Layer-forming nozzle exit for fused filament fabrication process

Patent metadata

Field	Value
Publication number	US-2018304370-A1
Application number	US-201816024143-A
Country	US
Kind code	A1
Filing date	Jun 29, 2018
Priority date	Dec 16, 2015
Publication date	Oct 25, 2018
Grant date	—

Abstract

A printer fabricates an object from a computerized model using a fused filament fabrication process. A former extending from a nozzle of the printer supplements a layer fusion process by applying a normal force on new material as it is deposited to form the object. The former may use a variety of techniques such as heat and rolling to improve physical bonding between layers.

First claim

What is claimed is:

1 . A method comprising:
moving a first filament of a first build material, in a first direction toward a first nozzle, along a first feed path extending from a first spool of the first filament to the first nozzle, the first filament including first metal particles dispersed in a first binder system; moving a second filament of a second build material, in a second direction toward a second nozzle, along a second feed path extending from a second spool of the second filament of the second build material to the second nozzle, the second filament including second metal particles dispersed in a second binder system, the second metal particles smaller than first metal particles; and with the first build material at a first extrusion temperature and the second build material at a second extrusion temperature, extruding the first build material and the second build material through the respective one of the first nozzle and the second nozzle toward a build plate, the extrusion of the first build material and the second build material forming a three-dimensional object.

2 . The method of claim 1 , wherein a concentration of the first metal particles in the first binder system is greater than about 50 percent by volume.

3 . The method of claim 1 , wherein a concentration of the second metal particles in the second binder system is greater than about 50 percent by volume.

4 . The method of claim 1 , wherein the first filament and the second filament have the same glass transition temperature.

5 . The method of claim 1 , wherein the first binder system and the second binder system have the same composition.

6 . The method of claim 5 , wherein the first binder system and the second binder system each include a bulk binder and a backbone binder separately, the bulk binder and the backbone binder separately removable from the three-dimensional object.

7 . The method of claim 1 , wherein the first extrusion temperature is substantially equal to the second extrusion temperature.

8 . The method of claim 1 , wherein the first metal particles and the second metal particles have the same composition.

9 . The method of claim 1 , wherein the first metal particles have an average size of greater than about 10 microns and less than about 20 microns.

10 . The method of claim 1 , wherein the second metal particles have an average size of greater than about 1 micron and less than about 10 microns.

11 . The method of claim 1 , further comprising increasing ductility of each of the first filament and the second filament along a respective one of the first feed path and the second feed path.

12 . The method of claim 11 , wherein increasing ductility of the first filament and the second filament includes heating at least one of the first filament and the second filament from a brittle state to a plastic state.

13 . The method of claim 11 , wherein increasing ductility of the first filament and the second filament includes resistively heating at least one of the first filament or the second filament through contact pads disposed along a corresponding at least one of the first feed path and the second feed path.

14 . The method of claim 11 , wherein increasing ductility of the first filament and the second filament includes inductively heating at least one of the first filament or the second filament via one or more electromagnets disposed along a corresponding at least one of the first feed path and the second feed path.

15 . The method of claim 11 , wherein increasing ductility of the first filament and the second filament includes directing heat into at least one of the first filament or the second filament via a corresponding drive train in contact with the respective at least one of the first filament and the second filament.

16 . The method of claim 1 , wherein extruding the first build material and the second build material forms the three-dimensional object with first build material and the second build material adjacent to one another along the three-dimensional object.

17 . The method of claim 16 , wherein extruding the first build material and the second build material forms the three-dimensional object with the second build material defining an outer portion of the three-dimensional object.

18 . The method of claim 16 , wherein extruding the first build material and the second build material forms the three-dimensional object with the first build material along an inner portion of the three-dimensional object.

19 . The method of claim 1 , wherein extruding the first build material and the second build material includes forming at least one of the first build material or the second build material into a respective paste having non-Newtonian fluid properties.

20 . The method of claim 1 , further comprising debinding the first binder system and the second binder system from the three-dimensional object to form a brown part.

21 . The method of claim 20 , further comprising densifying the first metal particles and the second metal particles in the brown part to form a final part.

Assignees

• Desktop Metal Inc

Inventors

• Myerberg Jonah Samuel
• Fulop Ricardo
• Gibson Michael Andrew
• Hart Anastasios John
• Fontana Richard Remo
• Schuh Christopher Allan
• Chiang Yet-Ming
• Verminski Matthew David
• Schmitt Peter Alfons
• Sachs Emanuel Michael
• Chin Ricardo

Classifications

• B22F10/30

  Process control · CPC title

• B22F12/57

  Metering means · CPC title

• B22F10/43

  characterised by material · CPC title

• B22F3/24 Primary

  After-treatment of workpieces or articles {(B22F3/1146 takes precedence)} · CPC title

• B22F10/18

  by mixing binder with metal in filament form, e.g. fused filament fabrication [FFF] · CPC title