Patent · US Expired

Method and system for producing carbon fibers

US5193996A · kind A · utility

14Cited by
8References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 12, 1991
Grant dateMar 16, 1993
Priority date
Expiry dateNov 12, 2011

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD01F9/32
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

High tensile carbon fibers are provided with a high yield process in which, after oxidation of a precursor, the fibers are first precarbonized in an inert atmosphere to to about 600.degree. C. while imparting 5-10% stretch. In precarbonizing, the fibers are intially heated in a sweeping manner with substantial volumes of hot inert gas which is extracted along with products of decomposition before the fibers are cooled to a low, non-reactive exit temperature. The arrangement minimizes redeposition of tars on the fibers and stretches the fibers in a range in which substantial off-gassing occurs. Thereafter the fibers are finally carbonized at a higher temperature with a different tension being applied, to provide a more reliable less sensitive process that enables oxidation to be effected more rapidly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.