Degussa Aktiengesellschaft

Umicore Ag & Co Kg

Umicore

Tyco Electronics Amp Gmbh

Degussa - Huls Ag

Dmc2 Degussa Metals Catalysts Cerdec Ag

Umicore, S.a.

Te Connectivity Germany Gmbh

Saxonia Technical Materials Gmbh

Bernd Kempf

Werner Groll

Peter Braumann

Andreas Koffler

Dan V Goia

Roger Wolmer

Hans-Martin Ringelstein

Doris Hathaway

Gernot Schoeck

Werner Roth

Stefan Wieland

Ralf Hoffmann

Monika Berweiler

Andreas Freund

Peter Sandeck

Werner Kuhn

Rudi Steinke

Sebastian Fritzsche

Georg Ptaschek

Jens Heinrich

Alexander Voelcker

Barbara Bender

Gernot Schock

Ulrich Birkholz

Martin Wieberger

Ernst Drost

Hans Martin Ringelstein

Bernd Meier

Gunther Wiehl

Andreas Koch

Ralf Niederreuther

Stefan Schittny

Ulrich Kump

Gerlinde Gantert

Klaus-Peter Gundlach

Allen Molvar

Thierry Charles Simon Vandevelde

Carsten Boehme

Inge Fallheier

Meike Roos

Roland Fuchs

Calogero DiVicenzo

Frank Silze

Daniel Schnee

Helmut Ries

Steven Thierolf

Sebastian Starck

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

The invention relates to a process for producing a material based on silver-carbon, that involves the steps of: (i) providing a suspension of carbon particles; and (ii) supplying a solution of a silver compound and of a reducing agent, such that a silver-containing precipitate is deposited onto the carbon particles, where the carbon particles have a mean diameter of 200 nm or greater. The invention further relates to a material obtainable by this process and to the use of the material in circuit breakers for low-voltage power engineering.

Silver/carbon-based material and method for producing the same for contact material

The present invention relates to a method for manufacture of silver-based composite powders for electrical contact materials. The invention relates also to electrical contact materials made from such composite powders. The process comprises a high energy dispersing process of wet silver oxide (AgO) with additional second oxide components in aqueous suspension. The high energy dispersing process can be conducted by high shear mixing or by high energy milling. Preferably high speed dispersing units working at rotating speeds in the range of 5,000 to 30,000 rpm or high energy mills such as attritor mills are used. The new process is versatile, economical and offers access to a broad spectrum of contact materials. The silver-based composite powders made according to the new process yield contact materials with a highly dispersed microstructures and superior material characteristics.

Process for manufacture of silver-based composite powders for electrical contact materials and composite powders so produced

The invention relates to a process and a device () for the production of spherical metal particles () from a melt (). In order to produce droplets a melt jet () is subjected to vibrations and is led through at least one nozzle (). In order to produce spherical metal particles () the droplets at the outlet of the nozzle () are fed to a coolant () for purposes of consolidation. The nozzle () dips into the coolant (), the temperature of the coolant () being below the melting point of the melt ().

Method and device for producing spherical metal particles

The invention provides a supported metal membrane which contains a metal membrane on a support surface of a porous membrane support. The supported metal membrane is obtainable by applying the metal membrane to the support surface of the membrane support, wherein the pores in the membrane support are sealed, at least in the region of the support surface, prior to applying the metal membrane and are opened by removing the auxiliary substance only after applying the metal membrane.

Supported metal membrane, a process for its preparation and use

A shaped, activated metal, fixed-bed catalyst with a pore volume of 0.05 to 1 ml/g and an outer activated layer consisting of a sintered, finely-divided, catalyst alloy and optionally promoters. The catalyst alloy has metallurgical phase domains, resulting from the method of preparation of the alloy, in which the largest phase by volume has a specific interface density of more than 0.5 &mgr;m,.

Shaped, activated metal, fixed-bed catalyst

Precision attachments containing a titanium-containing gold alloy which is covered with a gold film, capable of being cast on, which have a golden yellow color, are extremely corrosion-resistant and, despite base metal constituents, form no oxides at the place of casting-on.

Precision attachments for dental technology capable of being cast on

Gold-palladium alloys with a high gold content for dental applications should, for reasons of biocompatibility, not contain any toxically dubious components. For particularly corrosion-resistant and biocompatible Type 4 alloys, tin is needed as the only base-metal component in amounts between 0.7 and 5.8 wt % if one remains within defined limits in a palladium-tin diagram of FIG. 1, for Pt values less than 2%. Such alloys contain, in addition to gold and tin, 6 to 25 wt % palladium, 0 to 12 wt % platinum and 0 to 2 wt % of at least one of iridium, rhodium and/or ruthenium.

Gold-palladium alloys for dental materials

Palladium based dental alloys do not show unaesthetic discolorations after ceramic firing if said alloys contain 66-85% by weight palladium, 1-20% by weight gold; 0-4% by weight silver; 0-4% by weight of at least one of platinum, iron and/or cobalt; 0.5-7% by weight of each of gallium, tin and indium, whereby the amount of said components total 9-14% by weight; 0-2% by weight germanium and/or zinc; and 0-1% by weight iridium, ruthenium and/or rhenium.

Palladium based alloy for dental applications

Dustfree investment materials, for the production of accurately fitting cast parts, are described which contain water-soluble phosphates, magnesium oxide and silicon dioxide. The investment material is made up of two components (a) and (b) and component (a) contains the entire magnesium oxide, optionally a part of the silicon dioxide and, in the presence of silicon dioxide, 0.4 to 6% by weight of a hydrophile, organic solvent, and component (b) contains the phosphate, the remainder of the silicon dioxide and at least 0.5% by weight water.

Dustfree investment material for accurately fitting cast pieces and

White solder alloys for dental and jewelry parts, with working temperatures around 1000.degree. C., contain 38 to 70% by weight gold, 6 to 20% by weight palladium, 8 to 40% by weight silver, 1 to 6% by weight iron and/or cobalt, 0 to 10% by weight copper, 0-5% each by weight indium, zinc and tin, 0 to 4% each by weight gallium and germanium, ruthenium and/or rhenium. The sum of the contents of tin, zinc, indium, gallium and germanium can be between 1 and 5% by weight.

Solder alloy for dental and jewelry parts

A yellow dental alloy is disclosed with high gold content for castings and ceramic veneers with an adjusted thermal expansion coefficient that does not produce any undesirable discoloration of the ceramic veneers and that is very hard. It contains 70 to 85% by weight gold, 5 to 13% by weight silver, 2 to 9% by weight platinum, 0 to 4.5% by weight palladium, 0.05 to 1% by weight iridium, rhenium, rhodium and/or ruthenium, 2 to 8% by weight copper, 0.1 to 6% by weight indium, zinc and/or germanium, and 0 to 4% by weight gallium, iron and/or tungsten.

Yellow dental alloy with a high gold content

Growing community of inventors

Kleinwallstadt, Germany

Bernd Kempf