Accurate three-dimensional printing

• US 10,434,573 B2
• Filed: 02/16/2017
• Issued: 10/08/2019
• Est. Priority Date: 02/18/2016
• Status: Active Grant

• Current Assignee: Velo3D, Inc.
• Original Assignee: Velo3D, Inc.
• Inventors: Buller, Benyamin, Lappas, Tasso, Mendelsberg, Rueben Joseph, Milshtein, Erel, Korepanov, Sergey, Lappan, Alan Rick
• Primary Examiner(s): Sultana, Nahida
• Application Number:
  US15/435,078
• Publication Number:
  US 20170239892A1
• Time in Patent Office: 964 Days
• CPC Class Codes: B22F 10/12 by photopolymerisation, e.g. stereolithography [SLA] or digital light processing [DLP]
• CPC Class Codes: B22F 10/14 by jetting of binder onto a bed of metal powder
• CPC Class Codes: B22F 10/18 by mixing binder with metal in filament form, e.g. fused filament fabrication [FFF]
• CPC Class Codes: B22F 10/25 Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS]
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/32 of the atmosphere, e.g. composition or pressure in a building chamber
• CPC Class Codes: B22F 10/36 of energy beam parameters
• CPC Class Codes: B22F 10/47 characterised by structural features
• CPC Class Codes: B22F 10/80 Data acquisition or data processing
• CPC Class Codes: B22F 12/44 characterised by the configuration of the radiation means
• CPC Class Codes: B22F 12/49 Scanners
• CPC Class Codes: B22F 12/90 Means for process control, e.g. cameras or sensors
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B23K 15/0013 Positioning or observing workpieces, e.g. with respect to the impact; Aligning, aiming or focusing electronbeams
• CPC Class Codes: B23K 15/0086 welding for purposes other than joining, e.g. built-up welding
• CPC Class Codes: B23K 15/02 Control circuits therefor
• CPC Class Codes: B23K 26/032 using optical means
• CPC Class Codes: B23K 26/034 Observing the temperature of the workpiece
• CPC Class Codes: B23K 26/04 Automatically aligning, aiming or focusing the laser beam, e.g. using the back-scattered light
• CPC Class Codes: B23K 26/0643 comprising mirrors
• CPC Class Codes: B23K 26/342 : Build-up welding
• CPC Class Codes: B23K 26/702 : Auxiliary equipment
• CPC Class Codes: B28B 1/001 : Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material selective deposition modelling of metallic powder B22F10/00; rapid manufacturing of 3D objects in general and in particular of plastics B29C64/00
• CPC Class Codes: B28B 17/0081 : Process control
• 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 64/386 : Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B29C 64/393 : for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29C 64/40 : Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B29K 2105/251 : Particles, powder or granules expandable particles B29K2105/046
• 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 40/00 : Auxiliary operations or equipment, e.g. for material handling
• CPC Class Codes: B33Y 40/10 : Pre-treatment
• CPC Class Codes: B33Y 40/20 : Post-treatment, e.g. curing, coating or polishing
• CPC Class Codes: B33Y 50/02 : for controlling or regulating additive manufacturing processes
• CPC Class Codes: G05B 19/4099 : Surface or curve machining, making 3D objects, e.g. desktop manufacturing
• CPC Class Codes: G05B 2219/35134 : 3-D cad-cam
• CPC Class Codes: G05B 2219/49007 : Making, forming 3-D object, model, surface
• CPC Class Codes: Y02P 10/25 : Process efficiency

Abstract

The present disclosure provides three-dimensional (3D) printing methods, apparatuses, and systems using, inter alia, a controller that regulates formation of at least one 3D object (e.g., in real time during the 3D printing); and a non-transitory computer-readable medium facilitating the same. For example, a controller that regulates a deformation of at least a portion of the 3D object. The control may be in situ control. The control may be real-time control during the 3D printing process. For example, the control may be during a physical-attribute pulse. The present disclosure provides various methods, apparatuses, systems and software for estimating the fundamental length scale of a melt pool, and for various tools that increase the accuracy of the 3D printing.

Claims

1. A system for printing a three-dimensional object comprising:

an enclosure configured to enclose, at least during printing of the three-dimensional object, an atmosphere at a pressure that is an ambient atmospheric pressure or a positive pressure above the ambient atmospheric pressure;

an energy source that is configured to generate an energy beam that transforms a pre-transformed material to a transformed material as at least a portion of the three-dimensional object comprising a plurality of layers, which pre-transformed material is transformed over time to yield a plurality of physical attribute oscillations of a change in at least one physical attribute over time, wherein the transformed material comprises a plurality of melt pools that correspond to the plurality of physical attribute oscillations, wherein a layer of the plurality of layers comprises the plurality of melt pools;

a detector that is configured to detect the plurality of physical attribute oscillations; and

one or more controllers operatively coupled to the enclosure, the energy source and the detector, wherein the one or more controllers are configured to;

(i) at least during printing the three-dimensional object, direct maintaining an interior of the enclosure at the ambient atmospheric pressure or at a positive pressure;

(ii) direct the energy source to generate the energy beam that transforms the pre-transformed material to the transformed material as a first portion of the three-dimensional object, wherein transformation of the pre-transformed material over time generates the plurality of melt pools that yields the plurality of physical attribute oscillations;

(iii) evaluate, or direct evaluation of, an oscillation of the plurality of physical attribute oscillations detected by the detector to generate a result; and

(iv) use the result to alter at least one characteristic of the energy beam to form a melt pool as part of the three-dimensional object.

2. The system of claim 1, wherein the plurality of physical attribute oscillations comprises (I) a first temperature of the plurality of melt pools, (II) a second temperature adjacent to the plurality of melt pools, (III) a power of the energy source that generates the energy beam, (IV) a power density of the energy beam, or (V) any combination of (I), (II), (III) and (IV), wherein the detector is configured to detect a measurement of the physical attribute oscillations over time.

3. The system of claim 1, wherein the one or more controllers are configured to direct alteration of at least one characteristic of the energy beam at least in part by directing maintenance of substantially identical physical attribute oscillations within the plurality of physical attribute oscillations.

4. The system of claim 1, wherein the plurality of physical attribute oscillations comprises one or more wavelengths that are emitted from the first portion, wherein the detector is configured to detect a measurement of the physical attribute oscillations over time.

5. The system of claim 1, wherein the plurality of physical attribute oscillations comprises a wavelength of a radiation or an intensity of the radiation, which radiation is emitted (I) from a first area occupied by a footprint of the energy beam on the first portion, (II) from a second area adjacent to the first area occupied by a footprint of the energy beam on the first portion, or (III) from any combination of (I) and (II), wherein the detector is configured to detect a measurement of the physical attribute oscillations over time.

6. The system of claim 5, wherein the detector further corresponds to, or directs a correlation to a temperature value, which correlation is of (A) the intensity of the radiation, (B) the wavelength of the radiation, or (C) both the intensity and the wavelength of the radiation.

7. The system of claim 1, wherein the plurality of physical attribute oscillations comprises a wavelength, specularity, or an intensity of a radiation, which radiation is emitted from (I) from at least one melt pool of the plurality of the melt pools, (II) from an area adjacent to the at least one melt pool, or (III) a combination of (I) and (II), wherein the detector is configured to detect a measurement of the physical attribute oscillations over time.

8. The system of claim 1, further comprising a layer dispensing mechanism that includes a cyclonic separator, which layer dispensing mechanism is configured to planarize a material bed that comprises the pre-transformed material.

9. The system of claim 1, wherein the one or more controllers are configured to direct the energy source to generate the energy beam that generates a melt pool of the plurality of melt pools thus generating the plurality of physical attribute oscillations.

10. The system of claim 1, wherein the one or more controllers are configured to direct the energy source to generate the energy beam that transforms the pre-transformed material to the transformed material thus yielding an oscillation having an asymmetric intensity profile over time, wherein the plurality of physical attribute oscillations comprises the oscillation.

11. The system of claim 1, wherein the one or more controllers are configured to direct the energy source to generate the energy beam to transform the pre-transformed material to a transformed material in a stepwise sequence to form the plurality of melt pools.

12. A method for printing a three-dimensional object comprising:

(a) providing a system comprising;

an enclosure configured to enclose, at least during printing of the three-dimensional object, an atmosphere at a pressure that is an ambient atmospheric pressure or a positive pressure above the ambient atmospheric pressure;

an energy source that is configured to generate an energy beam that transforms a pre-transformed material to a transformed material as at least a portion of the three-dimensional object comprising a plurality of layers, which pre-transformed material is transformed over time to yield a plurality of physical attribute oscillations of a change in at least one physical attribute over time, wherein the transformed material comprises a plurality of melt pools that correspond to the plurality of physical attribute oscillations, wherein a layer of the plurality of layers comprises the plurality of melt pools;

a detector that is configured to detect the plurality of physical attribute oscillations; and

one or more controllers operatively coupled to the enclosure, the energy source and the detector, wherein the one or more controllers are configured to;

(i) at least during printing the three-dimensional object, direct maintaining an interior of the enclosure at the ambient atmospheric pressure or at a positive pressure;

(ii) direct the energy source to generate the energy beam that transforms the pre-transformed material to the transformed material as a first portion of the three-dimensional object, wherein transformation of the pre-transformed material over time generates the plurality of melt pools that yields the plurality of physical attribute oscillations;

(iii) evaluate, or direct evaluation of, an oscillation of the plurality of physical attribute oscillations detected by the detector to generate a result; and

(iv) use the result to alter at least one characteristic of the energy beam to form a melt pool as part of the three-dimensional object; and

(b) using the system to print the three-dimensional object.

13. The method of claim 12, wherein a physical attribute oscillation of the plurality of physical attribute oscillations correlate to a first temperature of at least one melt pool of the plurality of melt pools, a second temperature adjacent to the at least one melt pool, a power of the energy source that generates the energy beam, a power density of the energy beam, a specularity of electromagnetic radiation, a reflectivity of electromagnetic radiation, or any combination thereof;

and wherein a measurement of the plurality of physical attribute oscillations is performed using correlation to the plurality of physical attribute oscillations detected by the detector over time.

14. The method of claim 13, wherein adjacent to the at least one melt pool is at a distance of at most about six melt pool diameters from a melt pool circumference.

15. The method of claim 12, wherein individual melt pools of the plurality of melt pools have a substantially identical fundamental length scale.

16. The method of claim 12, wherein a physical attribute oscillation of the plurality of the physical attribute oscillations comprises a dwell time of the energy beam in which it transforms the pre-transformed material to the transformed material and an intermission in transformation of the pre-transformed material to the transformed material.

17. The method of claim 16, wherein using the one or more controllers to evaluate, or to direct evaluation of, the oscillation comprises using the one or more controllers to perform, or to direct performance of, a calculation during printing of the three-dimensional object.

18. The method of claim 16, wherein using the one or more controllers to evaluate, or to direct evaluation of, the oscillation comprises using the one or more controllers to perform, or to direct performance of, a calculation during the intermission.

19. The method of claim 16, further comprising controlling at least a portion of the plurality of physical attribute oscillations to maintain over time a substantially identical (1) leading-edge, (2) tailing edge, (3) plateau, or (4) any combination of the leading-edge, the tailing edge and the plateau.

20. The method of claims 19, further comprising maintaining over time a substantially identical intensity, time span, or intensity and time span of (1) the leading-edge, (2) the tailing edge, (3) the plateau, or (4) any combination of the leading-edge, the tailing edge and the plateau.

21. The method of claim 12, wherein use the result to alter at least one characteristic of the energy beam comprises using closed loop control having a loop sample time of at most about 20 milliseconds.

22. The method of claim 12, further comprising maintaining a substantially identical profile of the plurality of physical attribute oscillations over time by controlling at least a portion of the plurality of physical attribute oscillations.

23. The method of claim 22, wherein the substantially identical profile comprises (1) a first temperature profile of the plurality of melt pools, (2) a second temperature profile of a position adjacent to the plurality of melt pools, (3) a power density profile of the energy beam, or (4) a power profile of the energy source generating the energy beam.

24. The method of claim 12, further comprising using the detector to detect the plurality of physical attribute oscillations by detecting one or more wavelengths emitted from a portion of the transformed material;

and wherein a measurement of the plurality of physical attribute oscillations is performed using at least the one or more wavelengths detected by the detector over time.

25. The method of claim 12, further comprising using the detector to detect the plurality of physical attribute oscillations by detecting one or more wavelengths emitted from (i) the plurality of melt pools, (ii) an area adjacent to the plurality of melt pools, or (iii) any combination of (i) and (ii);

and wherein a measurement of the plurality of physical attribute oscillations is performed using at least the one or more wavelengths detected by the detector over time.

26. The method of claim 12, wherein the pre-transformed material is at least a portion of a material bed, and wherein the material bed is planarized during printing of the three-dimensional object using a layer dispensing mechanism comprising a cyclonic separator.

27. The method of claim 12, further comprising using the detector to detect a radiation characteristic comprising a wavelength, a specularity, or an intensity of the radiation, which radiation is emitted from (1) a footprint of the energy beam on the portion of the transformed material, (2) an area adjacent to the footprint of the energy beam on the portion of the transformed material, or (3) any combination of (1) and (2);

and wherein a measurement of the plurality of physical attribute oscillations is performed using at least the radiation characteristic detected by the detector over time.

28. The method of claim 27, further comprising correlating, to a temperature value, the (i) intensity of the radiation, (ii) wavelength of the radiation, or (iii) any combination of (i) and (ii).