Abstract: A material for use in making electrical contacts is produced in a powder form suitable for later processing into electrical contacts by standard metallurgical techniques generally involving compacting, sintering, and forming or cutting to make the desired contact size and shape. The material, and in most general applications the contact made from the material, essentially consists of silver, approximately 15% cadmium oxide by weight, and lithium oxide at a proportion of about .005 weight percent of lithium, which is approximately equal to .04 molecular percent of lithium oxide. The lithium oxide is added and uniformly distributed on the surfaces of the powder particles by precipitation.
Abstract: A matrix of a heat-resistant material with a filler of refractory oxides of metals contained in the matrix in the form of ground monocrystals.
Type:
Grant
Filed:
December 2, 1974
Date of Patent:
June 21, 1977
Inventors:
Vladimir Ilich Alexandrov, Vyacheslav Vasilievich Osiko, Ernest Nikolaevich Muraviev, Eduard Georgievich Spiridonov, Vladimir Mikhailovich Tatarintsev, Vladimir Grigorievich Gordon
Abstract: This application describes the addition of an alkali metal, generally in the form of a salt thereof, to a mixture of silver and cadmium oxide, prior to the sintering step, to improve the as-sintered densities of the resultant alloy material.
Abstract: A composition of material comprising aluminum oxide and refractory transition metal diborides, with additions of magnesium oxide and, optionally, transition metal carbides, nitrides, carbonitrides and iron group metals for sintering and grain morphology control, is disclosed, which is particularly useful as a cutting tool for steels, cast iron, and hard to machine materials, such as superalloys. In contrast to the TiC-Al.sub.2 O.sub.3 cermets of the prior art which have to be hot pressed for optimum properties, a large portion of the cermets of the invention can also be fabricated, without detriment to performance, by sintering the cold pressed powder compacts in an inert furnace atmosphere at temperatures between 1650.degree. and 1820.degree. C.