Boron suboxide material and method for its preparation
US5135892A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 1991 |
| Grant date | Aug 4, 1992 |
| Priority date | — |
| Expiry date | Jul 12, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/96
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A superhard form of boron suboxide (B.sub.x O) comprises at least about 95% by weight of polycrystalline B.sub.6 O and has a KHN.sub.100 value of at least about 3800 kg/mm.sup.2. A method for forming the superhard boron suboxide comprises mixing stoichiometric amounts of boron oxide (B.sub.2 O.sub.3) powder and boron powder and subjecting the mixture to a temperature of about 1800.degree. C. to about 2200.degree. C. and a pressure of about 2,000 to about 6,000 psi while encapsulated by boron nitride. The boron powder comprises about 90 to 95% by weight of elemental boron (B), and at least about 1% by weight of a sintering aid, such as Mg.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.