Sinterable separation material in additive manufacturing

Patent metadata

Field	Value
Publication number	US-10800108-B2
Application number	US-201916419776-A
Country	US
Kind code	B2
Filing date	May 22, 2019
Priority date	Dec 2, 2016
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

According to one aspect, embodiments of the invention provide a method of 3D printing, comprising depositing a model material in successive layers to form a part, the model material being a metal composite including greater than 50% by volume metal powder and less than 50% by volume a first removable binder, depositing the model material in successive layers to form a support structure adjacent the part, depositing a sinterable separation material between a surface of the part and a surface of the support structure, the sinterable separation material formed from 10-40% by volume ceramic powder and greater than 50% by volume a second removable binder, debinding the first removable binder of the model material and the second removable binder of the sinterable separation material, and sintering the part, the support structure, and the sinterable separation material at a temperature profile that sinters the model material and the sinterable separation material.

First claim

What is claimed is:

1. A method of 3D printing, comprising:
depositing a model material in successive layers to form a part, the model material being a metal composite including greater than 50% by volume metal powder and less than 50% by volume first removable binder;
depositing the model material in successive layers to form a support structure adjacent the part;
depositing a sinterable separation material between a surface of the part and a surface of the support structure, the sinterable separation material formed from 10-40% by volume ceramic powder and greater than 50% by volume second removable binder;
debinding the first removable binder of the model material and the second removable binder of the sinterable separation material; and
sintering the part, the support structure, and the sinterable separation material at a temperature profile that sinters the model material and the sinterable separation material.

2. The method according to claim 1 , wherein the first removable binder and the second removable binder share more than 80% of their ingredients by volume.

3. The method according to claim 1 , further comprising:
depositing on a build plate the model material in successive layers to form a shrinking platform on which the part and the support structure are formed; and depositing a sliding release layer below the shrinking platform, the sliding release layer configured to remain powdered at a sintering temperature of the model material and to promote sliding between the shrinking platform and the build plate during the sintering.

4. The method according to claim 1 , wherein sintering the sinterable separation material includes sintering the sinterable separation material such that the sinterable separation material becomes at least one of fragmented, cracked, flaked, and breakable after the sintering.

5. The method according to claim 4 , further comprising removing the sintered separation material.

6. The method according to claim 5 , wherein removing the sintered separation material includes applying mechanical energy to the sintered separation material and separating the sintered separation material from the part.

7. The method according to claim 1 , further comprising forming physical connections between the part and the support structure, the physical connections configured to remain in place throughout the sintering and to be separated from the part after the sintering by applying mechanical energy.

8. The method according to claim 7 , wherein the physical connections between the part and the support structure are formed from the model material.

9. The method according to claim 7 , wherein the physical connections between the part and the support structure are formed from the sinterable separation material.

10. The method according to claim 1 , wherein depositing the sinterable separation material includes depositing the sinterable separation material with a first nozzle having a lateral translation speed that is 10-75% of a lateral translation speed of a second nozzle through which the model material is deposited.

11. The method according to claim 1 , further comprising depositing the sinterable separation material in a wiping process in which a path of deposition is retraced.

12. The method according to claim 1 , further comprising purging the sinterable separation material from a nozzle after a predefined amount of the sinterable separation material has been deposited.

13. The method according to claim 1 , wherein depositing the model material within any one of the successive layers includes depositing more than 50% of a total amount of the model material to be deposited within the layer before depositing more than 50% of a total amount of the sinterable separation material to be deposited within the layer.

14. The method according to claim 1 , wherein depositing the sinterable separation material includes depositing the sinterable separation material formed from 15-35% by volume ceramic powder and greater than 50% by volume the second removable binder.

15. A method of 3D printing, comprising:
depositing a model material in successive layers to form a part, the model material being a metal composite including greater than 50% by volume metal powder and less than 50% by volume first removable binder;
depositing the model material in successive layers to form a support structure adjacent the part;
depositing a sinterable separation material between a surface of the part and a surface of the support structure, the sinterable separation material formed from 10-40% by volume ceramic powder and greater than 50% by volume second removable binder;
debinding the first removable binder of the model material and the second removable binder of the sinterable separation material;
in a first sintering mode, heating the part, the support structure, and the sinterable separation material at a sintering temperature that sinters the model material while the ceramic powder of the sinterable separation material remains as a debound powder; and
in a second sintering mode, increasing the sintering temperature such that the debound powder of the sinterable separation material sinters to form sintered separation material.

16. The method according to claim 15 , wherein the first removable binder and the second removable binder share more than 80% of their ingredients by volume.

17. The method according to claim 15 , further comprising:
depositing on a build plate the model material in successive layers to form a shrinking platform on which the part and the support structure are formed; and
depositing a sliding release layer below the shrinking platform configured to remain powdered at a sintering temperature of the model material and to promote sliding between the shrinking platform and the build plate during the first sintering mode and the second sintering mode.

18. The method according to claim 15 , wherein, in the second sintering mode, increasing the sintering temperature includes increasing the sintering temperature such that the debound powder of the sinterable separation material sinters and becomes at least one of fragmented, cracked, flaked, and breakable after the second sintering mode.

19. The method according to claim 18 , further comprising removing the sintered separation material.

20. The method according to claim 18 , wherein removing the sintered separation material includes applying mechanical energy to the sintered separation material to separate the sintered separation material from the part.

21. The method according to claim 15 , further comprising forming physical connections between the part and the support structure, the physical connections configured to remain in place throughout the first sintering mode and the second sintering mode and to be separated from the part after the second sintering mode by applying mechanical energy.

22. The method according to claim 21 , wherein the physical connections between the part and the support structure are formed from the model material.

23. The method according to claim 21 , wherein the physical connections between the part and the support structure are formed from the sinterable separation material.

24. The method according to claim 15 , wherein depositing the sinterable separation material includes depositing the sinterable separation material with a first nozzle having a lateral translation speed that is 10-75% of a lateral translation speed of a second nozzle through

Assignees

• Markforged Inc

Inventors

• Mark Gregory Thomas
• Woodruff Rick Bryan
• Chao Michelle Ling

Classifications

• B29C64/40 Primary

  Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof · CPC title

• B29C64/165 Primary

  using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber · CPC title

• B22F10/50

  Treatment of workpieces or articles during build-up, e.g. treatments applied to fused layers during build-up · CPC title

• B22F10/47

  characterised by structural features · CPC title

• B22F10/32

  of the atmosphere, e.g. composition or pressure in a building chamber · CPC title