The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1987
Filed:
Apr. 21, 1986
Heinrich Knoch, Waltenhofen-Lanzen, DE;
Eckhart Bechler, Kempten, DE;
Alfred Lipp, Bad Worishofen, DE;
Elektroschmelzwerk Kempten GmbH, Kempten, DE;
Abstract
The invention is a polycrystalline sintered body based on lanthanum hexaboride and having a density of at least 95% of the theoretical density. The sintered body comprises lanthanum hexaboride, boron carbide and amorphous carbon, the content of B.sub.4 C+C being from 0.1 to 10% by weight and the total amount of La+B+C being at least 99.0% by weight, in each case calculated on the total weight. The sintered bodies have a homogeneous microstructure with mean grain sizes<10 .mu.m, in which, in addition to the crystalline lanthanum hexaboride phase, boron carbide and carbon are detectable as separate, finely divided phases. The sintered bodies can be manufactured by pressureless sintering at temperatures of from 2150.degree. to 2200.degree. C. from powder mixtures comprising lanthanum hexaboride and, in addition, mixtures of a carbon-containing material and a boron component.