Production of metal and metalloid nitrides
US5466310A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1993 |
| Grant date | Nov 14, 1995 |
| Priority date | — |
| Expiry date | Aug 18, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C1/055
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A nitride of a metal or solid metalloid is produced by ball milling a powder of a metal or metalloid in a nitrogen, or nitrogen-containing atmosphere (such as ammonia). The pressure in the ball mill is normally from 100 to 5,000 kPa, typically about 300 kPa. The ball mill temperature may be from room temperature to 500.degree. C., preferably from 200.degree. C. to 400.degree. C. The product powder is normally pressure moulded and annealed at 800.degree. C. for about 1 hour to produce a strong, hard body. Controlling the degree of nitration, or mixing the product nitride powder with a metal powder before pressure moulding, enables a composite comprising a metal matrix with a dispersed nitride phase to be produced. An alternative technique, involves ball milling the metal or metalloid powder with an organic nitrogen-containing chemical which dissociates in the ball mill. This yields a mixture of the nitride and carbide of a metal or solid metalloid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.