Apparatus for treating raw-material powder, apparatus for treating raw-material powder, and method for producing object

Patent metadata

Field	Value
Publication number	US-10421156-B2
Application number	US-201615373216-A
Country	US
Kind code	B2
Filing date	Dec 8, 2016
Priority date	Dec 10, 2015
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

A method for treating a raw-material powder includes forming a layer of the raw-material powder and removing oxide film formed on a surface of the raw-material powder from which the layer has been formed.

First claim

What is claimed is:

1. A method for treating a raw-material powder in an object production system that uses powder bed fusion, the method comprising:
forming a first layer of the raw-material powder; and
removing oxide film formed on a surface of the raw-material powder from which the first layer has been made through chemical reduction,
wherein the removal of the oxide film is performed by generating plasma through application of an AC voltage to an electrode in contact with the first layer in an atmosphere containing hydrogen and/or an inert element.

2. The method according to claim 1 for treating a raw-material powder, wherein: in the formation of the first layer, the first layer is formed in an evacuable enclosure; and
the removal of the oxide film is performed with the enclosure evacuated to a sub-atmospheric pressure.

3. The method according to claim 2 for treating a raw-material powder, wherein the sub-atmospheric pressure is a pressure of 10 Pa or more and less than 10 kPa.

4. The method according to claim 2 for treating a raw-material powder, the method further comprising creating an atmosphere by evacuating the enclosure to a first pressure and then delivering an inert element into the enclosure to create the atmosphere of a second pressure that is higher than the first pressure and lower than atmospheric pressure.

5. The method according to any one of claim 2 for treating a raw-material powder, wherein the first layer is formed in a powder container located in the enclosure and electrically insulated from the enclosure.

6. The method according to claim 1 for treating a raw-material powder, wherein after the removal of the oxide film, a second layer is formed on the first layer.

7. The method according to claims 1 a for treating a raw-material powder, wherein the generation of plasma is performed with the first layer heated using a heater or an energy beam.

8. The method according to claim 1 for treating a raw-material powder, wherein the raw-material powder is metal particles formed by water atomization.

9. A method for producing an object using powder bed fusion, the method comprising:
treating a raw-material powder by the method according to claim 1 ; and
shaping with a beam including solidifying, through irradiation with an energy beam, the raw-material powder from which the oxide film has been removed.

Assignees

• Canon Kk

Inventors

• Kamachi Koh
• Kitani Koji

Classifications

• C01B33/02 Primary

  Silicon (forming single crystals or homogeneous polycrystalline material with defined structure C30B) · CPC title

• B22F12/49

  Scanners · CPC title

• B22F10/32

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

• B22F10/28

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

• B23K26/342 Primary

  Build-up welding · CPC title