Preparation of a dense, polycrystalline ceramic structure
AssigneeLos Alamos National Security, LLC
InventorsJason Cooley, Ching-Fong Chen, David Alexander
Life of this patent
Estimating the term…
Abstract
Ceramic nanopowder was sealed inside a metal container under a vacuum. The sealed evacuated container was forced through a severe deformation channel at an elevated temperature below the melting point of the ceramic nanopowder. The result was a dense nanocrystalline ceramic structure inside the metal container.
Claims7
A process for forming a dense, ceramic, polycrystalline structure from ceramic powder, comprising sealing ceramic powder inside a metal container under a vacuum, and then forcing the sealed, evacuated container through a severe deformation channel at an elevated temperature below the melting temperature of the ceramic powder, whereby a dense ceramic polycrystalline structure is formed inside the container.
The process of claim 4, wherein the dense, ceramic nanocrystalline structure formed inside the container is a dense, ceramic nanocrystalline phosphor.
An apparatus for forming dense, ceramic, crystalline structures from ceramic powder, comprising:
- a plurality of sealed, evacuated metal containers filled with ceramic powder;
- equal channel angular extrusion means for extruding said sealed, evacuated metal containers;
- conveyor belt means for receiving the sealed, evacuated metal containers filled with ceramic powder at one end of the conveyor belt means and sending them to the other end of the conveyor belt means;.
- means for heating, on the conveyor belt means, sealed, evacuated metal containers that are filled with ceramic powder;
- and
- robotic arm means for transporting a heated, sealed, evacuated metal container of ceramic powder from the conveyor belt means to the equal channel angular extrusion means for extrusion thereof.
A process for continuously forming dense, ceramic, polycrystalline structures from ceramic powder, comprising feeding ceramic powder inside a channel of an equal channel angular extrusion die, the ceramic powder blocked from flowing through the die by a movable spacer resting on a dense object inside the channel, the die heated at a temperature below the melting temperature of the ceramic powder in the die, and after a desired amount of powder has been fed into the die, compressing the powder inside the channel and then forcing the compressed powder through the die, whereby a dense, ceramic polycrystalline structure is formed.
Dependencies are inferred from the claim text.