Processing of CuAg7Zr and CuCr1Zr via Laser Powder Bed Fusion and the effects of Oxidation on Reflectance

Copper-based alloys are characterized by high thermal and electrical conductivity and are therefore well suited for demanding industrial applications. However, their processing by laser powder bed fusion (LPBF) poses significant challenges due to their high reflectance at 1064nm and high thermal conductivity. This work focuses on the newly implemented laser powder bed fusion alloy CuAg7Zr, compared with the well-established CuCr1Zr. Suitable process parameters for CuAg7Zr and CuCr1Zr are first identified and their effect on the resulting porosity is analysed. As part of a comprehensive parameter study, laser power, scan speed, and hatch spacing are varied to determine stable process windows for producing dense components. Influences of optical reflectance on the energy uptake for melting of these alloys is investigated. The findings aim to show processing of CuAg7Zr with LPBF and differences in reflectance behaviour, powder condition and process parameters in comparison to CuCr1Zr, providing valuable insights for optimizing the LPBF process for copper-based alloys.