Process for the powder-metallurgical production of a workpiece
US5174952A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 1990 |
| Grant date | Dec 29, 1992 |
| Priority date | — |
| Expiry date | Sep 6, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/77
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for the powder-metallurgical production of a workpiece by filling a binder-free and solvent-free, dry metal powder or ceramic powder into a mold, precompacting the powder by tapping and presintering it for 1/2 hour to 1 hour at 0.65 to 0.85 times the absolute melting temperature without significant shrinkage, adjacent powder particles being joined merely at their contact points by necking to give a skeletal formed body. The formed body is taken out of the mold and finish-sintered at at least 0.9 times the absolute melting temperature for at least 1 hour without additional support by a mold. Advantageously, the sintered body is additionally hot-isostatically pressed containerless in order to reach at least 98% of the theoretical density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.