Method and device for determining a contour, at least in regions, of at least one additively manufactured component layer

Patent metadata

Field	Value
Publication number	US-10070069-B2
Application number	US-201615152825-A
Country	US
Kind code	B2
Filing date	May 12, 2016
Priority date	May 19, 2015
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

The invention relates to a method for the determination, at least in regions, of a contour of at least one additively manufactured component layer, in which a contour line of the component layer is traveled over, at least in regions, by a laser beam, and a time exposure of the traveled contour line is produced by a camera system. The invention further relates to a device for the determination, at least in regions, of a contour of at least one additively manufactured component layer. For this purpose, the device comprises at least one laser system, by which a contour line of the component layer can be traveled over, at least in regions, by a laser beam, and a camera system, which is designed to produce a time exposure of the contour line traveled over by the laser beam.

First claim

What is claimed is:

1. A method for the determination, at least in regions, of a contour of at least one additively manufactured component layer, comprising the steps of:
creating a component layer by additive manufacturing;
traveling over a contour line of the component layer, at least in regions, by a laser beam;
producing a time exposure by capturing a single image of the laser beam travel over the contour line by a camera system; and
evaluating the quality of the contour line of the component layer from the single image of the laser beam,
wherein a mean speed with which the laser beam travels over the contour line is adjusted to a higher value than a mean speed that was used for the additive manufacture of the component layer, and/or in that the speed of the laser beam is varied one or more times during its travel over the contour line, and
wherein the mean speed with which the laser beam travels over the contour line is adjusted to a value between 900 mm/s and 3000 m/s and/or to a value that corresponds to at least 1.1 times the speed that was used for the additive manufacture of the component layer.

2. The method according to claim 1 , wherein, when the contour line is traveled, a mean power of the laser beam is adjusted to a lower value than a mean power that was used for the additive manufacture of the component layer, and/or in that the power during the travel of the contour line is varied one or more times.

3. The method according to claim 2 , wherein, when the contour line is traveled over, the power is adjusted to a value between 50 W and 200 W, and/or corresponds to a value that is at most 0.9 times the power that was used for the additive manufacture of the component layer.

4. The method according to claim 1 , wherein a recording time of the time exposure is adjusted to a value that lies between 0.5 second and 60 seconds, and/or in that a recording time of the time exposure is adjusted in such a way that at least a quality-relevant region of the contour line is imaged completely on the time exposure.

5. The method according to claim 1 , wherein an optical tomography device is used as the camera system.

6. The method according to claim 1 , wherein the time exposure is subjected to an edge detection method by a computing device and/or is combined with at least one further time exposure by the computing device to form an image stack.

7. The method according to claim 1 , wherein, on the basis of at least one time exposure, a quality evaluation of the contour line of the component layer is carried out.

8. The method according to claim 7 , wherein the component layer is classified as being qualitatively not OK when a quality defect from the following group is present: inadmissible dimensional deviation of the contour line, irregular shape of the contour line, inadmissible interruption of the contour line, and inadmissible intensity fluctuations along the contour line; or the contour line is classified as being qualitatively OK when no quality defect from the following group is present: inadmissible dimensional deviation of the contour line, irregular shape of the contour line, inadmissible interruption of the contour line, and inadmissible intensity fluctuations along the contour line.

9. A device for the determination, at least in regions, of a contour of at least one additively manufactured component layer, comprising:
at least one laser system, by which a contour line of the component layer can be traveled over, at least in regions, by a laser beam; and
a camera system, which is configured and arranged to produce a time exposure, in a single image, of the contour line that is traveled over by the laser beam, the single image enabling the evaluation and determination of the quality of the contour line of the component layer,
wherein the laser beam is configured and arranged to have a mean speed that travels over the contour line adjusted to a higher value than a mean speed that was used for the additive manufacture of the component layer, and/or in that the speed of the laser beam is configured and arranged to be varied one or more times during its travel over the contour line, and
wherein the mean speed with which the laser beam travels over the contour line is configured and arranged to be adjusted to a value between 900 mm/s and 3000 m/s and/or to a value that corresponds to at least 1.1 times the speed that was used for the additive manufacture of the component layer.

10. The device according to claim 9 , further comprising:
a synchronization device, by which the camera system can be actuated in such a way that the time exposure can be started and/or stopped depending on an operating state of the laser system.

11. The device according to claim 9 , wherein the camera system comprises an optical tomography device and/or a camera with a resolution of at least 4 megapixels and/or a camera with a dynamic range of at least 14 bits, and/or a camera with a spectral sensitivity in the visible and/or infrared region(s).

12. The device according to claim 9 , further comprising:
a computing device, by which the time exposure can be subjected to an edge detection method and/or by which the time exposure can be combined with at least one other time exposure to form an image stack and/or by which a quality evaluation of the contour line of the component layer can be carried out on the basis of at least one time exposure.

13. The device according to claim 9 , further comprising:
an additive laser sintering and/or laser melting device, by which the at least one component layer can be manufactured.

Assignees

• MTU Aero Engines AG

Inventors

• Bamberg Joachim
• Zenzinger Guenter

Classifications

• B22F12/90

  Means for process control, e.g. cameras or sensors · CPC title

• B22F10/85

  for controlling or regulating additive manufacturing processes · CPC title

• B22F10/38

  to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures · CPC title

• B22F10/36

  of energy beam parameters · CPC title

• B22F10/28

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