Abstract: A method for making a bimetallic or trimetallic electrical contact. Features that only its shank portion, made of copper or copper alloy, is covered by a thin layer of silver or silver alloy for protecting the shank portion from environmental erosion. This shank portion is made by cutting the silver-plated wire to a short piece.

Abstract: A bimetallic or trimetallic electrical contact, only its shank portion being made of copper or copper alloy and being covered by a thin layer of silver or silver alloy for protecting the shank portion from environmental erosion. Said shank portion is preferably made by cutting silver-plated wire to a short piece.

Abstract: Novel Ag-SnO-CdO electrical contact materials are disclosed, which are made of ternary Ag alloys consisting of more than 5-12 weight % of Sn, 0.5-5 weight % of Cd, and a balance of Ag, the alloys having been prepared by melting and having been internal oxidized. Novel manufacturing methods are also disclosed, in which internal-oxidation is conducted in an oxygen atmosphere of more than 10 atm to 200 atm, at a temperature of 750.degree. C. to 500.degree. C., and at a condition that the alloys are kept at a solid phase not involving any liquid phase.

Abstract: Electrical contact materials are made by the internal-oxidation of Ag alloys containing more than 5 weight % of Sn, with the assistance of Pb or Zr contained at an amount as minimum as possible. Complete and uniform internal-oxidation of said Sn contents are obtained primarily on account of the internal oxidation conducted at an elevated oxygen atmospheric pressure, that is, 10 to 150 atm.

Abstract: Electrical contacts especially for use with electric breakers, consisting of (1) a base made from a silver-tin system alloy containing In, and (2) a clad over the base made from a silver-cadmium system alloy, the alloys having been internally oxidized. The clad (2) stands by to initial tests provided for electric breakers, and the base (1) stands by to the tests thereafter. The base has no segregation of tin oxides on account of internal oxidation of the base screened by the clad (2).

Abstract: Internal oxidized Ag-SnO system alloy electrical contact materials having a moderate initial contact resistance and having no depletion layer is disclosed. The alloy is internal oxidized by having it sandwiched between pure silver thin layers, and is cut horizontally right in two, simultaneously removing the depletion layer from the internally oxidized alloy.

Abstract: Ag-SnO system alloy electrical contact materials. The Ag alloy before internal oxidation thereof contains Sn of an amount of 5-20 weight %, 0.5-15 weight % of which amount is in the powder form of SnO.sub.2. The existence of SnO.sub.2 particles in the alloy accelerates the internal oxidation speed, allowing oxygen to readily pass aside and between the particles, while the internal oxidation per se makes the alloy more dense by eliminating spaces between SnO.sub.2 grain particles on account of the volumeric expansion of Sn which results from the internal oxidation thereof.

Abstract: Internal oxidized Ag-SnO system alloy electrical contact materials having a moderate initial contact resistance and having no depletion layer is disclosed. The alloy is internal oxidized by having it sandwiched between pure silver thin layers, and is cut horizontally right in two, simultaneously removing the depletion layer from the internally oxidized alloy.

Abstract: Electrical contact materials made from an internally oxidized Ag alloy containing 0.5 to 12 weight % of Sn. Internal oxidized structures which have been produced in the alloy at the forwardmost area along a progressive direction of internal oxidation and which are fine and free from the segregation of tin oxides, are employed as contact surfaces. Another surface opposite to said contact surfaces may be brazeable by having it subjected to a reduction or decomposition treatment of metal oxides about said another surface.

Abstract: A method for preparing cores and the like such as magnetic recording head cores. They are made from metallic alloy oxides such as ferrite and used as electric, electronic, or magnetic elements of electric appliances such as tape recorders and televisions. The method is characterized by covering alloy compacts in part or as whole by silver and then baking them in an oxygen atmosphere for a predetermined time and at a predetermined temperature, whereby constituents of the alloy compacts are converted to oxides under strict control. Silver converging baked cores may be utilized for attaching terminals.

Abstract: Internally oxidized Ag-Sn-Bi alloy electrical contact materials. The alloy contains a larger amount of Bi, viz., more than 2 weight percent of bismuth, whereby the Bi which can not be a solid solution with Ag and Sn and hence precipitates as a numerous number of defects in an Ag matrix, does not allow said Ag matrix to form crystalline grains, but accelerates oxidation velocity and has solute metals oxidized extremely in minute and uniform up to inner cores of alloy mass.

Abstract: Electrical contact materials of a silver base which have dispersed in their silver matrices 2-20 weight % of either one of or combination of fine oxide grains of Sn, Sb, Zn, In, and Bi, and which materials are diffused at their contact surfaces and for moderate depths adjacent thereto with Au, Pd, or alloys thereof, which gradually diminish in diffusion density from the contact surfaces to the moderate depths of the contact materials. The precious metal thus diffused in solid phase about the contact surfaces prevents their chemical aging and improves electrical performance such as anti-weldability, contact resistance, and endurance, without scattering from the contact surfaces or melting deeply all together into the matrices of the contact materials, and further without isolating from and coagulating spherically on the contact surfaces, even when they are subjected to electric arcs.

Abstract: The overlaying of a Fe-containing metallic material such as stainless steel which constitutes an anti-abrasive and sweat-proof base for decorative articles and ornaments, with a precious metal alloy such as a gold 18 carats fine which contains Ag is made by at least two steps, viz.; a first step which comprises plating selected surfaces of the base material with the constituents of said alloy but excluding Ag constituent in any desired order and one at a time in a plurality of first successive layers, and heating said first layers to cause them to diffuse to each other and with the base material; and a second step which comprises plating said surfaces further with all or selected ones of the constituents of said alloy and including the primary and Ag constituents in any desired order and one at a time in a plurality of second successive layers, and heating the second layers to cause them to diffuse to each other and with the first layers.

Abstract: An aggregate and/or integrate comprising of silver and tin oxides and/or tin alloy oxides of 4-25 weight % which have been prepared to have the oxides disperse uniformly in the silver, are subjected to a temperature about the melting point of silver, whereby an electrical contact material made from said aggregate and/or integrate comes to have a continuous silver matrix as if produced by an internal oxidation method and also to have such uniform dispersion of the metal oxides in said silver matrix which is comparable or superior to that producible by a powder metallurgical method. The contact material has an excellent elongation and high conductivity.

Abstract: Immediately after a composite electric contact is made from wires by cold welding and in a manner as it has been cold welded, it is brought onto a supporting metal and subjected to pressure and resistance heat exerted by a pair of electrodes whereby the contact and the supporting metal are spot welded in situ without adversely affecting the supporting metal such as warping thereof and whereby cold welded abutting ends of the contact are released from stress which is produced by cold welding and the contact is annealed in whole.

Abstract: Two or more pieces of wire of precious and non-precious metals are cold welded at their free ends, for producing a composite electrical contact or contact material, contact surface of which is made of said precious metal or alloys thereof. One of, a plurality of, or all of said free ends are provided with one or more projections of a diameter less than that of the wires which are expanded and flow under welding pressure over the abutting surfaces of the free ends to form bonded surfaces of wires without undesired or unexpected expansion of the wire pieces in their diameters.

Abstract: Internally oxidized Ag-Sn of 3 - less than 5 weight % alloy electrical contact materials are improved of their internal oxidation velocity and consequently of their contact resistance by the addition of 0.01-0.1 weight % of Bi. The alloy may comprise 0.01-0.5 weight % of one or more elements of the iron family.