Patent · US Expired

Cutting tool blank

US3954930A · kind A · utility

4Cited by
2References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 9, 1970
Grant dateMay 4, 1976
Priority date
Expiry dateOct 9, 1990

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC04B35/111
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The present invention is directed to an improved cutting tool blank formed by hot pressing a mixture of finely divided high-purity alumina and from about 0.05% to 0.35% of magnesia. Up to 0.10% nickel oxide may be present. The hot pressing temperatures are effected at a temperature in the range of about 1300.degree.C to 1525.degree.C so that the crystal size of the alumina in the tool blank has an average size range from 1 to 2 microns and the pressed blank has a final product density in excess of 3.97 grams per cubic centimeter. The preferred density of the blank is in excess of 3.98 grams per cubic centimeter. The hot pressing is conducted under vacuum conditions.

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