Articles for use with highly reactive alloys

• US 20080156453A1
• Filed: 12/27/2006
• Published: 07/03/2008
• Est. Priority Date: 12/27/2006
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Gigliotti, Michael Francis Xavier, Bewlay, Bernard Patrick, Kelly, Thomas Joseph, Weimer, Michael James
• Granted Patent: US 7,790,101 B2
• Time in Patent Office: Days
• US Class Current: 164/412
• CPC Class Codes: C22B 34/1295 Refining, melting, remelting, working up of titanium
• CPC Class Codes: C22B 9/003 by induction
• CPC Class Codes: F27B 14/10 Crucibles
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

Articles for use with highly reactive alloys that include a graphite crucible having an interior, and at least a first protective layer applied to the interior of the graphite crucible in which the graphite crucible having the first protective layer is used for melting highly reactive alloys.

Claims

1. An article for use with highly reactive alloys comprising:

a graphite crucible having an interior; and

at least a first protective layer applied to the interior of the graphite crucible.

2. The article of claim 1 wherein the graphite crucible having the first protective layer is used for melting highly reactive alloys.

3. The article of claim 2 wherein the first protective layer comprises a foil liner.

4. The article of claim 2 wherein the first protective layer comprises a carbide coating.

5. The article of claim 3 wherein the foil liner is fabricated from a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum.

6. The article of claim 4 wherein the carbide coating is formed by applying a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum, to the interior of the crucible and heat treating the high melting point alloy element in a carborizing atmosphere.

7. The article of claim 3 wherein the foil liner comprises a thickness of from about 0.005 mm to about 2 mm.

8. The article of claim 5 wherein the foil liner is fabricated from the high melting point alloy element in the highly reactive alloy that has the highest melting point.

9. The article of claim 1 further comprising at least a second protective layer.

10. The article of claim 9 wherein the first protective layer comprises a foil liner and the second protective layer comprises a carbide coating.

11. The article of claim 9 wherein the first protective layer comprises a carbide coating and the second protective layer comprises a foil liner.

12. The article of claim 2 wherein the highly reactive alloy comprises an element selected from the group consisting of titanium, niobium, nickel, hafnium, iridium and rhenium.

13. An article for use with highly reactive alloys comprising:

a graphite crucible having an interior;

at least a first protective layer applied to the interior of the graphite crucible; and

at least a second protective layer applied to the first protective layer.

14. The article of claim 13 wherein the graphite crucible having the first protective layer and second protective layer is used for melting highly reactive alloys.

15. The article of claim 13 wherein the first protective layer comprises a foil liner and the second protective layer comprises a carbide coating.

16. The article of claim 13 wherein the first protective layer comprises a carbide coating and the second protective layer comprises a foil liner.

17. The article of claim 15 wherein the foil liner is fabricated from a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum, and wherein the carbide coating is formed by applying a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum, to the foil liner and heat treating the high melting point alloy element in a carborizing atmosphere.

18. The article of claim 16 wherein the carbide coating is formed by applying a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum, to the interior of the crucible and heat treating the high melting point alloy element in a carborizing atmosphere and wherein the foil liner is fabricated from a high melting point alloy element selected from the group consisting of niobium, tantalum, tungsten, and molybdenum.

19. The article of claim 14 wherein the highly reactive alloy comprises an element selected from the group consisting of titanium, niobium, nickel, hafnium, iridium and rhenium.

20. The article of claim 15 wherein the foil liner comprises a thickness of from about 0.005 mm to about 2 mm.