Schwarzkopf Technologies Corporation

Siemens Aktiengesellschaft

Wolfgang Kock

Gunter Kneringer

Joachim Resch

Horst Greiner

Ralf Eck

Johann Eiter

The manufacture of powdered feed materials for hard fine grained metal body production includes the reduction of metal oxides into powdered metal and the subsequent carburization into metal carbide. Processes currently used are very cost intensive, mainly because of very long reaction times at high temperatures. According to applicant's economical process, the above reactions occur in the range of seconds and in a high-temperature cyclone as the reaction chamber. The apparatus is rather simple to construct. The stock to undergo reaction is continuously introduced into the chamber as a solid powdered phase with reaction gas and/or carrier gas, and passes through the chamber on predetermined paths for reaction, without leaving the solid state thereby.

Process for manufacture of powder compact feed materials for fine

Method for the reduction of metallic compounds

The invention relates to a hard solder for high-temperature soldered joints joining high temperature-resistant materials, especially chromium and alloys based on chromium. The hard solder consists of 40% to 70% by weight chromium, up to 2% by weight of one or several of the metals selected from the group of vanadium, niobium, tantalum, titanium, zirconium and hafnium, up to 2% by weight of one or several of the metals or their oxides selected from the group of rare earths and yttrium, as well as nickel as the balance. The solder according to the present invention is particularly suitable for joining by soldering parts in solid-electrolyte, high-temperature fuel cells.

Hard solder

A material for metal components, such as bipolar plates and window foils of high-temperature fuel cell systems, has ceramic solid electrolytes made of yttrium-stabilized zirconium oxide. The material includes a chromium alloy having from 3 to 10 atom % iron and from 0.5 to 5 atom % of rare earth metal and/or rare earth metal oxide, having a coefficient of thermal expansion at a temperature of 200.degree. C. amounting to from 8.5.times.10.sup.-6 to 10.5.times.10.sup.-6 per kelvin by which the temperature rises, and attaining a value at 900.degree. C. in a range from 14.times.10.sup.-6 to 15.times.10.sup.-6.

Material for the metal components of high-temperature fuel cell systems

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Reutte, Austria

Wolfgang Kock