Description

Conventional infrared lasers (1070 nm) are not ideal for processing materials such as copper or gold. The reason for this is the corresponding high reflectivity of the aforementioned materials for infrared radiation. Since 2017, so-called “green lasers” (wavelengths around 500 nm [1]) are available for welding processes and additive manufacturing technologies, viz. laser powder bed fusion (LPBF) and laser metal deposition (LMD). These lasers are especially designed for the processing of highly reflective materials and have been recently used for the fabrication of specimens from pure copper.

Due to process reasons, only one alloy is typically used for the manufacturing of components if powder bed based methods (LPBF) are applied. For many components, however, it is the combination of different materials (differences in thermo-physical properties) that leads to an improvement in the component performance. The LMD-process, in contrast to LPBF, can be adjusted with relative low efforts for the processing of two or more different materials. This offers new possibilities for the functionalization of parts that are already fabricated through a combination of subtractive and additive technologies (hybrid manufacturing). A mould insert for polymer injection molding will be presented. It was produced by using a combination of different processes (subtractive, additive) and materials (pure copper, steel 1.2764). For a conventionally manufactured basic body (1.2764), copper cores were integrated in the corner areas by means of LMD. The cladding of the cores with 1.2764 was carried out with regard to the basic body and guaranteed dimensional accuracy for further processing. In order to improve the flow of coolant to the copper cores in the later application, the upper part of the mould insert with conformal cooling channels was manufactured using LPBF. The entire tool insert demonstrator was then finished and case-hardened. Initial tests under real conditions on the overall component are intended to prove full functionality. Simultaneously, we discuss the added value of the hybrid manufacturing approach that was funded by the Federal Ministry of Education and Research (BMBF) in Germany as part of the AGENT-3D project IMProVe.

Contributing Authors

  • Stefan Polenz
    Fraunhofer Institute for Material and Beam Technology
  • Christian Kolbe
    FKT Formenbau und Kunststofftechnik GmbH
  • Florian Bittner
    Fraunhofer Institute for Machine Tools and Forming Technology
  • Elena López
    Fraunhofer Institute for Material and Beam Technology
  • Frank Brueckner
    Fraunhofer Institute for Material and Beam Technology | Luleå University of Technology
  • Christoph Leyens
    Fraunhofer Institute for Material and Beam Technology | Technische Universität Dresden
Stefan Polenz
Fraunhofer Institute for Material and Beam Technology
Elena López
Fraunhofer Institute for Material and Beam Technology
Track: Laser Additive Manufacturing
Session: Directed Energy Deposition Materials Technology
Day of Week: Tuesday
Date/Time:
Location:

Keywords

  • Copper Laser Processing
  • Green Laser
  • Hybrid Manufacturing
  • Laser Metal Deposition