Additive manufacturing using a mobile build volume

Patent metadata

Field	Value
Publication number	US-2018281069-A1
Application number	US-201816002041-A
Country	US
Kind code	A1
Filing date	Jun 7, 2018
Priority date	Jan 13, 2017
Publication date	Oct 4, 2018
Grant date	—

Abstract

The present disclosure generally relates to additive manufacturing systems and methods on a large-scale format. One aspect involves a build unit that can be moved around in three dimensions by a positioning system, building separate portions of a large object. The build unit has an energy directing device that directs, e.g., laser or e-beam irradiation onto a powder layer. In the case of laser irradiation, the build volume may have a gasflow device that provides laminar gas flow to a laminar flow zone above the layer of powder. This allows for efficient removal of the smoke, condensates, and other impurities produced by irradiating the powder (the “gas plume”) without excessively disturbing the powder layer. The build unit may also have a recoater that allows it to selectively deposit particular quantities of powder in specific locations over a work surface to build large, high quality, high precision objects.

First claim

1 . A method for making an object from powder comprising:
(a) moving a build unit over a build area of a work surface, the build unit comprising a gasflow device with a laminar flow zone over the build area, the gasflow device providing substantially laminar gas flow within two inches of, and substantially parallel to, the work surface; (b) irradiating at least a portion of the build area of the work surface with a laser that passes through the laminar flow zone to form a first fused layer; and (c) repeating at least steps (a) through (b) to form the object.

2 . The method of claim 1 , further comprising a step (d) of moving the build unit vertically away from the work surface.

3 . The method of claim 2 , further comprising repeating steps (a) and (b) after step (d).

4 . The method of claim 1 , wherein the gasflow device provides a low oxygen environment around the work surface in a region below the build unit.

5 . The method of claim 4 , wherein the build unit includes a reduced oxygen gas zone above the laminar flow zone.

6 . The method of claim 5 , further comprising a containment zone surrounding at least the build unit and positioning system.

7 . The method of claim 1 , wherein the laser irradiation directing device is within the build unit.

8 . The method of claim 1 , wherein the positioning system allows for rotation of the build unit in the two dimensions that are substantially parallel to the work surface.

9 . The method of claim 1 , wherein the build unit further comprises a powder delivery unit and a recoater arm.

10 . The method of claim 8 , wherein build unit is rotated 90° and moved in a direction perpendicular to the direction of movement in step (a).

11 . The method of claim 1 , further comprising using a second build unit to build at least a portion of a second object on the work surface.

12 . The method of claim 1 , further comprising using a second build unit to build at least a portion of the build envelope.

Assignees

• Gen Electric

Inventors

• Redding Mackenzie Ryan
• Fieldman Zachary David
• Mamrak Justin

Classifications

• B22F12/67

  Blades · CPC title

• B22F12/52

  Hoppers · CPC title

• B22F10/385

  Overhang structures · CPC title

• B22F10/28

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

• B22F12/47

  parallel to the deposition plane · CPC title