System and method for controlling oxidation of metals during freeform casting

Patent metadata

Field	Value
Publication number	US-11020797-B2
Application number	US-201816141437-A
Country	US
Kind code	B2
Filing date	Sep 25, 2018
Priority date	Sep 25, 2018
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

A system is disclosed for printing a component. The system may have a nozzle controlled for movement within a plane. The nozzle may be configured to dispense a molten metal. A substrate may be positioned within a reservoir. The substrate may receive the molten metal to form the component in a printing operation. A heated barrier material in a molten state may be contained within the reservoir for forming a liquid barrier between an atmosphere and the substrate. The nozzle has a tip which is submerged within the liquid barrier while dispensing the molten metal during the printing operation. The liquid barrier forms a barrier between an atmosphere in a vicinity of the substrate and the substrate.

First claim

What is claimed is:

1. A method for printing a component, comprising:
using a reservoir to hold a barrier material heated to a flowable state to form a heated liquid barrier;
positioning a substrate within the reservoir and submerged in the heated liquid barrier;
positioning a nozzle at least partially within the liquid barrier such that a tip of the nozzle is submerged in the liquid barrier and disposed adjacent the substrate;
flowing a molten metal through the nozzle onto the substrate and moving the nozzle as necessary to form at least a portion of the component; and
using the heated liquid barrier to form a barrier which fully covers, encapsulates and insulates the substrate and molten metal from an ambient atmosphere in a vicinity of the substrate while the molten metal is being applied during a printing operation to prevent oxidation of the molten metal; and
wherein the molten metal is non-reactive with the heated barrier material, so that the molten metal forms the component without interference from, and exclusive of, the heated barrier material.

2. A system for printing a component, comprising:
a nozzle having a tip, the nozzle configured to dispense heated molten metal from the tip;
a reservoir;
a substrate positioned within the reservoir on which to receive the molten metal, the molten metal being used to form the component in a printing operation; and
a heated barrier material in a molten state contained within the reservoir for forming a liquid barrier between an atmosphere and the molten metal during the printing operation; and
the heated barrier material having a depth such that the tip of the nozzle is fully submerged within the liquid barrier while the nozzle is dispensing the molten metal during the printing operation, the liquid barrier forming a barrier which fully covers and encapsulates the molten metal, to thus form a barrier between an atmosphere in a vicinity of the substrate and the substrate during the printing operation, to prevent exposure of the molten metal to the atmosphere while the molten metal is being dispensed from the nozzle tip and applied to the substrate, and such that the molten metal is non-reactive with the heated barrier material, so that the molten metal forms the component without interference from, and exclusive of, the heated barrier material.

3. The system of claim 2 , wherein the heated barrier material is removable from a surface of the component formed on the substrate after completing the printing operation.

4. The system of claim 2 , wherein the heated barrier material comprises at least one of Cerium and Calcium, heated to a molten, flowable condition.

5. The system of claim 3 , wherein the heated barrier material is removable through at least one of a chemical etching operation or a chemical dissolution operation from a newly formed material layer after formation of the new material layer.

6. The system of claim 2 , wherein the molten metal comprises molten Aluminum.

7. The system of claim 6 , wherein the heated barrier material comprises one of:
Sodium;
Potassium;
eutectic KF—AlF3;
Bismuth;
Cadmium; and
Indium.

8. The system of claim 2 , wherein the molten metal used to perform the printing operation comprises Cerium.

9. The system of claim 2 , wherein the molten metal used to perform the printing operation comprises Uranium.

10. The system of claim 9 , wherein the heated barrier material comprises one of:
Calcium;
Magnesium;
Cerium;
Lanthanum;
Silver;
Europium;
Neodymium;
Samarium; and
eutectic KCl—LiCl.

11. The system of claim 2 , wherein the heated barrier material comprises a melting point lower than a melting point of a metal which is used to form the molten metal.

12. The system of claim 2 , wherein the heated barrier material comprises a boiling point higher than a printing temperature at which the molten metal is printed to the substrate.

13. The system of claim 2 , wherein the molten metal is substantially immiscible with the heated barrier material.

14. The system of claim 2 , wherein the heated barrier material is unreactive with the molten metal.

15. The system of claim 2 , further comprising an elevator component for raising the substrate out from the heated barrier material at the end of the printing operation.

16. The system of claim 2 , wherein the substrate comprises a heated substrate.

17. The system of claim 2 , further comprising a furnace in which the reservoir and the substrate are positioned during the printing operation.

18. A system for printing a component, comprising:
a controller;
a nozzle controlled for movement by the controller within a two dimensional plane, the nozzle having a tip configured to dispense a molten metal from the tip during a printing operation;
a reservoir;
a substrate positioned within the reservoir on which to receive the molten metal, the molten metal being used to form the component on the substrate in a layer-by-layer fashion; and
a heated barrier material in a molten state contained within the reservoir for forming a liquid barrier, and the nozzle tip configured to be fully submerged within the liquid barrier while dispensing the molten metal during the printing operation, the liquid barrier fully covering and encapsulating the molten metal as the molten metal is being deposited from the nozzle tip onto the substrate, and thus forming a barrier between an atmosphere in a vicinity of the substrate and the substrate; and
wherein the barrier material comprises a melting point below a melting point of a metal material used to form the molten metal, and wherein the barrier material and the molten metal are substantially immiscible, and wherein the molten metal is non-reactive with the heated barrier material, so that the molten metal forms the component without interference from, and exclusive of, the heated barrier material.

19. The system of claim 18 , wherein the substrate comprises a heated substrate.

Assignees

• L Livermore Nat Security Llc

Inventors

• Pascall Andrew J
• Kuntz Joshua David
• Mccall Scott K

Classifications

• B22D23/003 Primary

  Moulding by spraying metal on a surface · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B33Y40/00

  Auxiliary operations or equipment, e.g. for material handling · CPC title

• B22D45/00

  Equipment for casting, not otherwise provided for · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title