Methods and apparatus for firing extruded metals
US5225155A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1991 |
| Grant date | Jul 6, 1993 |
| Priority date | — |
| Expiry date | Jul 22, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF27D7/06
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Methods and apparatus for protecting extruded metal powder green bodies (34) during firing are provided. In certain embodiments, one or more green bodies (34) are housed in a non-gas tight chamber (13) located in the hot zone (24) of a cold-wall vacuum/atmosphere furnace (10). Furnace gas, e.g., hydrogen, is supplied to the interior of the chamber (13). The resulting one-way flow out of the chamber (13) protects the green bodies (34) from the backflow of burn-out products, as well as from contaminants arising from the walls and internal components of the furnace (10). In other embodiments, green bodies (34) are housed in individual non-gas tight containers (36). The containers (36) minimize the amount of furnace gas which comes into contact with the green bodies (34) during sintering and thus minimize the level of exposure of the green bodies (34) to oxidative impurities in the furnace gas. When composed of the same material as the green bodies, the containers (36) also perform a getter function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.