Patent · US Expired

Method of forming a silicon nitride article

US4125592A · kind A · utility

7Cited by
1References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 9, 1977
Grant dateNov 14, 1978
Priority date
Expiry dateDec 9, 1997

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC04B35/591
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method for forming a silicon nitride article is set forth. An article having silicon particles therein is formed in a manner which provides a degree of porosity for the article. The silicon particles of the article are reactable with nitrogen to form silicon nitride. The article is heated to a temperature below a significant reaction temperature at which nitrogen gas reacts with the silicon particles at a measurable rate. The article is surrounded with an atmosphere containing nitrogen gas. A reaction zone is established on at least a portion of the surface area of the article. The reaction zone has a temperature above the significant reaction temperature whereby the silicon particles in the reaction zone are reacted at a measurable rate with the nitrogen gas to form silicon nitride. The reaction zone is moved in a controlled manner from the surface of the article into the interior of the article whereby the article is progressively nitrided inwardly into its bulk from the surface thereof.

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