Additive fabrication of sinterable metallic parts via application of directed energy

Patent metadata

Field	Value
Publication number	US-2020298475-A1
Application number	US-202016824987-A
Country	US
Kind code	A1
Filing date	Mar 20, 2020
Priority date	Mar 20, 2019
Publication date	Sep 24, 2020
Grant date	—

Abstract

According to some aspects, techniques are provided for fabricating sinterable metallic parts through the application of directed energy to a build material. In particular, applying energy to a build material comprising a polymer mixed with a metal powder may cause the polymer to form a cohesive structure with the metal powder. As a result, the polymer acts as a “glue” to produce a metallic green part without local melting of the metal. The green part may subsequently be sintered to remove the polymer and produce a fully dense metal part. Optionally, a step of debinding may also be performed prior to, or simultaneously with, sintering.

First claim

What is claimed is:

1 . A method of fabricating an object via additive fabrication, the method comprising:
depositing a build material into a build region of an additive fabrication device, the build material comprising a powder including a metal and a polymer; and directing, by the additive fabrication device, energy onto the deposited build material to cause at least some of the polymer to adhere to other portions of the polymer and/or the metal.

2 . The method of claim 1 , wherein directing said energy onto the deposited build material causes the at least some of the polymer to melt and adhere to the other portions of the polymer and/or the metal.

3 . The method of claim 1 , wherein directing said energy onto the deposited build material causes the at least some of the polymer to undergo heat-induced polymerization.

4 . The method of claim 1 , wherein directing said energy onto the deposited build material causes photopolymerization of the at least some of the polymer.

5 . The method of claim 1 , wherein the build material comprises metal particles coated with the polymer.

6 . The method of claim 1 , wherein the build material comprises metal particles and polymer particles.

7 . (canceled)

8 . The method of claim 1 , wherein the polymer comprises one or more thermoplastics.

9 . The method of claim 1 , wherein the polymer comprises a wax.

10 . The method of claim 1 , wherein the polymer comprises polypropylene, polyethylene and/or paraffin.

11 . The method of claim 1 , wherein the polymer comprises one or more copolymers.

12 - 13 . (canceled)

14 . The method of claim 1 , further comprising fabricating a sinterable metallic part through repetition of the acts of depositing build material and directing energy onto the build material.

15 . The method of claim 14 , further comprising sintering the sinterable metallic part in a furnace.

16 . The method of claim 1 , wherein directing energy onto the deposited build material comprises directing radiation from a laser onto the deposited build material.

17 . The method of claim 16 , wherein the radiation produced by the laser comprises visible light.

18 . The method of claim 1 , wherein directing energy onto the deposited build material comprises directing an x-ray beam onto the deposited build material.

19 . The method of claim 1 , wherein directing energy onto the deposited build material comprises directing an array of light sources onto the deposited build material.

20 . (canceled)

21 . The method of claim 1 ,
wherein depositing the build material into the build region comprises filling a build volume with the build material, and wherein directing energy onto the deposited build material comprises directing a plurality of energy sources onto the deposited build material to cause the at least some of the polymer to adhere to other portions of the polymer and/or the metal in locations in which the plurality of energy sources constructively interfere with one another.

22 . The method of claim 1 ,
wherein depositing the build material into the build region comprises filling a build volume with the build material, and wherein directing energy onto the deposited build material comprises projecting a plurality of images through the build volume along different axes.

23 . The method of claim 22 , wherein projecting a plurality of images through the build volume along different axes comprises projecting one or more of the plurality of images simultaneously through the build volume.

24 . The method of claim 1 , wherein the build material further comprises one or more flow improvers.

25 - 63 . (canceled)

Assignees

• Desktop Metal Inc

Inventors

• Myerberg Jonah Samuel
• Hart Anastasios John

Classifications

• B22F1/10

  Metallic powder containing lubricating or binding agents; Metallic powder containing organic material · CPC title

• B22F1/102

  Metallic powder coated with organic material · CPC title

• B33Y70/10

  Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials · CPC title

• B22F10/73

  of powder · CPC title

• B22F12/45

  Two or more · CPC title