Abstract: There is disclosed a precious metal article which is formed of a solid-phase sintered product of a precious metal powder. For manufacturing the precious metal article, a moldable mixture which contains a precious metal powder and a binder removable by sintering is shaped into a prescribed molded object, and the molded object is then subjected to sintering. The moldable mixture is produced by preparing a precious metal powder, preparing a jellylike cellulose binder by blending a cellulose with water and leaving for a prescribed period of time, and blending the precious metal powder and the jellylike cellulose binder together. The most preferable moldable mixture contains 50 to 90% by weight of precious metal powder, 0.8 to 8% by weight of water-soluble cellulose binder, 0.08 to 3% by weight of a surface-active agent. 0.1 to 3% by weight of oil, balance water and unavoidable impurities.

Abstract: A sputtering target of platinum-cobalt alloy is disclosed which contains 10 to 55% by weight of platinum; 1 to 15% by weight of a first additional element selected from the group consisting of nickel and tantalum; no more than 1.5% by weight of a second additional element selected from the group consisting of boron, titanium, lanthanum, cerium, neodymium, beryllium, calcium, zirconium, and silicon; no more than 20% by weight of chromium; and balance cobalt. A method for manufacturing the sputtering target is also disclosed. In the method, a platinum-cobalt alloy containing specific ingredients in predetermined amounts is first prepared. Then, the platinum-cobalt alloy is subjected to hot plastic working with a thickness reduction of no less than 30%. Subsequently, the alloy thus hot worked is subjected to a cold plastic working with a thickness reduction of no less than 5% at a temperature less than the recrystallization temperature of the alloy.

Abstract: A precious metal foil composite comprising a precious metal foil encased, by lamination, in a transparent polymeric sheet material. The composite cards produced from this composite material are used for practical purposes by encasing the above composite together with another component having opaque decorative patterns, and finally encasing the entire assembly in a secondary hard protective covering to provide the outermost protection.

Abstract: The present invention eliminates the problems associated with the use of oxygen-free copper and other high-purity copper materials as bonding wires. In accordance with one aspect of the present invention, at least one rare earth element, or at least one element selected from the group consisting of Mg, Ca, Ti, Zr, Hf, Li, Na, K, Rb and Cs, or the combination of at least one rare earth element and at least one elemented selected from the above-specified group is incorporated in high-purity copper as a refining component in an amount of 0.1-100 ppm on a weight basis, and the high-purity copper is subsequently refined by zone melting. The very fine wire drawn from the so refined high-purity copper has the advantage that it can be employed in high-speed ball bonding of a semiconductor chip with a minimum chance of damaging the bonding pad on the chip by the ball forming at the tip of the wire.In accordance with another aspect of the present invention, 0.

Abstract: The present invention eliminates the problems associated with the use of oxygen-free copper and other high-purity copper materials as bonding wires. At least one rare earth element, or at least one element selected from the group consisting of Mg, Ca, Ti, Zr, Hf, Li, Na, K, Rb and Cs, or the combination of at least one rare earth element and at least one elemented selected from the above-specified group is incorporated in high-purity copper as a refining component in an amount of 0.1-100 ppm on a weight basis, and the high-purity copper is subsequently refined by zone melting. The very fine wire drawn from the so refined high-purity copper has the advantage that it can be employed in high-speed ball bonding of a semiconductor chip with a minimum chance of damaging the bonding pad on the chip by the ball forming at the tip of the wire.

Abstract: A composite article comprising a metal substrate having a cobalt-base alloy built-up surface portion consisting essentially of a cobalt-base alloy welding metal which has been deposited on said substrate by an overlay welding process using a cobalt-base welding metal which consists essentially of 1.1 to 3.0% Si, 0.2 to 0.5% C, 25.0 to 30.0% Cr, 0.1 to 1.0% W, 0.2 to 3.0% Fe, 0.4 to 6.0% Mo, 0.1 to 2.0% MN, 1.0 to 4.0% Ni, the balance being Co and incidental impurities, the percentage being on a weight basis. The built-up surface portion has high resistance to wear and to weld cracking.

Abstract: A Cu alloy having high resistance to oxidation for use in leads on semiconductor devices is disclosed. The alloy consists essentially of 7-15 wt % Mn, 10-30 wt % Zn, 0.2-10 wt % Ni, 0.1-3 wt % Al, with the balance being Cu and incidental impurities. Also disclosed is a Cu alloy clad material wherein the substrate is made of Cu or Cu alloy having high electrical conductivity and good heat dissipation, and the cladding or partial cladding is composed of the Cu alloy having the composition specified above.

Abstract: A Cu alloy having high resistance to oxidation for use in leads on semiconductor devices is disclosed. The alloy consists essentially of 7-15 wt % Mn, 10-30 wt % Zn, 0.2-10 wt % Ni, 0.1-3 wt % Al, with the balance being Cu and incidental impurities. Also disclosed in a Cu alloy clad material wherein the substrate is made of Cu or Cu alloy having high electrical conductivity and good heat dissipation, and the cladding or partial cladding is composed of the Cu alloy having the composition specified above.

Abstract: A Cu-Ag alloy brazing filler material with low Ag content that exhibits excellent brazability and has a low vapor pressure is disclosed. The filler material comprises 5 to 35% by weight of Ag, 2.5 to 13% by weight of Si, with the balance being Cu and incidental impurities. The properties of the filler material can be improved further by addition of at least one element selected from the group consisting of Sn, In, Fe, Ni, Co, B and Li.

Abstract: A Cu-Ag alloy brazing material that exhibits excellent cold workability, brazability and has a low vapor pressure is disclosed. The filler material comprises more than 35 to 50% by weight of Ag, 2.2 to 6% by weight of Si, with the balance being Cu and incidental impurities. The properties of the filler material can be improved further by addition of at least one element selected from the group consisting of Sn, In, Fe, Ni, Co, B and Li.

Abstract: There is disclosed a method for manufacturing a stripe-patterned metal plate or composite material. Plural kinds of metal sheet blanks having different colors are placed one upon another to provide a layer structure. The metal sheets of the layer structure are bonded to each other directly and metallurgically in a solid state to provide a layer-structured plate. The layer-structured plate is cut in a direction along a face extending at a predetermined angle to a layer face thereof to provide at least one thin metal plate intermediate. The metal plate intermediate is inserted into a complementary hole formed through a solid package of metal. Then, the package containing the metal plate intermediate is hot rolled into a predetermined length with its width remaining substantially unchanged so that the metal plate intermediate is simultaneously extended at a predetermined reduction rate with its width remaining substantially unchanged.

Abstract: A process for welding a pair of thick copper plates which comprises welding the pair of copper plates with respective edges placed adjacent to each other on a backing support made of carbon at the adjacent edges in an atmosphere of an inert gas by melting a filler metal with the use of a direct current arc generated between the copper plates connected to the negative pole and a positive electrode with an arc voltage V (volt) and a welding current I (ampere) satisfying the conditions:V = 37 - 45 (1)vi>q (2)i.sup.2 /.sqroot.v < f (3)wherein Q and F are respectively determined from the equations:Q = Va Ia (4)F = Ib.sup.2 /.sqroot.Va (5)wherein Ia (ampere) is the minimum current at which a penetration to the underside of the copper plate is obtained and Ib (ampere) is the minimum current at which a blow hole is formed in the weld by the decomposition of the backing support at any voltage Va (volt) within the above stated range (1).