Method and apparatus for irradiating a material with an energy beam

Patent metadata

Field	Value
Publication number	US-12564899-B2
Application number	US-201917291800-A
Country	US
Kind code	B2
Filing date	Nov 5, 2019
Priority date	Nov 12, 2018
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

A method and an irradiation device for locally melting a material are described, wherein an area of incidence of the energy beam on the material is moved. In the process, at least one first energy beam and one second energy beam are generated, the second energy beam is moved relative to the first energy beam and the first energy beam and the second energy beam are coupled in a common beam path into an energy beam movement unit in such a way that they are moved together over the material as a combination energy beam.

First claim

The invention claimed is:

1 . A method for irradiating a material with an energy source, wherein an area of incidence of the energy source on the material is moved in a process for locally melting the material, comprising:
producing at least one first energy beam and at least one second energy beam from the energy source, the first energy beam having a first beam intensity profile extending over a first energy beam interior spot extent, the at least one first energy beam further having a perimeter surrounding the first energy beam interior spot extent, the second energy beam having a second beam intensity profile extending over a second energy beam spot extent that is smaller than the first energy beam interior spot extent; and moving the second energy beam within the first energy beam interior spot extent during a melting process, wherein the first energy beam and the second energy beam are coupled into an energy beam movement unit in a common scanning beam path such that the first energy beam and the second energy beam are moved together as a combination energy beam with the second energy beam moving within the first energy beam interior spot extent on a path around and along the perimeter as the combination energy beam traverses over the material.

2 . The method according to claim 1 , wherein the second energy beam is moved relative to the first energy beam at a predetermined relative speed, a magnitude of which is at least 2 times greater than a speed of the first energy beam.

3 . The method according to claim 1 , further comprising intensity modulating the second energy beam depending on a relative position of the second energy beam to the first energy beam and/or depending on a current direction of movement of an area of incidence of the combination energy beam.

4 . The method according to claim 1 ,
wherein the first energy beam and the second energy beam have different intensity profile distributions; wherein the first energy beam has a substantially rotationally symmetrical intensity distribution with respect to a beam axis; and/or wherein the second energy beam has a substantially rotationally symmetrical intensity profile distribution.

5 . The method according to claim 1 , wherein relative movement of the second energy beam relative to the first energy beam and/or intensity modulation of the second energy beam are performed cyclically.

6 . The method according to claim 1 , wherein the second energy beam is moved along a circular path, along an edge of the first beam intensity profile.

7 . The method according to claim 1 , wherein relative movement of the second energy beam with respect to the first energy beam and/or an intensity modulation of the second energy beam occurs such that the combination energy beam moved over the material has an overall intensity profile distribution at the area of incidence on the material in a section plane running perpendicularly to a beam axis of the combination energy beam which integrates, over a time period,
at least one local minimum in a middle region along at least one secant in the section plane; and an intensity profile curve, running along an edge of an overall intensity distribution, having at least at one point, a maximum value, and, in a region opposite the maximum value on the intensity profile curve, a minimum value.

8 . A method for additively manufacturing a product, wherein build-up material is solidified selectively in a build field, the build-up material being irradiated with at least one combination energy beam using the method according to claim 1 .

9 . An irradiation device for irradiating a material with an energy source, wherein an area of incidence from the energy source on the material is moved in a melting process, the irradiation device comprising:
an energy beam source system for generating a first energy beam and a second energy beam, the first energy beam having a first beam intensity profile extending over a first energy beam interior spot extent, the first energy beam having a perimeter surrounding the first energy beam interior spot extent, the second energy beam having a second beam intensity profile extending over a second energy beam interior spot extent that is smaller than the first energy beam interior spot extent, the first beam intensity profile having an intensity along the perimeter that is larger than an intensity along the first beam intensity profile radially inward of the perimeter; a first energy beam movement unit for moving the second energy beam relative to the first energy beam; and an energy beam combination device and a second energy beam movement unit, which are formed and arranged relative to one another such that the first energy beam and the second energy beam are coupled into the second energy beam movement unit in a common beam path such that the first energy beam and the second energy beam are moved together as a combination energy beam over the material, with the second energy beam moving within the first energy beam interior spot extent along the perimeter as the combination energy beam traverses over the material.

10 . The irradiation device according to claim 9 , wherein the energy beam combination device comprises a beam combiner arranged upstream of the second energy beam movement unit and that couples the first energy beam and the second energy beam parallel to one another, wherein the beam combiner comprises a polarizer.

11 . The irradiation device according to claim 9 , wherein the first energy beam movement unit comprises a rotation unit with a rotatable optical element.

12 . The irradiation device according to claim 11 , wherein the first energy beam movement unit has a transmissive beam shift element which is arranged at an incline in a beam path of the second energy beam and rotatably about a rotation axis, wherein the rotation axis runs coaxially to the beam path of the second energy beam; and/or
the rotatable optical element has a reflector which is arranged at an incline in the beam path of the second energy beam and rotatable about a rotation axis, such that, during operation, an outgoing beam path of the second energy beam runs at an angle to the rotation axis, and wherein a further optical element is arranged downstream of the reflector in a further beam path of the second energy beam and, during operation, the further optical element deflects the beam path outgoing from the reflector such that the beam path rotates over a virtual cylinder surface about a virtual rotation axis when a mirror is rotated, and thereby runs parallel to the virtual rotation axis.

13 . An irradiation device according to claim 9 , comprising:
at least one energy beam source system for generating at least one first energy beam and at least one second energy beam; at least one first energy beam movement unit and at least one second energy beam movement unit; and a control device that controls the irradiation device such that the first energy beam and the second energy beam are moved over the material, at least partially superimposed as the combination energy beam and in a manner coordinated with a predetermined scanning speed, wherein the second energy beam is moved relative to the first energy beam at a predetermined relative speed, a magnitude of which is least two times greater than a speed of the first energy beam.

14 . A device for additively manufacturing products in a manufacturing process, in which build-up material is built up and selectively solidified, wherein, for a solidification process, the build-up material is irradiated with at least one energy beam on a build field, wherein an incident area of t

Assignees

• Eos Gmbh Electro Optical Systems

Inventors

• Holfelder Peter
• Witte Armin

Classifications

• B22F10/366

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

• B22F10/36

  of energy beam parameters · CPC title

• B22F12/90

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

• B22F12/49

  Scanners · CPC title

• B22F12/45

  Two or more · CPC title