Degussa Aktiengesellschaft

Umicore Ag & Co Kg

Umicore

Tyco Electronics Amp Gmbh

Umicore, S.a.

Te Connectivity Germany Gmbh

Saxonia Technical Materials Gmbh

Peter Braumann

Wolfgang Weise

Roger Wolmer

Andreas Koffler

Willi Malikowski

Bernd Kempf

Ralf Hoffmann

Dan V Goia

Peter Sandeck

Sebastian Fritzsche

Jens Heinrich

Werner Roth

Martin Wieberger

Ralf Niederreuther

Allen Molvar

Thierry Charles Simon Vandevelde

Andreas Koch

Gunther Wiehl

The present invention relates to a novel process for producing metal composites by internal oxidation.

Oxidation method

The present invention relates to a method for producing an electric contact element from a semifinished product and to the electric contact element and the corresponding semifinished product. The method for producing an electric contact element (), which can be electrically contacted by a mating contact, comprises the following steps: producing a wire () from a first electrically conductive material (); coating the wire surface with a sheath () made of a second electrically conductive material; partially removing the sheath () in a direction along a longitudinal wire axis (); forming at least one cylindrical semifinished product () by dividing the wire in a direction transverse to the longitudinal wire axis; fixing the semifinished product on a contact carrier () such that the second electrically conductive material is connected to the contact carrier; and reshaping the welded semifinished product so as to form the contact element (), wherein a contact area (), which is accessible for a mating contact, is formed by the first electrically conductive material.

Electric contact element and method for producing an electric contact element

The invention is directed to a process for manufacture of fine precious metal containing particles, specifically silver-based particles and silver-based contact materials via an intermediate silver(+1)-oxide species. The process comprises in a first step the formation of a thermally instable silver (+1)-oxide species by adding a base to an aqueous silver salt solution comprising an organic dispersing agent. Due to the presence of the organic dispersing agent, the resulting silver (+1)-oxide species is thermally instable, thus the species is decomposing to metallic silver at temperature lower than 100&#xb0; C. The process optionally may comprise the addition of a powdered compound selected from the group of inorganic oxides, metals, and carbon-based compounds. Furthermore the process may contain additional separating and drying steps. The process is versatile, cost efficient and environmentally friendly and is used for the manufacture of silver-based particles and electrical contact materials. Silver nanoparticles made according to the process are characterized by a narrow particle size distribution. Electrical contact materials manufactured according to the process reveal improved contact welding properties.

Process for manufacture of silver-based particles and electrical contact materials

Sintered silver-iron material for electrical contacts, with properties comparable with those of silver-nickel materials, is obtained by using iron powder having more than 0.25% carbon by weight and microhardness higher than 200 HV 0.025 and sintering in a hydrogen-free protective gas.

Sintered silver-iron material for electrical contacts and process for

Silver-iron materials for electrical switching contacts with properties which come very close to those of silver-nickel materials formed of 0.5 to 4.5% by weight iron and 0.05 to 2% by weight of one or more of the oxides magnesium oxide, calcium oxide, yttrium oxide, lanthanum oxide, titanium oxide, zirconium oxide, hafnium oxide, cerium oxide, niobium oxide, tantalum oxide, chromium oxide, manganese oxide, iron oxide, zinc oxide, aluminum oxide, indium oxide, silicon oxide, and tin oxide, the balance being silver.

Silver-iron material for electrical switching contacts (I)

Silver-iron materials for electrical switching contacts with properties which come very close to those of silver-nickel materials formed of 4.6 to 15% by weight iron and 0.05 to 5% by weight of one or more of the oxides magnesium oxide, calcium oxide, yttrium oxide, lanthanum oxide, cerium oxide, chromium oxide, iron oxide, aluminum oxide, indium oxide, silicon oxide, and tin oxide, the balance being silver.

Silver-iron material for electrical switching contacts (II)

An electrical contact material for switching rated currents between 20 and 100 Ampere having improved operational life made of 3.2 to 19.9 wt-% tin oxide and 0.05 to 0.4 wt-%, in each case, of indium oxide and bismuth oxide, the remainder being silver. In the course of the manufacture of the material by powder metallurgy more than 60 wt-% of the tin oxide should exhibit a particle size of more than 1 .mu.m.

Sintering material containing silver-tin oxide for electrical contacts

Silver-iron materials for electrical switching contacts with properties which come very close to those of silver-nickel materials formed of 0.5 to 20% by weight iron 0.5 to 5% by one or more of the elements rhenium, iridium, and ruthenium, and 0.05 to 2% by weight of one or more of the oxides magnesium oxide, calcium oxide, yttrium oxide, lanthanum oxide, titanium oxide, zirconium oxide, hafnium oxide, cerium oxide, niobium oxide, tantalum oxide, chromium oxide, manganese oxide, iron oxide, zinc oxide, copper oxide, aluminum oxide, indium oxide, silicon oxide, and tin oxide, the balance being silver.

Silver-iron material for electrical switching contacts (III)

Electrical contacts are formed from a silver-iron material which contains 3 to 30% by weight of iron and one or more of the components manganese, copper, zinc, antimony, bismuth oxide, molybdenum oxide, tungsten oxide or chromium nitride in amount totalling 0.05 to 5 weight percent, the balance being silver. These materials are suitable for forming electrical contacts of a wide variety. Tantalum is an optional component which may also be utilized particularly when 0.2 percent to 2 percent zinc is present.

Growing community of inventors

Alzenau, Germany

Peter Braumann