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:
Aug. 12, 2003
Filed:
Feb. 16, 2001
Ulrich Goetz, Buching, DE;
Rainer Hegermann, Rosshaupten, DE;
Sintec Keramik GmbH & Co. KG, Halblech, DE;
Abstract
The invention concerns a piston of finest grain carbon, having a bending strength of at least 100 MPa, a bending elongation >0.8%, an average interlayer distance c/2<0.35 nm, an average crystallite size in the c direction >5 nm and a heat conductivity of at least 10 W/mK, and a method for its production comprising: a) compacting of a polyaromatic mesophase powder to almost its final shape; b) heating of the green product at ambient pressure under a non-oxidizing atmosphere to a temperature of between 900 to 1300° C. and maintenance at this temperature; c) high-temperature treatment, thereby heating up to a temperature between 1400 and 2400° C. and holding this temperature for between 2 and 20 hours; d) cooling down of the shaped form to an ambient temperature at less than 4 K/min, and a polyaromatic mesophase powder for the production of such a piston, characterized by a) a portion of quinoline-insoluble components of ≧85 weight %; b) a portion of toluene-insoluble components of ≧90 weight %; wherein c) a shaped form produced from the powder after sintering up to 1000° C. has a mass residue of more than 90 weight % of the mass before sintering.