Apparatus for producing a three-dimensional work piece with improved gas flow

Patent metadata

Field	Value
Publication number	US-11278965-B2
Application number	US-201916410664-A
Country	US
Kind code	B2
Filing date	May 13, 2019
Priority date	Nov 11, 2016
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

An apparatus including a process chamber accommodating a carrier for receiving a raw material powder. An irradiation device of the apparatus is configured to selectively irradiate electromagnetic or particle radiation onto the raw material powder on the carrier in order to produce a work piece by an additive layer construction method, wherein a transmission element allows the transmission of the electromagnetic or particle radiation into the process chamber. The apparatus further includes a gas inlet and a gas outlet for supplying and discharging gas to and from the process chamber which are configured to generate a protective gas stream for protecting the transmission element from being contaminated by impurities present in the process chamber. The gas inlet includes a gas permeable, porous component forming a gas inlet area.

First claim

The invention claimed is:

1. An apparatus for producing a three-dimensional work piece, the apparatus comprising:
a process chamber accommodating a carrier for receiving a raw material powder,
an irradiation device for selectively irradiating electromagnetic or particle radiation onto the raw material powder on the carrier in order to produce a work piece made of said raw material powder by an additive layer construction method,
a transmission element which allows the transmission of the electromagnetic or particle radiation emitted by the irradiation device into the process chamber, and
a gas inlet for supplying gas to the process chamber and a gas outlet for discharging gas from the process chamber which are configured to generate a protective gas stream in the process chamber for protecting the transmission element from being contaminated by impurities present in the process chamber,
wherein
the gas inlet comprises a panel-shaped, gas permeable, porous component provided with openings and forming a gas inlet area of the gas inlet, wherein the panel-shaped gas permeable, porous component of the gas inlet is arranged in a first side wall of the process chamber, the first side wall of the process chamber being arranged opposed to a second side wall of the process chamber accommodating the gas outlet, and
the apparatus further comprises a further gas inlet for supplying gas to the process chamber, the further gas inlet having a gas inlet opening accommodated in the first side wall of the process chamber underneath the panel-shaped, gas permeable, porous component of the gas inlet, and

a baffle plate upstream of the gas inlet to disperse the gas across the panel-shaped, gas permeable, porous component of the gas inlet.

2. The apparatus according to claim 1 ,
wherein the panel-shaped, gas permeable, porous component of the gas inlet comprises a sintered material and/or a fibrous material.

3. The apparatus according to claim 1 ,
wherein the panel-shaped, gas permeable, porous component of the gas inlet is made of a material including stainless steel, bronze, titanium and/or a nickel-based alloy.

4. The apparatus according to claim 1 ,
wherein the panel-shaped, gas permeable, porous component of the gas inlet has a porosity between 20% and 90% and/or a pore size between 1 μm to 10 μm.

5. The apparatus according to claim 1 ,
wherein the panel-shaped, gas permeable, porous component of the gas inlet comprises a plurality of sections with different flow resistances for gases flowing through.

6. The apparatus according to claim 1 ,
wherein the gas inlet and the gas outlet are configured and arranged in such a manner that a first gas flow of the protective gas stream is generated having a flow directional component facing away from the transmission element, and wherein the further gas inlet and the gas outlet are configured and arranged in such a manner that a second gas flow of the protective gas stream across the carrier is generated.

7. The apparatus according to claim 1 ,
further comprising a control unit which is adapted to control the supply of gas to the process chamber in such a manner that a volume flow of gas to the process chamber via the gas inlet is larger than a volume flow of gas to the process chamber via the further gas inlet.

8. The apparatus according to claim 1 ,
further comprising a gas inlet channel connected to the gas inlet and configured to supply gas to the process chamber via the gas inlet, the gas inlet channel having a first portion with a first flow cross-section and a second portion downstream of the first portion with a second flow cross-section larger than the first flow cross-section.

9. The apparatus of claim 2 , wherein the panel-shaped, gas permeable, porous component of the gas inlet comprises at least one of a fibrous web and an open-cell foam.

10. The apparatus of claim 4 , wherein the panel-shaped, gas permeable, porous component of the gas inlet has a porosity of 40%.

11. The apparatus of claim 2 , wherein the panel-shaped, gas permeable, porous component of the gas inlet comprises a metal foam.

12. The apparatus according to claim 8 ,
wherein the second portion comprises a dispersion unit for dispersing a gas flow directed from the first portion into the second portion.

13. The apparatus according to claim 1 , wherein:
the further gas inlet has a slit-shaped gas inlet opening accommodated in the first side wall of the process chamber underneath the panel-shaped, gas permeable, porous component of the gas inlet; and
the gas outlet is a slit-shaped gas outlet opening accommodated in the second side wall of the process chamber at the same height as the slit-shaped gas inlet opening of the further gas inlet in the first side wall.

14. The apparatus according to claim 13 , wherein the slit-shaped gas outlet opening extends across an entire width of the second side wall and the slit-shaped gas inlet opening extends across an entire width of the first side wall.

15. The apparatus according to claim 1 , wherein the panel-shaped, gas permeable, porous component of the gas inlet extends across an entire width of the first side wall and across a height of the first side wall from the gas inlet opening of the further inlet to distribute the protective gas stream homogeneously across the entire width and the height.

16. An apparatus for producing a three-dimensional work piece, the apparatus comprising:
a process chamber accommodating a carrier for receiving a raw material powder,
an irradiation device for selectively irradiating electromagnetic or particle radiation onto the raw material powder on the carrier in order to produce a work piece made of said raw material powder by an additive layer construction method,
a transmission element which allows the transmission of the electromagnetic or particle radiation emitted by the irradiation device into the process chamber, and
a gas inlet for supplying gas to the process chamber and a gas outlet for discharging gas from the process chamber which are configured to generate a protective gas stream in the process chamber for protecting the transmission element from being contaminated by impurities present in the process chamber,
wherein
the gas inlet comprises a panel-shaped, gas permeable, porous component provided with openings and forming a gas inlet area of the gas inlet, wherein the panel-shaped gas permeable, porous component of the gas inlet is arranged in a first side wall of the process chamber, the first side wall of the process chamber being arranged opposed to a second side wall of the process chamber accommodating the gas outlet, and
the apparatus further comprises a further gas inlet for supplying gas to the process chamber, the further gas inlet having a gas inlet opening accommodated in the first side wall of the process chamber underneath the panel-shaped, gas permeable, porous component of the gas inlet,

wherein the panel-shaped, gas permeable, porous component of the gas inlet extends across an entire width of the first side wall and across a height of the first side wall from the gas inlet opening of the further inlet so the protective gas stream is homogeneously distributed across the entire width and the height.

Assignees

• SLM Solutions Group AG

Inventors

• Huebinger Isabell
• Wilkes Jan
• Iqbal Naveed
• Wiesner Andreas
• Gieser Eduard

Classifications

• B29C64/153 Primary

  using layers of powder being selectively joined, e.g. by selective laser sintering or melting · CPC title

• B33Y10/00 Primary

  Processes of additive manufacturing · CPC title

• B22F10/322

  of the gas flow, e.g. rate or direction · CPC title

• B22F12/70

  Gas flow means · CPC title

• B22F12/49

  Scanners · CPC title