Description

Copper-based materials in combination with steels are of great interest for various applications in industry, such as tool manufacture due to their high thermal conductivity. Additive manufacturing (AM) is beneficial for both tailored part geometry and customized material design. With laser-based AM the copper-steel interface is highly prone to cracking. This study investigates a strategy of laser coating AISI H11 tool steel for a composite material consisting of AISI H11 tool steel and copper (H11/Cu) without using Ni-based interlayers. As an austenite stabilizing element, Ni dilution in H11 could lead to soft retained austenite, impeding wear resistance. The approach in this work employed presintering of tool steel powder to generate a porous H11 preform. Laser-based Directed Energy Deposition (DED-LB/M) was used for coating H11 tool steel on the porous H11 preform followed by copper infiltration of the preform. Investigation of the effects of the main processing parameters laser power, feed rate and powder mass flow on the weld track geometry clearly revealed different mechanisms when coating the porous preform compared to conventional substrate. Defects at the coating/substrate interface such as cold crack formation were successfully avoided by adjusting the process parameters and process sequence. The developed processing strategy may in the future combine Material Extrusion of metals (MEX/M) and DED-LB/M to allow for intricate preform geometries and to generate H11 coatings on H11/Cu respectively.

Contributing Authors

  • Johannes Vetter
    Institute of Photonic Technologies (LPT) | Erlangen Graduate School in Advanced Optical Technologies (SAOT)
  • Oliver Hentschel
    Institute of Photonic Technologies (LPT) | Erlangen Graduate School in Advanced Optical Technologies (SAOT)
  • Lova Chechik
    Institute of Photonic Technologies (LPT) | Erlangen Graduate School in Advanced Optical Technologies (SAOT)
  • Michael Schmidt
    Institute of Photonic Technologies (LPT) | Erlangen Graduate School in Advanced Optical Technologies (SAOT)
Johannes Vetter
Institute of Photonic Technologies (LPT) | Erlangen Graduate School in Advanced Optical Technologies (SAOT)
Track: Laser Additive Manufacturing
Session: DED Material
Day of Week: Monday
Date/Time:
Location: Mt. Olympus

Keywords

  • Copper Infiltration
  • H11/Cu Composite Material
  • Laser Coating
  • Laser-Based Directed Energy Deposition
  • Porous Substrate