Three-dimensional printing systems and methods of their use

• US 10,272,525 B1
• Filed: 12/27/2017
• Issued: 04/30/2019
• Est. Priority Date: 12/27/2017
• Status: Active Grant

• Current Assignee: Velo3D, Inc.
• Original Assignee: Velo3D, Inc.
• Inventors: Buller, Benyamin, Murphree, Zachary Ryan
• Primary Examiner(s): Evans, Geoffrey S
• Application Number:
  US15/855,744
• Time in Patent Office: 489 Days
• CPC Class Codes: B23K 2103/04 Steel or steel alloys
• CPC Class Codes: B23K 2103/05 Stainless steel
• CPC Class Codes: B23K 2103/10 Aluminium or alloys thereof
• CPC Class Codes: B23K 2103/14 Titanium or alloys thereof
• CPC Class Codes: B23K 2103/26 Alloys of Nickel and Cobalt and Chromium
• CPC Class Codes: B23K 26/0006 taking account of the properties of the material involved B23K26/32, B23K26/40 take precedence
• CPC Class Codes: B23K 26/082 Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head
• CPC Class Codes: B23K 26/0821 using multifaceted mirrors, e.g. polygonal mirror
• CPC Class Codes: B23K 26/0853 Devices involving movement of the workpiece in at least in two axial directions, e.g. in a plane
• CPC Class Codes: B23K 26/127 in an enclosure
• CPC Class Codes: B23K 26/142 for the removal of by-products
• CPC Class Codes: B23K 26/342 Build-up welding
• CPC Class Codes: B23K 26/707 for monitoring laser beam transmission optics
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

The present disclosure describes three-dimensional (3D) printing apparatuses and systems for producing 3D objects. Described herein are printing apparatuses and systems that are configured to facilitate control of debris within an enclosure where one or more printing operations are performed. Printing apparatuses and systems of the present disclosure may each have one or more components, such as, for example, component(s) that are configured to facilitate gas flow trajectories (e.g., turbulent movement) within an enclosure in which a 3D object is printed.

Claims

1. An apparatus for printing a three-dimensional object, the apparatus comprising:

a platform configured to support a powder bed comprising a powder material;

a layer forming device configured to form at least one layer of the powder material, wherein the layer forming device includes a blade or a roller configured to translate in a first direction over a surface of the powder bed to planarize the surface of the powder bed;

an elevator operationally coupled with the platform, wherein the elevator comprises a motor configured to translate the platform in a second direction substantially perpendicular to the first direction;

a processing chamber having one or more walls enclosing an internal volume, which one or more walls is configured to enclose the surface of the powder bed during printing, wherein the processing chamber includes a ceiling wall;

one or more lasers configured to generate one or more laser beams that (i) melts at least a portion of the powder bed to a molten material as part of the three-dimensional object during the printing, and (ii) forms gas-borne debris within the internal volume;

one or more windows coupled to the ceiling wall, wherein the one or more windows is configured to transmit the one or more laser beams to the internal volume;

one or more galvanometer scanners configured to move the one or more laser beams within a processing region of the internal volume of the processing chamber, wherein the one or more galvanometer scanners is external to the internal volume of the processing chamber;

a gas flow system comprising one or more openings disposed in the one or more walls, which gas flow system is operationally coupled with the processing chamber and configured to provide a flow of gas across at least a portion of the processing region, wherein during the printing the flow of gas maintains a debris concentration of about 1 milligrams per cubic meter to about 1,000 milligrams per cubic meter (a) in the processing region and (b) at least about 20 millimeters above the surface of the powder bed, wherein the printing results in the three-dimensional object having a porosity of about 1% or less by volume, wherein the gas flow system is configured to facilitate movement of the gas-borne debris at least in the processing region during the printing, wherein the gas flow system is configured to facilitate the movement of the gas-borne debris corresponding to a turbulent movement at least in the processing region; and

one or more controllers comprising electrical circuitry operationally coupled with the elevator, the layer forming device, the one or more galvanometer scanners, and the gas flow system, which one or more controllers are configured to direct (I) the elevator to translate the platform in the second direction, (II) the layer forming device to translate in the first direction, (III) the one or more galvanometer scanners to direct the one or more laser beams at the powder bed along at least one trajectory, and (IV) the gas flow system to provide the flow of gas.

2. The apparatus of claim 1, wherein the processing region has a shape that is configured to encompass (i) a motion range of the one or more laser beams that move along the at least one trajectory, and (ii) at least a portion of the surface of the powder bed.

3. The apparatus of claim 1, wherein the turbulent movement comprises a cyclic movement.

4. The apparatus of claim 1, wherein the turbulent movement comprises a backflow or a standing vortex.

5. The apparatus of claim 1, wherein at least one valve of the gas flow system is configured to facilitate the movement of the gas-borne debris.

6. The apparatus of claim 1, wherein an internal shape of the processing chamber is configured to facilitate the movement of the gas-borne debris.

7. The apparatus of claim 1, wherein at least one wall of the one or more walls is configured to facilitate the movement of the gas-borne debris.

8. The apparatus of claim 7, wherein the wall of the processing chamber is a side wall.

9. The apparatus of claim 1, wherein the flow of gas has a peak horizontal velocity height that varies along a length of the powder bed and/or the platform.

10. An apparatus for printing a three-dimensional object, the apparatus comprising:

a platform configured to support a powder bed comprising a powder material;

a layer forming device configured to form at least one layer of the powder material, wherein the layer forming device includes a blade or a roller configured to translate in a first direction over a surface of the powder bed to planarize the surface of the powder bed;

an elevator operationally coupled with the platform, wherein the elevator comprises a motor configured to translate the platform in a second direction substantially perpendicular to the first direction;

a processing chamber having one or more walls enclosing an internal volume, which one or more walls are configured to enclose the surface of the powder bed during the printing, wherein the processing chamber includes a ceiling wall;

one or more lasers configured to generate one or more laser beams that (i) melts at least a portion of the powder bed to a molten material as part of the three-dimensional object during the printing, and (ii) forms gas-borne debris within the internal volume;

one or more windows coupled to the ceiling wall, wherein the one or more windows is configured to transmit the one or more laser beams to the internal volume;

one or more galvanometer scanners configured to move the one or more laser beams within a processing region of the internal volume of the processing chamber, wherein the one or more galvanometer scanners is external to the internal volume of the processing chamber;

a gas flow system comprising one or more openings disposed in the one or more walls, which gas flow system is operationally coupled with the processing chamber and configured to provide a flow of gas across at least a portion of the processing region, wherein during the printing, the flow of gas maintains a debris concentration of 0.5 particles per cubic centimeter to 1,000 particles per cubic centimeter (a) in the processing region and (b) at least 20 millimeters above the surface of the powder bed, each of which particles has a diameter of 0.5 micrometer or greater, wherein the printing results in the three-dimensional object having a porosity of 1% or less by volume; and

one or more controllers comprising electrical circuitry operationally coupled with the elevator, the layer forming device, the one or more galvanometer scanners, and the gas flow system, which one or more controllers are configured to direct (I) the elevator to translate the platform in the second direction, (II) the layer forming device to translate in the first direction, (III) the one or more galvanometer scanners to direct the one or more laser beams at the powder bed along at least one trajectory, and (IV) the gas flow system to provide the flow of gas.

11. The apparatus of claim 10, wherein the debris concentration within the at least the portion of the processing region varies during the printing.

12. The apparatus of claim 10, wherein the gas-borne debris within the internal volume is formed during melting of the at least the portion of the powder bed to the molten material as part of the three-dimensional object.

13. The apparatus of claim 10, wherein the debris concentration is present at a height of at least 30 millimeters above the surface of the powder bed.

14. The apparatus of claim 10, wherein the debris concentration is present at a height of at least 50 millimeters above the surface of the powder bed.

15. The apparatus of claim 10, wherein the gas flow system is configured to provide at least a portion of the flow of gas in a direction that is substantially parallel to the surface of the powder bed and/or the platform.

16. The apparatus of claim 15, wherein the flow of gas has a peak horizontal velocity ranging from 0.2 meters per second to 2 meters per second (m/s).

17. The apparatus of claim 10, wherein the flow of gas has a peak horizontal velocity within a height of 15 millimeters and 100 millimeters (mm) above the surface of the powder bed and/or the platform.

18. The apparatus of claim 10, wherein each of the one or more lasers is configured to generate a laser beam having a power density ranging from 100 Kilo Watts per centimeter squared to 30,000 Kilo Watts per centimeter squared (KW/cm²), as measured at the surface of the powder bed.

19. The apparatus of claim 10, further comprising an optical system configured to modify at least one characteristic of the one or more laser beams, wherein the optical system is configured to generate a focused or a defocused laser beam at the surface of the powder bed.

20. An apparatus for printing a three-dimensional object, the apparatus comprising:

a platform configured to support a powder bed comprising a powder material;

a layer forming device configured to form at least one layer of the powder material as part of the powder bed, wherein the layer forming device includes a blade or a roller configured to translate in a first direction over a surface of the powder bed to planarize the surface of the powder bed;

an elevator operationally coupled with the platform, wherein the elevator comprises a motor configured to translate the platform in a second direction substantially perpendicular to the first direction;

a processing chamber having one or more walls enclosing an internal volume, which one or more walls is configured to enclose the surface of the powder bed during the printing, wherein the processing chamber includes a ceiling wall;

one or more lasers configured to generate one or more laser beams that (i) melts at least a portion of the powder bed to a molten material as part of the three-dimensional object during the printing, and (ii) forms gas-borne debris within the internal volume of the processing chamber;

one or more windows coupled to the ceiling wall, wherein the one or more windows is configured to transmit the one or more laser beams to the internal volume;

one or more galvanometer scanners configured to move the one or more laser beams in the internal volume of the processing chamber, wherein the one or more galvanometer scanners is external to the internal volume of the processing chamber;

a gas flow system comprising one or more openings disposed in the one or more walls, which gas flow system is operationally coupled with the processing chamber and configured to provide a flow of gas across each of the one or more laser beams, wherein during printing each of the one or more laser beams encounters at least 10 debris particles each having a diameter of 0.5 micrometers or greater, wherein the printing results in the three-dimensional object having a porosity of 1% or less by volume; and

one or more controllers comprising electrical circuitry operationally coupled with the elevator, the layer forming device, the one or more galvanometer scanners, and the gas flow system, which one or more controllers are configured to direct (I) the elevator to translate the platform in the second direction, (II) the layer forming device to translate in the first direction, (III) the one or more galvanometer scanners to direct the one or more laser beams at the powder bed along at least one trajectory, and (IV) the gas flow system to provide the flow of gas.

21. The apparatus of claim 20, wherein the debris particles encountered by the one or more laser beams are within a laser beam volume of each of the one or more laser beams.

22. The apparatus of claim 20, further comprising a build module removably coupled to the processing chamber during the printing, wherein the processing chamber is configured decouple from the build module after the printing.

23. The apparatus of claim 20, wherein during the printing, the gas flow system is configured to change a velocity of the flow of gas within the internal volume during.

24. The apparatus of claim 20, wherein the debris particles comprise at least 10% metal oxide measured as volume per volume.

25. The apparatus of claim 20, wherein during the printing, the apparatus is configured to melt at a rate from 1 to 50 cubic centimeters per hour (cm³/hr) of the molten material per laser.

26. The apparatus of claim 20, wherein the one or more openings is one or more inlet openings, wherein the flow of gas enters the internal volume through the one or more inlet openings and exits the internal volume through one or more outlet openings, which one or more inlet and outlet openings is configured to facilitate movement of the gas-borne debris.

27. The apparatus of claim 26, wherein the one or more inlet openings and/or the one or more outlet openings correspond to openings of a perforated plate, a screen, a mesh or a gas permeable material.

28. The apparatus of claim 26, wherein the one or more inlet openings are within an inlet region coupled to a ceiling of the processing chamber, and the one or more outlet openings are within a side wall or a floor of the processing chamber.

29. The apparatus of claim 26, wherein the one or more inlet openings are within an inlet region coupled to a first side wall of the processing chamber, and the one or more outlet openings are within a second side wall or a floor of the processing chamber.

30. The apparatus of claim 20, wherein during printing, each of the one or more laser beams encounters:

from 10 debris particles to 10,000 debris particles each having a size of 0.5 micrometers or greater.