Continuous exposure

Patent metadata

Field	Value
Publication number	US-11550295-B2
Application number	US-201716497477-A
Country	US
Kind code	B2
Filing date	Mar 31, 2017
Priority date	Mar 31, 2017
Publication date	Jan 10, 2023
Grant date	Jan 10, 2023

Abstract

A method for providing control data for manufacturing at least one three-dimensional object by means of a layer-wise solidification of a building material in an additive manufacturing apparatus is provided. The method includes at least the following steps: a) determining the locations corresponding to the cross section of the at least one object, b) determining at least two different regions to be solidified in said at least one layer, wherein said at least two regions are chosen from the group of: sandwiched region, down-facing region and up-facing region, c) defining a scanning sequence for the beam so as to solidify the building material at least at the locations corresponding to said portion of the cross section of the object, wherein at an interface between a first and a second region differing from each other a scan line of the beam is continuous and at least one beam parameter value is changed.

First claim

The invention claimed is:

1. A method for providing control data for manufacturing at least one three-dimensional object by layer-wise solidification of a building material in an additive manufacturing apparatus, wherein the apparatus comprises an irradiation device for directing a beam of electromagnetic or particle radiation onto a layer of the building material at locations corresponding to a cross-section of the at least one object in the layer so as to solidify the building material at the locations, wherein the irradiation device is adapted to scan the beam in at least one of hatch lines, contours, and polylines over the layer, wherein the method includes at least the following steps:
a) determining the locations corresponding to the cross section of the at least one object for at least one of a plurality of layers of building material;
b) determining at least two different regions to be solidified in the at least one layer, the at least two regions corresponding to at least a portion of the cross-section of the object in the layer, wherein the at least two regions are selected from the group consisting of a sandwiched region, a down-facing region, and an up-facing region;
c) assigning a pre-defined set of beam parameter values to each region, the pre-defined set of beam parameter values being selected such that the energy input per unit area in the down- facing regions is lower than in the sandwiched regions and/or the energy input per unit area in the up-facing regions is higher than in the sandwiched regions;
d) defining, for the at least one layer, a scanning sequence for the beam so as to solidify the building material at least at the locations corresponding to the portion of the cross section of the object, wherein the scanning sequence is defined such that a scan line of the beam is moved without interruption across an interface between a first and a second region differing from each other, wherein at least one beam parameter value is changed at the interface in accordance with the pre-defined set of beam parameter values when the scan line passes from the first region to the second region; and
providing control data for the control of the irradiation device in the additive manufacturing apparatus in accordance with the scanning sequence defined in step d) for a solidification of the building material in the at least one layer.

2. The method according to claim 1 , wherein the at least one beam parameter value that is changed at the interface is selected from the group consisting of a beam power, a beam diameter, a beam shape, a position of the focus of the beam, and a scanning velocity.

3. The method according to claim 1 , wherein the first region and the second region are scanned using hatch lines.

4. The method according to claim 3 , wherein the distance between neighboring hatch lines is essentially constant.

5. The method according to claim 1 , wherein the first region and the second region are scanned using contours.

6. The method according to claim 1 , wherein the radiation is electromagnetic radiation supplied by a laser.

7. The method according to claim 1 , wherein the building material is a metal powder.

8. A method for manufacturing at least one three-dimensional object by layer-wise solidification of a building material in an additive manufacturing apparatus, the method comprising the following steps:
receiving control data provided in a method according to claim 1 , and
manufacturing the three-dimensional object on the basis of the control data by repeating the steps of applying layers of the building material and selectively solidifying the layers until the at least one three-dimensional object is completed.

9. A control unit for an additive manufacturing apparatus that is adapted to carry out the method according to claim 1 .

10. A method for providing control data for manufacturing at least one three-dimensional object by layer-wise solidification of a building material in an additive manufacturing apparatus, wherein the apparatus comprises an irradiation device for directing a beam of electromagnetic or particle radiation onto a layer of the building material at locations corresponding to a cross-section of the at least one object in the layer so as to solidify the building material at the locations, wherein the irradiation device is adapted to scan the beam in at least one of hatch lines, contours, and polylines over the layer, wherein the method includes at least the following steps:
a) determining the locations corresponding to the cross section of the at least one object for at least one of a plurality of layers of building material;
b) determining at least two different regions to be solidified in the at least one layer, the at least two regions corresponding to at least a portion of the cross-section of the object in the layer, wherein the at least two regions are selected from the group consisting of a sandwiched region, a down-facing region and an up-facing region;
c) defining, for the at least one layer, a scanning sequence for the beam so as to solidify the building material at least at the locations corresponding to the portion of the cross section of the object, wherein the scanning sequence is defined such that the first region and the second region are scanned using polylines and a scan line of the beam is moved without interruption across an interface between a first and a second region differing from each other, wherein at least one beam parameter value is changed at the interface; and
providing control data for the control of the irradiation device in the additive manufacturing apparatus in accordance with the scanning sequence defined in step d) for a solidification of the building material in the at least one layer.

Assignees

• Eos Gmbh Electro Optical Systems

Inventors

• Heikkinen Hannu
• Syvänen Tatu
• Göth Michael
• Hümmeler Ludger
• Hoferer Thomas

Classifications

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title

• G05B2219/49018

  Laser sintering of powder in layers, selective laser sintering SLS · CPC title

• B22F10/366

  Scanning parameters, e.g. hatch distance or scanning strategy · CPC title

• B22F10/30

  Process control · CPC title

• G05B19/40937 Primary

  concerning programming of machining or material parameters, pocket machining · CPC title