Method of producing metal strands and apparatus for producing metal strands

Patent metadata

Field	Value
Publication number	US-11980932-B2
Application number	US-202017609997-A
Country	US
Kind code	B2
Filing date	May 11, 2020
Priority date	May 10, 2019
Publication date	May 14, 2024
Grant date	May 14, 2024

Abstract

The invention relates to a method of producing elongate metal strands or fibres with a crucible, the method comprising the steps of; directing molten metal through a nozzle having a nozzle direction in a deposition direction at a regulated pressure difference between the inside and the outside of the crucible; depositing said molten metal from said nozzle on a rotating planar surface having an axis of rotation; entraining said molten metal in one plane via said rotating planar surface to form elongate metal strands, wherein said rotating surface is aligned at an alignment angle, to the deposition direction during the entraining of the molten metal; cooling said elongate metal strands to form solidified metal strands; and guiding said metal strands to collecting means to collect the solidified metal strands formed on the rotating planar surface.

First claim

The invention claimed is:

1. A method of producing at least one of elongate metal strands and fibres with a crucible, the method comprising the steps of:
directing molten metal through a nozzle opening of a nozzle having a nozzle direction in a deposition direction at a regulated pressure difference between the inside and the outside of the crucible, wherein the pressure difference is selected in the range from 50 mbar to 1 bar and wherein the pressure outside of the crucible is kept below atmospheric pressure;
depositing said molten metal from said nozzle on a rotating planar surface having an axis of rotation, wherein a spacing between the nozzle opening and the rotating planar surface is selected in a range of 10 μm to 20 mm, wherein the nozzle and the rotating planar surface are mounted within a chamber having an atmosphere at a pressure corresponding to a lower pressure than ambient pressure;
entraining said molten metal in one plane about said axis of rotation via said rotating planar surface to form the at least one of elongate metal strands and fibres, wherein said rotating planar surface is aligned at an alignment angle with regard to the deposition direction during the entraining of the molten metal;
cooling said elongate metal strands to form solidified metal strands; and
guiding said metal strands to collecting means to collect the solidified metal strands formed on the rotating planar surface.

2. The method according to claim 1 , wherein the rotating planar surface is arranged perpendicular to the deposition direction during said steps of entraining and cooling said molten metal, and wherein the rotating planar surface comprises a circular, oval, quadratic, rectangular or triangular shape.

3. The method according to claim 1 , wherein the alignment angle of the rotating planar surface is selected to lie in the range of 90° to 1° with respect to the deposition direction and/or the nozzle direction is selected to lie in the range of 0° to 90° with respect to the rotating planar surface.

4. The method according to claim 1 , wherein the rotating planar surface is a base interface of a rotating wheel.

5. The method according to claim 1 , wherein the axis of rotation is perpendicular to the rotating planar surface when the rotating planar surface is designed as a base interface of a rotating wheel.

6. The method according to claim 1 , wherein the deposition position of the nozzle relative to the rotating planar surface is adjusted, while an orientation of the nozzle is of any direction.

7. The method according to claim 1 , wherein the rotating planar surface is cooled.

8. An apparatus for producing elongate metal strands and fibres, the apparatus comprising:
a rotating planar surface mounted within a chamber having an atmosphere at a pressure corresponding to a lower pressure than ambient pressure,
at least one nozzle mounted within the chamber having an atmosphere at a pressure corresponding to a lower pressure than ambient pressure, the at least one nozzle having a nozzle direction and a nozzle opening for directing molten metal in a deposition direction at a regulated pressure difference between the inside and the outside of the nozzle, wherein the pressure difference is selected in the range from 50 mbar to 1 bar, and wherein the pressure outside of the nozzle is kept below atmospheric pressure, onto the rotating planar surface, wherein a spacing between the nozzle opening and the rotating planar surface is selected in a range of 10 μm to 20 mm, the rotating planar surface being configured to move under an alignment angle with respect to said deposition direction to entrain and cool the molten metal in one plane via said movement of the rotating planar surface to form solidified elongate metal strands at said rotating planar surface, and collecting means configured to collect the solidified strands of metal formed on the rotating planar surface and separated from the rotating planar surface by a force generated by the movement of the rotating planar surface.

9. The apparatus according to claim 8 , wherein the apparatus comprises a rotatable wheel.

10. The apparatus according to claim 8 , wherein the rotating planar surface is aligned perpendicular to the deposition direction during the entraining of the molten metal.

11. The apparatus according to claim 8 , wherein the rotating planar surface is aligned at an alignment angle with respect to the deposition direction during the entraining of the molten metal, wherein the alignment angle is selected to lie in the range of 90° to 1° and/or the nozzle direction is selected to lie in the range of 0° to 90° with respect to the rotating planar surface.

12. The apparatus according to claim 8 , wherein the rotating planar surface rotates around an axis of rotation, which is aligned perpendicular to the rotating planar surface.

13. The apparatus according to claim 8 , wherein a spacing between the nozzle opening and the rotating planar surface is at least 10 μm.

14. The apparatus according to claim 8 , wherein the rotating planar surface comprises at least one exchangeable plate.

15. The apparatus according to claim 14 , wherein a set of exchangeable plates is provided with each plate of the set of exchangeable plates being made from the same material as the remaining plates of the set of exchangeable plates, or wherein a variety of plates made from different materials is provided in the set of exchangeable plates.

16. The apparatus according to claim 8 , wherein a deposition position of the nozzle is adjustable at least parallel to the rotating planar surface.

17. The apparatus according to claim 8 , wherein the nozzle opening is of rectangular, circular, oval, quadratic or triangular geometry and is aligned in any direction with respect to the rotating planar surface.

18. The apparatus according to claim 8 comprising at least two nozzles, each nozzle having a nozzle opening for directing molten metal onto the rotating planar surface, wherein each nozzle is adjustable at least in parallel to the rotating planar surface.

19. The apparatus according to claim 18 that comprises between 4 and 12 nozzles.

20. The method according to claim 1 , wherein the pressure outside of the crucible is kept at 400 mbar.

21. The method according to claim 1 , wherein the spacing between the nozzle opening and the rotating planar surface is 50 μm, 100 μm, or 200 μm.

22. The method according to claim 1 , wherein the thickness of the manufactured metal strands is less than 25 μm, especially less than 10 μm.

23. The method according to claim 1 , wherein the manufactured metal strands comprise an aspect ratio of length to width from 2:1 up to 1000:1 or greater.

24. The method according to claim 1 , wherein a collector is arranged in a direction transverse to a circumference of the rotating planar surface to intercept the solidified metal strands.

25. The apparatus according to claim 8 , wherein the pressure outside of the crucible is kept at 400 mbar.

26. The apparatus according to claim 8 , wherein the spacing between the nozzle opening and the rotating planar surface is 50 μm, 100 μm, or 200 μm.

27. The apparatus according to claim 8 , wherein the thickness of the manufactured metal strands is less than 25 μm, especially less than 10 μm.

28. The apparatus according to claim 8 , wherein the manufactured metal strands comprise an aspect

Assignees

• Max Planck Gesellschaft

Inventors

• Spatz Joachim P

Classifications

• B22D13/101 Primary

  Moulds · CPC title

• B22D13/105 Primary

  Cooling for moulds or cores · CPC title

• B22D39/00

  Equipment for supplying molten metal in rations · CPC title

• B22F1/062

  Fibrous particles · CPC title

• B22F3/002

  Manufacture of articles essentially made from metallic fibres · CPC title