Method and apparatus for production of a cast component

• US 7,779,890 B2
• Filed: 08/20/2007
• Issued: 08/24/2010
• Est. Priority Date: 11/20/1998
• Status: Expired due to Fees

• Current Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Inventors: Vessely, Patrick A., Schlienger, M. Eric, Frasier, Donald J.
• Primary Examiner(s): Kerns; Kevin P
• Application Number:
  US11/894,221
• Publication Number:
  US 20080169081A1
• Time in Patent Office: 1,100 Days
• Field of Search: 164/65, 164/66.1, 164/120, 164/122, 164/136, 164/258, 164/335
• US Class Current: 164/335
• CPC Class Codes: B22D 47/00 Casting plants
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: C30B 11/00 Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method C30B13/00, C30B15/00, C30B17/00, C30B19/00 take precedence; under a protective fluid C30B27/00
• CPC Class Codes: C30B 11/002 Crucibles or containers for supporting the melt
• CPC Class Codes: C30B 11/14 characterised by the seed, e.g. its crystallographic orientation
• CPC Class Codes: C30B 29/52 Alloys
• CPC Class Codes: G03F 7/0037 Production of three-dimensional images
• CPC Class Codes: G03F 7/0047 characterised by additives for obtaining a metallic or ceramic pattern, e.g. by firing
• CPC Class Codes: Y10S 117/90 Apparatus characterized by composition or treatment thereof, e.g. surface finish, surface coating
• CPC Class Codes: Y10T 117/10 Apparatus
• CPC Class Codes: Y10T 117/1016 with means for treating single-crystal [e.g., heat treating]

Abstract

A system for producing cast components from molten metal. One form of the present invention includes a system for the precision pouring of molten metal within a casting mold. The precision pouring system is driven by a pressure differential.

Claims

1. A system, comprising:

a vacuum furnace;

a crucible positioned within said vacuum furnace and having a discharge hole;

a heater positioned within said vacuum furnace for melting the metal material within said crucible;

a metallic starter seed;

a dispenser located within said crucible and around said discharge hole, said dispenser has an outer portion with at least one entrance for the passage of molten metal from said crucible and an exit spaced from said at least one entrance for the passage of molten metal to an inner reservoir, and wherein said inner reservoir receives molten metal from said outer portion until said inner reservoir reaches a full state, and at said full state the flow of molten metal to said inner reservoir is stopped and the molten metal within said inner reservoir is discharged through said discharge hole;

an integral free form fabricated ceramic shell having a first opening for receiving the molten metal discharged through said discharge hole and a second opening for receiving said starter seed, said ceramic shell positioned within and connected with a mold container; and

a heat transfer pathway mechanically connected with said starter seed for the removal of heat from said starter seed, said heat transfer pathway remains mechanically connected with said starter seed as the molten metal within said ceramic shell is directionally solidified.

2. The system of claim 1, which further includes a heater operatively coupled with said starter seed to selectively heat said starter seed.

3. The system of claim 1, wherein said ceramic shell has a thin outer wall, and which further includes a plurality of supporting members within said mold container and abutting said thin outer wall, wherein said plurality of supporting members reinforcing said ceramic shell.

4. The system of claim 3, wherein said ceramic shell and mold container define a casting mold capable of withstanding casting pressures up to about twenty-four inches of nickel.

5. The system of claim 1, which further includes a nozzle coupled to said crucible and in fluid communication with said discharge hole, and wherein said nozzle is positionable in close proximity with said first opening of the ceramic shell.

6. The system of claim 5, wherein said nozzle and said ceramic shell define a structure having a substantially closed passageway therebetween during the passage of molten metal from said dispenser to said ceramic shell.

7. The system of claim 1, wherein the discharge of molten metal from said discharge hole is controlled by a pressure differential.

8. The system of claim 1, wherein said heat transfer passageway includes at least one member that mechanically grips said starter seed, said at least one member is conductively connected with said starter seed.

9. The system of claim 8, wherein said at least one member defines a pair of members that mechanically grip said starter seed.

10. The system of claim 1 wherein said starter seed has a surface adapted for receiving molten metal thereon, and which further includes a means for locating said surface at a predetermined location within said ceramic shell.

11. The system of claim 1:

wherein said ceramic shell and said mold container define a casting mold, said ceramic shell has a thin outer wall, and which further includes a plurality of ceramic members positioned within said mold container and abutting an outer surface of said thin outer wall, and wherein said plurality of supporting members mechanically reinforce said ceramic shell;

which further includes a nozzle coupled to said crucible and disposed in fluid communication with said discharge hole, and wherein said nozzle is positionable in close proximity with said first opening of the ceramic shell; and

wherein the discharge of molten metal from said discharge hole is controlled by a pressure differential;

wherein said heat transfer pathway is formed in a pair of conductive members that mechanically grip said starter seed; and

wherein said starter seed has a surface adapted for receiving molten metal thereon, and which further includes at least one locating member contacting said starter seed to position said surface at a predetermined location within said ceramic shell.

12. The system of claim 11, wherein said ceramic shell is formed in a process including the photopolymerization of a ceramic filled resin.

13. The system of claim 1, wherein said ceramic shell is formed by a stereolithography process.

14. A system comprising:

a vacuum furnace;

a crucible positioned within said vacuum furnace and having a discharge hole;

a heater positioned within said vacuum furnace for melting the metal material within said crucible;

a metallic starter seed;

a dispenser located within said crucible and around said discharge hole, said dispenser has an outer portion with at least one entrance for the passage of molten metal from said crucible and an exit spaced from said at least one entrance for the passage of molten metal to an inner reservoir, and wherein said inner reservoir receives molten metal from said outer portion until said inner reservoir reaches a full state, and at said full state the flow of molten metal to said inner reservoir is stopped and the molten metal within said inner reservoir is discharged through said discharge hole;

an integral free form fabricated ceramic shell having a first opening for receiving the molten metal discharged through said discharge hole and a second opening for receiving said starter seed; and

a heat transfer pathway mechanically connected with said starter seed for the removal of heat from said starter seed, said heat transfer pathway remains mechanically connected with said starter seed as the molten metal within said ceramic shell is directionally solidified.

15. The system of claim 14, which further includes a heater operatively coupled with said starter seed to selectively heat said starter seed.

16. The system of claim 14, wherein said ceramic shell has a thin outer wall.

17. The system of claim 14, which further includes a nozzle coupled to said crucible and in fluid communication with said discharge hole, and wherein said nozzle is positionable in close proximity with said first opening of the ceramic shell.

18. The system of claim 17, wherein said nozzle and said ceramic shell define a structure having a substantially closed passageway therebetween during the passage of molten metal from said dispenser to said ceramic shell.

19. The system of claim 14, wherein the discharge of molten metal from said discharge hole is controlled by a pressure differential.

20. The system of claim 14, wherein said heat transfer passageway includes at least one member that mechanically grips said starter seed, said at least one member is conductively connected with said starter seed.

21. The system of claim 20, wherein said at least one member defines a pair of members that mechanically grip said starter seed.

22. The system of claim 14, wherein said starter seed has a surface adapted for receiving molten metal thereon, and which further includes a means for locating said surface at a predetermined location within said ceramic shell.

23. The system of claim 14:

wherein said ceramic shell has a thin outer wall;

which further includes a nozzle coupled to said crucible and disposed in fluid communication with said discharge hole, and wherein said nozzle is positionable in close proximity with said first opening of the ceramic shell;

wherein the discharge of molten metal from said discharge hole is controlled by a pressure differential;

wherein said heat transfer pathway is formed in a pair of conductive members that mechanically grip said starter seed; and

wherein said starter seed has a surface adapted for receiving molten metal thereon, and which further includes at least one locating member contacting said starter seed to position said surface at a predetermined location within said ceramic shell.