Method of casting an article
US4862947A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 1988 |
| Grant date | Sep 5, 1989 |
| Priority date | — |
| Expiry date | Aug 2, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B11/002
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An improved mold has a coating of material having a relatively high emissivity. The surface of the coating has an emissivity which is at least twice as great as the emissivity of the surface of the ceramic mold material. When the mold is removed from a furnace chamber, the surface of the coating radiates heat at a relatively high rate. In one embodiment of the invention, the coating is applied to only a portion of the surface of a ceramic mold. In another embodiment of the invention, the coating of material having a relatively high emissivity is applied to only a portion of a crystal selector on a mold for a single crystal article. The relatively high rate of radiation of heat from the coated portion of the crystal selector increases the rate of growth of an adjacent single crystal grain. If desired, the entire mold can be covered with the coating of material having a relatively high emissivity. The coating of material having a high emissivity may be formed of graphite.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.