Patent · US Expired

Firing process for alumina yarn

US3953561A · kind A · utility

10Cited by
8References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 19, 1975
Grant dateApr 27, 1976
Priority date
Expiry dateFeb 19, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/19
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Process for producing continuous alumina multifilament yarns which comprises preparing an aqueous spinning mix containing selected alumina particles and water-soluble precursors of alumina in selected amounts, spinning filaments from the mix, forming a continuous filament package on a collapsible, refractory bobbin at a windup speed which attenuates the filaments, firing the package in a furnace at selected temperatures in either one or two steps, and then firing the yarn while backwinding it. A bobbin is obtained which is wound with strong substantially straight yarn of at least five aligned polycrystalline .alpha.-alumina continuous filaments, which yarn can be backwound from the bobbin.

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