The contact rod and the contact piece are materially bonded to one another at a connecting face. At least one of the contact rod or the contact piece has a wall which delimits the connecting face, rises perpendicularly to the longitudinal axis and is disposed such that the contact piece and the contact rod are also force-lockingly connected to one another by a force acting transversely to the longitudinal axis between the contact piece and the contact rod. A production method for such a contact is also provided.

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 μm or more and 10 μm 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 μm or more and 100 μm 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.

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 μm or more and 10 μm 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 μm or more and 100 μm 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.

The present disclosure aims to provide an electrical contact to which a low boiling point metal is added, the electrical contact being able secure both mechanical strength and conductivity at the same time. The electrical contact according to the present disclosure includes a base material made of Cu, particles of a high melting point substance dispersed in the base material, the particles being made of at least one of a high melting point metal or a carbide of the high melting point metal, and Te and Ti dispersed in the base material, wherein, the Te of 3.5 to 14.5 mass % is added where the total is 100 mass %, and Ti/Te is 0.12 to 0.38.

The present disclosure aims to provide an electrical contact to which a low boiling point metal is added, the electrical contact being able secure both mechanical strength and conductivity at the same time. The electrical contact according to the present disclosure includes a base material made of Cu, particles of a high melting point substance dispersed in the base material, the particles being made of at least one of a high melting point metal or a carbide of the high melting point metal, and Te and Ti dispersed in the base material, wherein, the Te of 3.5 to 14.5 mass % is added where the total is 100 mass %, and Ti/Te is 0.12 to 0.38.

Switch assemblies and switching methods are disclosed. In some embodiments, a switch assembly may include a first blade having a first contact within an enclosed cavity, and a second blade having a second contact within the enclosed cavity. The first and second contacts are operable to make or break contact with one another in response to a magnetic field. The switch assembly may further include a coating formed over each of the first and second contacts, the coating including a titanium layer, a second layer formed over the titanium layer, and a tungsten-copper layer formed over the second layer. In some embodiments, the second layer is copper or molybdenum.

Switch assemblies and switching methods are disclosed. In some embodiments, a switch assembly may include a first blade having a first contact within an enclosed cavity, and a second blade having a second contact within the enclosed cavity. The first and second contacts are operable to make or break contact with one another in response to a magnetic field. The switch assembly may further include a coating formed over each of the first and second contacts, the coating including a titanium layer, a second layer formed over the titanium layer, and a tungsten-copper layer formed over the second layer. In some embodiments, the second layer is copper or molybdenum.

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.

The present invention is a clad material for an electric contact, including a base material composed of a Cu-based, precipitation-type age-hardening material, and a contact material composed of an Ag alloy bonded to the base material. On a bonded interface between the contact material and the base material, a width of a diffusion region including Ag and Cu is 2.0 μm or shorter. The clad material is produced by bonding each other the contact material and the base material having undergone solutionizing and age-hardening beforehand, suppressing the diffusion region from expanding after bonding. The present invention is capable of providing an electric contact, which achieves higher conductivity, without sacrificing property of the Cu-based, precipitation-type age-hardening material.