Patent · US Expired

Transparent aluminum oxynitride and method of manufacture

US4720362A · kind A · utility

287Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 20, 1985
Grant dateJan 19, 1988
Priority date
Expiry dateMar 20, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S501/904
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

An article of manufacture is provided comprising a polycrystalline cubic aluminum oxynitride having a density of at least 98% of theoretical density, and being transparent to electromagnetic radiation in the wavelength range from 0.3 to 5 micrometers with an in-line transmission of at least 20% in this range. A method of preparing the optically transparent aluminum oxynitride is also provided comprising the steps of forming a green body of substantially homogeneous aluminum oxynitride powder and pressureless sintering said green body in a nitrogen atmosphere and in the presence of predetermined additives which enhance the sintering process. Preferred additives are boron and yttrium in elemental or compound form.

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