Claims
- 1. A method of improving the strength of an alumina refractory material comprising exposing the alumina refractory material to a halogen gas by flowing the halogen gas into a furnace containing the refractory material in the presence of a reducing agent at a temperature between 1000° C. and 1400° C., wherein the exposure to the halogen gas reduces metallic impurities in the material.
- 2. The method of claim 1, wherein the halogen gas is selected from the group consisting of fluorine, iodine, and chlorine.
- 3. The method of claim 2, wherein the gas includes chlorine.
- 4. The method of claim 3, wherein the gas includes a mixture of chlorine and a carrier gas.
- 5. The method of claim 4, wherein the carrier gas includes helium.
- 6. The method of claim 1, wherein the exposing step takes place for at least one hour and less than 10 hours.
- 7. The method of claim 1, wherein the reducing agent is a carbon-containing material.
- 8. The method of claim 1, wherein the four point bend strength of the material is improved by at least 50% by the exposure to the halogen gas.
- 9. A furnace for the production of fused silica optical members including an alumina refractory material treated in accordance with the method of claim 1.
- 10. A method of improving the strength of an alumina refractory material comprising exposing the refractory material to chlorine gas at a temperature exceeding 1000° C. and for a time exceeding one hour, wherein the exposure improves the four point bend strength of the material by at least 50%.
- 11. The method of claim 10, wherein the step of exposing the refractory material to chlorine gas is performed in the presence of a carbon-containing material.
- 12. A furnace for the production of fused silica optical members including a refractory treated in accordance with claim 11.
- 13. A method of improving the strength of an alumina refractory material alumina refractory material comprising the step of exposing the alumina refractory material to a halogen gas, wherein the exposing step improves the four point bend strength of the material by at least 50%.
- 14. The method of claim 13, wherein the halogen gas includes chlorine.
- 15. The method of claim 13, wherein the exposing step takes place for at least one hour and less than 10 hours.
- 16. A furnace for the production of fused silica optical members including an alumina refractory material treated in accordance with the method of claim 13.
Parent Case Info
This is a Continuation of U.S. Ser. No. 10/016,838, filed Dec. 13, 2001, now abandoned, entitled Alumina Refractories and Methods Of Treatment, of Robert S. Pavlik, Jr.
US Referenced Citations (12)
Continuations (1)
|
Number |
Date |
Country |
Parent |
10/016838 |
Dec 2001 |
US |
Child |
10/438562 |
|
US |