Abstract: A method of manufacturing a composite contact in which a flange section with a large diameter at an end of a base part with a small diameter, the composite contact having: a contact section which is made from silver alloy into an upper-surface part of the flange section; and a leg section which is made from copper alloy by forming a large-diameter part so as to form a lower-surface part of the flange section is made integrally with the base part, having the steps of: a primary-forming process forging a copper-alloy wire and a silver-alloy wire having a smaller diameter than that of the copper-alloy wire in a hole of a forming die in a state of being butted to each other so as to form a primary-formed body including a silver-alloy part and a copper-alloy part so that the wires are bonded with each other.

Abstract: Disclosed is an electrical contact having high electrical conductivity for a compact electromagnetic relay including an internally oxidized silver-oxide material which is prepared by subjecting an Ag alloy having a composition consisting essentially of, by weight, 5.1 to 9% Sn, 1.5 to 5% In, and 0.005 to 0.06% Bi, with the balance being Ag and unavoidable impurities, to an internal oxidation treatment and then subjecting to a heat treatment for diffusion, aggregation, and growth of precipitated oxides, wherein the internally oxidized silver-oxide material has a metallographic structure such that coarse grains of composite oxides are dispersed and distributed in an Ag matrix, the coarse grains of composite oxides being formed as a result of coarsening of ultra-fine grains of Sn-based oxides and ultra-fine grains of In-based oxides, which are precipitated by the internal oxidation treatment, by the heat treatment for diffusion, aggregation, and growth of the precipitated oxides.

Abstract: Disclosed is an electrical contact having high electrical conductivity for a compact electromagnetic relay including an internally oxidized silver-oxide material which is prepared by subjecting an Ag alloy having a composition consisting essentially of, by weight, 5.1 to 9% Sn, 1.5 to 5% In, and 0.005 to 0.06% Bi, with the balance being Ag and unavoidable impurities, to an internal oxidation treatment and then subjecting to a heat treatment for diffusion, aggregation, and growth of precipitated oxides, wherein the internally oxidized silver-oxide material has a metallographic structure such that coarse grains of composite oxides are dispersed and distributed in an Ag matrix, the coarse grains of composite oxides being formed as a result of coarsening of ultra-fine grains of Sn-based oxides and ultra-fine grains of In-based oxides, which are precipitated by the internal oxidation treatment, by the heat treatment for diffusion, aggregation, and growth of the precipitated oxides.