Fused filament fabrication system configured to fabricate interface layers for breakaway support

Patent metadata

Field	Value
Publication number	US-2017297099-A1
Application number	US-201715469292-A
Country	US
Kind code	A1
Filing date	Mar 24, 2017
Priority date	Apr 14, 2016
Publication date	Oct 19, 2017
Grant date	—

Abstract

A three-dimensional printer uses a fused filament fabrication process to fabricate a net shape object from build materials that can be debound and sintered into a final part. In order to facilitate separation of the object from surrounding support structures, the three-dimensional printer is configured to deposit material between adjacent surfaces of the object and the support that inhibit bonding between adjacent surfaces of the support structure and the object during sintering.

First claim

1 . A printer for three-dimensional fabrication, the printer comprising:
a build plate; a first extruder coupled to a first source of a build material for fabricating an object, the build material including a powdered material for forming the object and a binder system including one or more binders, wherein the one or more binders resist deformation of a net shape of the object during processing of the object into a final part; a second extruder coupled to a second source of an interface material for fabricating an interface layer between the object and an adjacent surface of a support structure, wherein the interface material resists bonding of the object to the support structure during sintering; a robotic system operable to move the first extruder and the second extruder relative to the build plate; and a processor configured by computer executable code to move the robotic system along a build path relative to the build plate while extruding from at least one of the first extruder and the second extruder to fabricate the object on the build plate based on a computerized model of the object.

2 . The printer of claim 1 wherein the first extruder is the second extruder.

3 . The printer of claim 1 further comprising a third extruder coupled to a third source of a support material for fabricating the support structure.

4 . The printer of claim 3 wherein the support material includes an oxygen getter.

5 . The printer of claim 1 further comprising a third extruder coupled to a third source of a second build material for use in multi-material fabrication.

6 . The printer of claim 1 wherein the processor is configured to form the support structure by extruding the build material from the first extruder.

7 . The printer of claim 1 wherein the build material is supplied in at least one of a rod, a spool, a block, and a volume of pellets.

8 . The printer of claim 1 further comprising a supply of preformed blocks of the build material and a second robotic system configured to position one or more of the preformed blocks to form an interior structure within the object.

9 . The printer of claim 1 wherein the interface material includes the binder system of the build material.

10 . The printer of claim 1 wherein the processor is configured to underextrude at least one of the support structure, a surface of the object, and the interface layer to reduce a contact area with an adjacent layer.

11 . The printer of claim 10 wherein the processor is configured to underextrude using at least one of an increased tool speed and a decreased volumetric deposition rate.

12 . The printer of claim 1 wherein the processor is configured to reduce a contact area between the interface layer and one of the object and the support structure by decreasing an extrusion bead size or increasing a spacing between roads of deposited material.

13 . The printer of claim 1 wherein the build material includes a powdered metallurgy material.

14 . The printer of claim 1 wherein the build material includes a metal powder.

15 . The printer of claim 1 wherein the interface material includes a ceramic powder having a higher sintering temperature than the build material.

16 . The printer of claim 1 further comprising a milling tool configured for shaping the build material on the build plate after extrusion from the first extruder and prior to sintering of the object.

17 . The printer of claim 1 further comprising a debinding station configured to remove at least a portion of the binder system from the build material in the object.

18 . The printer of claim 1 further comprising a sintering furnace configured to sinter the powdered material into a densified object.

19 - 30 . (canceled)

Assignees

• Desktop Metal Inc

Inventors

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

Classifications

• B22F1/10

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

• B22F10/40

  Structures for supporting workpieces or articles during manufacture and removed afterwards · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B22F10/62

  by chemical means · CPC title

• B22F10/64

  by thermal means (control of energy beam parameters for post heating B22F10/364) · CPC title