Preparation of metal matrix composites under atmospheric pressure
US6106588A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1998 |
| Grant date | Aug 22, 2000 |
| Priority date | — |
| Expiry date | Mar 11, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22B9/103
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method and apparatus are provided for mixing nonmetallic reinforcing particles into a molten metal or metal alloy for the production of stir-cast metal matrix composite (MMC) materials under atmospheric or near-atmospheric pressure. In a preferred embodiment, the particles are introduced into the matrix under the surface of the matrix by feeding the particles through the inner passage of a rotatable hollow impeller tube positioned in the matrix. The impeller tube is terminated at its lower end by an impeller head. The impeller head includes one or more teeth and is positioned proximate to an impeller base. The particles enter the matrix through a shear region which exists in and around the volume between the impeller base and the impeller head. The rotating impeller and the high shear force thereby created wet the particles in the composite matrix and effect homogenization of the composite matrix. The particles are preferably fed into the matrix from a particle supply that is back-filled with an active gas like oxygen or a substantially inert gas. The process of the present invention may be practiced as a batch process or as a continuous process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.