MULTIPLE BEAM ADDITIVE MANUFACTURING

• US 20170021455A1
• Filed: 06/10/2016
• Published: 01/26/2017
• Est. Priority Date: 06/10/2015
• Status: Abandoned Application

• Current Assignee: IPG Photonics Corporation
• Original Assignee: IPG Photonics Corporation
• Inventors: DALLAROSA, Joseph, O'NEILL, William, SPARKES, Martin, PAYNE, Andrew, SQUIRES, David
• Application Number:
  US15/179,661
• Publication Number:
  US 20170021455A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/36 of energy beam parameters
• CPC Class Codes: B22F 10/366 Scanning parameters, e.g. hatch distance or scanning strategy
• CPC Class Codes: B22F 12/41 characterised by the type, e.g. laser or electron beam
• CPC Class Codes: B22F 12/45 Two or more
• CPC Class Codes: B22F 12/47 parallel to the deposition plane
• CPC Class Codes: B22F 12/49 Scanners
• CPC Class Codes: B22F 12/52 Hoppers
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B23K 2103/08 Non-ferrous metals or alloys
• CPC Class Codes: B23K 26/0604 by a combination of beams
• CPC Class Codes: B23K 26/0626 Energy control of the laser beam B23K26/0622 takes precedence
• CPC Class Codes: B23K 26/073 Shaping the laser spot
• 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 26/0869 Devices involving movement of the laser head in at least one axial direction
• CPC Class Codes: B23K 26/342 Build-up welding
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 64/268 using laser beams; using electron beams [EB]
• CPC Class Codes: B29C 64/277 using multiple radiation means, e.g. micromirrors or multiple light-emitting diodes [LED]
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• 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

Systems and methods for multiple beam additive manufacturing use multiple beams of light (e.g., laser light) to expose layers of powder material in selected regions until the powder material fuses to form voxels, which form build layers of a three-dimensional structure. The light may be generated from selected light sources and coupled into an array of optical fibers having output ends arranged in an optical head in at least one line such that multiple beams are sequentially directed by the optical head to the same powder region providing multiple beam sequential exposures (e.g., with pre-heating, melting and controlled cool down) to fuse the powder region. The multiple sequential beams may be moved using various techniques (e.g., by moving the optical head) and according to various scan patterns such that a plurality of fused regions form each build layer.

Claims

1. A method for multiple beam additive manufacturing of a three-dimensional structure formed by a plurality of build layers, the method comprising:

providing an array of light sources and an array of optical fibers coupled to the array of light sources, respectively, and an optical head including output ends of the optical fibers, wherein the optical fiber output ends are arranged in at least one line;

delivering powder layers of powder material on a powder bed support system that moves vertically and incrementally to accommodate each of the powder layers; and

forming build layers of the three-dimensional structure in each of the powder layers of powder material by fusing powder regions to produce fused regions corresponding to voxels of the three-dimensional structure, wherein the fused regions of the powder material in each of the powder layers collectively form each of the respective build layers of the three-dimensional structure, wherein forming each of the build layers includes performing multiple beam sequential exposures with a varying intensity of light on a powder region to be fused in each powder layer, wherein performing each of the multiple beam sequential exposures includes generating light from light sources in the array of light sources and moving the line of the optical fiber output ends across the powder region such that beams of light are emitted from the optical fiber output ends and sequentially directed to the powder region to fuse the powder region.

2. The method for multiple beam additive manufacturing of claim 1 wherein the multiple beam sequential exposures with varying intensity of light are formed by at least one pre-heating beam emitted from at least one of the optical fiber output ends at a beginning of the line to provide pre-heating, at least one melting beam emitted from at least one of the optical fiber output ends at a middle of the line to provide melting, and at least one cool down beam emitted from at least one of the optical fiber output ends at an end of the line to provide controlled cool down.

3. The method for multiple beam additive manufacturing of claim 1 wherein the light sources include laser diodes.

4. The method for multiple beam additive manufacturing of claim 3 wherein the output power of the laser diodes ranges from 10 W to 60 W to provide the varying intensity of light.

5. The method for multiple beam additive manufacturing of claim 1 wherein the light sources include fiber lasers.

6. The method for multiple beam additive manufacturing of claim 1 wherein the output ends of the optical fibers are arranged in a one-dimensional array in the optical head.

7. The method for multiple beam additive manufacturing of claim 1 wherein the output ends of the optical fibers are arranged in a two-dimensional array in the optical head.

8. The method for multiple beam additive manufacturing of claim 1 wherein the output ends of the optical fibers are arranged in a two-dimensional staggered array in the optical head.

9. The method for multiple beam additive manufacturing of claim 1 wherein performing the multiple beam sequential exposures on each power region to be fused includes raster scanning the beams.

10. The method for multiple beam additive manufacturing of claim 1 wherein the powder material includes a metal powder.

11. The method for multiple beam additive manufacturing of claim 10 wherein the metal powder includes a Nickel-based superalloy powder.

12. The method for multiple beam additive manufacturing of claim 10 wherein the metal powder includes an austenite nickel-chromium-based superalloy powder.

13. The method for multiple beam additive manufacturing of claim 10 wherein the porosity of the three-dimensional structure is below 0.05 vol %.

14. The method for multiple beam additive manufacturing of claim 1 wherein the optical head is configured to produce beam spots having a size in a range of 10 to 500 μ

m and a spacing in a range of 0 to 600 μ

m.

15. A method for multiple beam additive manufacturing of a three-dimensional structure formed by a plurality of build layers, the method comprising:

delivering a powder layer of powder material to a powder bed support system;

forming a build layer of the three-dimensional structure in the powder layer of powder material by fusing powder regions to produce fused regions that collectively form the build layer, wherein forming the build layer includes performing multiple beam sequential exposures on powder regions to be fused in each powder layer, wherein performing each of the multiple beam sequential exposures includes sequentially directing beams of light with varying intensity to the powder region to fuse the powder region; and

repeating the delivering a powder layer and the forming a build layer in the powder layer to form each of the build layers of the three-dimensional structure and wherein each of the fused regions corresponds to a voxel of the three-dimensional structure.

16. The method for multiple beam additive manufacturing of claim 15 wherein performing each of the multiple beam sequential exposures includes generating light from laser diodes to provide the beams of light.

17. The method for multiple beam additive manufacturing of claim 15 wherein the beams of light form a one dimensional array of beam spots.

18. The method for multiple beam additive manufacturing of claim 15 wherein the beams of light form a two-dimensional array of beam spots.

19. The method for multiple beam additive manufacturing of claim 15 wherein the light beams produce beam spots having a size in a range of 10 to 500 μ

m and a spacing in a range of 0 to 600 μ

m.

20. A method for multiple beam additive manufacturing of a three-dimensional structure, the method comprising:

providing an array of light sources and an array of optical fibers coupled to the array of light sources, respectively, and an optical head including output ends of the optical fibers, wherein the optical fiber output ends are arranged in at least one line;

receiving build instructions for each build layer of the three-dimensional structure, the build instructions including at least optical head positioning data defining a position of the optical head and light source data identifying selected light sources and a power and exposure time for the selected light sources; and

forming each build layer of the three-dimensional structure by moving the optical head relative to powder layers of powder material in accordance with the optical head positioning data while activating selected light sources in accordance with the light source data to provide multiple beam sequential exposures with a varying intensity of light on a selected powder region in each of the powder layers to fuse the powder material in the selected powder region, wherein the fused regions of the powder material in each of the layers form the build layers of the three-dimensional structure.

21. The method for multiple beam additive manufacturing of claim 20 wherein the light source data includes data defining the power of the selected light sources to produce the varying intensity of light.

22. A multiple beam additive manufacturing system comprising:

a powder bed support system for supporting a powder bed and a three-dimensional structure formed therein and for moving the powder bed vertically and incrementally to accommodate multiple powder layers of powder material;

a powder delivery system for delivering each of the powder layers to form the powder bed;

an array of light sources for generating light;

an array of optical fibers coupled to the light sources, respectively;

a multiple beam optical head including output ends of the optical fibers; and

a control system for controlling the array of light sources, the powder bed support system, and the powder delivery system in coordination to form build layers of the three-dimensional structure in each of the powder layers delivered to the powder bed, the control system being configured to selectively control each of the light sources to generate light from selected light sources in the array of light sources and to move the line of the optical fiber output ends sequentially across a powder region to be fused to provide multiple beam sequential exposures with varying intensity on the powder region such that beams of light are emitted from the optical fiber output ends and sequentially directed to the powder region to fuse the powder region to provide fused regions that form voxels of the three-dimensional structure.

23. The multiple beam additive manufacturing system of claim 22 further comprising an optical head motion stage for moving the optical head relative to the powder layers on the powder bed support system to scan the beams of light across the powder layers.

24. The multiple beam additive manufacturing system of claim 22 wherein the output ends of the optical fibers are arranged in a one-dimensional array.

25. The multiple beam additive manufacturing system of claim 22 wherein the output ends of the optical fibers are arranged in a two-dimensional array.

26. The multiple beam additive manufacturing system of claim 22 wherein the control system is configured to control power and exposure time of selected light sources in the array of light sources.

27. The multiple beam additive manufacturing system of claim 22 wherein the control system is responsive to a build instruction file defining instructions to form each build layer of the three-dimensional structure from the powder layers.

28. The multiple beam additive manufacturing system of claim 27 wherein the build instruction file includes at least optical head positioning data defining a position of the optical head and light source data identifying the selected light sources and a power and exposure time for the selected light sources.

29. The multiple beam additive manufacturing system of claim 28 wherein the build instruction file further includes powder layer control data for controlling deposition of each powder layer.

30. The multiple beam additive manufacturing system of claim 22 wherein each of the light sources is a diode laser.