Patent · US Expired

Preparation and sintering of refractory metal borides, carbides and nitrides of high purity

US4693989A · kind A · utility

14Cited by
13References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 29, 1985
Grant dateSep 15, 1987
Priority date
Expiry dateMay 29, 2005

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22C1/058
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The invention relates to the production of desirably consolidated high purity refractory metal borides, carbides, nitrides, or mixtures, combinations of cermets thereof. In the preparation, a second stage reaction is conducted at reduced pressure and sintering temperature. Furthermore, it is carried out in the presence of sintering aid which can be initially present as a particulate material and, as such, may be incorporated with other reaction ingredients. Sintering aid, in a dual role, may serve not only as an assistant in the second stage reaction, but also as a reaction participant. Moreover, during such rection at sintering conditions, the sintering assistance is obtained by means of sintering aid vapor. High purity products of desirable microstructure can be achieved, having densities on the order of 90 percent or more.

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