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WO-2026092887-A1 - APPARATUS AND METHOD FOR LASER CLADDING

WO2026092887A1WO 2026092887 A1WO2026092887 A1WO 2026092887A1WO-2026092887-A1

Abstract

The invention relates to an apparatus (10) for laser cladding having the features of claim 1 and to a method for laser cladding having the features of the additional independent claim.

Inventors

  • SCHOLZ, ANDREAS
  • Hellstern, Julian
  • SAUTTER, Bjoern
  • BROGHAMMER, GERHARD
  • FLAMM, Daniel
  • PANG, Hao
  • SPEKER, NICOLAI
  • HESSE, TIM

Assignees

  • TRUMPF Laser- und Systemtechnik SE

Dates

Publication Date
20260507
Application Date
20250821
Priority Date
20241029

Claims (14)

  1. 1. Device (10) for laser cladding comprising: a material powder nozzle (12) for generating and focusing a material powder jet (14) in a process area (16), a laser device (18) for generating a first laser spot (20) and a second laser spot (22) in the process area (16), wherein the device (10) is configured such that the first laser spot (20) and the second laser spot (22) generate a common asymmetric laser intensity profile (24) in the process area (16).
  2. 2. Device (10) according to claim 1, characterized in that the laser intensity profile (24) is asymmetrically designed along a track offset direction (26).
  3. 3. Device (10) according to claim 1 or 2, characterized in that the second laser spot (22) is arranged trailing or leading the first laser spot (20) with respect to a feed direction (28).
  4. 4. Device (10) according to one of the preceding claims, characterized in that an intensity (29) of the second laser spot (22) is greater by a factor of 1.2 to 3, preferably 1.2 to 1.5, than an intensity (27) of the first laser spot (20) .
  5. 5. Device (10) according to the preceding claim, characterized in that the intensity (27) of the The intensity of the first laser spot (20) and/or the intensity (29) of the second laser spot (22) can each be adjusted.
  6. 6. Device (10) according to one of the two preceding claims, characterized in that the intensity (27) of the first laser spot (20) and/or the intensity (29) of the second laser spot (22) each exhibit an asymmetric intensity distribution.
  7. 7. Device (10) according to one of the preceding claims, characterized in that the second laser spot (22) is arranged outside the material powder jet (14) and/or a focus of the material powder jet (14).
  8. 8. Device (10) according to one of the preceding claims, characterized in that the second laser spot (22) is smaller than the first laser spot (20) .
  9. 9. Device (10) according to one of the preceding claims, characterized in that the first laser spot (20) and the second laser spot (22) touch exclusively at one point or partially, in particular completely, overlap.
  10. 10. Device (10) according to one of the preceding claims, characterized in that the first laser spot (20) and/or the second laser spot (22) are each formed from several individual laser spots (21).
  11. 11. Device (10) according to one of the preceding claims, characterized in that the first laser spot (20) and/or the second laser spot (22) each have a square, rectangular or hexagonal shape.
  12. 12. Laser cladding process comprising the following steps: Generating and focusing a material powder jet (14) in a process area (16) ; Generating a first laser spot (20) in the process area (16) ; Generating a second laser spot (22) in the process area (16) ; Generating a common asymmetric laser intensity profile (24) using the first laser spot (20) and the second laser spot (22) .
  13. 13. Method according to claim 12, characterized by the step: Setting an intensity and/or an intensity distribution of the first laser spot (20) and/or the second laser spot (22) .
  14. 14. A method according to claim 12 or 13, characterized in that a device (10) according to one of claims 1 to 11 is used to carry out the method. ```

Description

2024P00190WO 21 . August 2025 Title: Device and method for laser cladding Description The invention relates to a device for laser cladding with features of claim 1 and a method for laser cladding with features of the dependent claim. In laser powder deposition welding, a component is exposed to a powder jet, which is then melted and welded onto the component by means of a laser beam. This allows, for example, the creation of a coating on a component. Depending on the material being welded and the selected process parameters, a rough and wavy surface or outgassing in the bonding area may occur. A rough adhesive layer can promote bonding defects between the adhesive layer and the wear-resistant layer, as the resulting height differences in the layer surface are less readily wetted by the melt than a smooth layer surface. Furthermore, outgassing between the substrate and the adhesive layer can occur due to high laser beam intensity. With a rough wear-resistant layer, a greater feed rate is required in the subsequent grinding process to meet the requirements for dimensional accuracy and surface finish. The roughness of the bonding layer can be reduced by adjusting the process parameters in laser powder deposition welding. For example, the fluence of each pass can be increased by reducing the feed rate while maintaining a constant deposition rate. Alternatively, reducing the carrier gas can result in a lower particle velocity and thus a higher particle temperature. Both strategies can lead to a lower melt viscosity, which improves surface wetting. In both cases, the roughness is reduced, but the waviness of the layer increases, as does the risk of irregularities such as outgassing/pores in the layer. Adjusting the carrier gas can also lead to increased soot formation during the process, thus reducing nozzle life. It is therefore an object of the present invention to provide a device and a method for laser cladding, whereby the above disadvantages are eliminated. The above problem is solved by a device for laser cladding with the features of claim 1. The laser cladding can be high-speed laser powder cladding. Laser cladding can be used, for example, for coating brake discs. The device includes a material powder nozzle. The material powder nozzle is configured to generate and focus a material powder jet in a process area. The device includes a laser unit. The laser device is set up to generate a first laser spot and a second laser spot in the process area. The device is set up such that the first laser spot and the second laser spot generate a common asymmetric laser intensity profile in the process area. This allows for the smoothing of a layer surface, such as an adhesive layer and/or a wear-resistant layer, using simple means. It can improve the bonding between the interlayer and the bond between the adhesive and the wear-resistant layer. Outgassing can be reduced by decreasing the laser intensity in the area of the thermally sensitive substrate. The grinding effort required after laser cladding can be reduced. In some cases, preheating of the process area can be omitted. In this context, the process area can refer to an area on the workpiece or component to be processed or coated, in which the material (powder) is melted or welded. In this context, a laser spot refers in particular to a laser beam focused on a surface. The common asymmetric laser intensity profile can represent a common cross-section through the first laser spot and the second laser spot. In other words, the common asymmetric laser intensity profile can consist of a The cross-section of the first laser spot and a cross-section of the second laser spot are formed, wherein the cross-sections of the first and second laser spots are oriented collinearly. The common asymmetric laser intensity profile can, in particular, be uninterrupted. The laser device can have at least one laser with a wavelength range of 0.8 pm to 2 pm (micrometers) and/or a beam quality (beam parameter product) of 4 mm*mrad to 400 mm*mrad (millimeters*milliradians), preferably 4 mm*mrad to 55 mm*mrad. The material powder can be a metal powder. The material powder can be transported or blown into the process area by means of a (carrier) gas jet. According to a further development of the device, the laser intensity profile can be asymmetrical along a track offset direction. The track offset direction can be oriented perpendicular to a welded material track and/or point from the process area in a direction where no material powder has yet been applied. The track offset direction can be oriented parallel to a surface of the workpiece to be coated or processed. The track offset direction is specifically oriented in the direction of the track offset. This allows the melting of the material powder to be further optimized. According to a further development of the device, the laser intensity profile can be axially symmetric along a track offset direction. According to a further de