Process development for green laser LPBF of pure Cu using dimensionless numbers

Schäfle MB, Gärtner J, Nahr F, Bruder E, Schmidt M, Kirchner E (2025)

Publication Type: Journal article

Publication year: 2025

Journal

Progress in Additive Manufacturing Springer International Publishing

Abstract

The additive manufacturing of copper with conventional LPBF systems is challenging due to the high reflectivity of copper for wavelengths of standard infrared lasers and other characteristic properties like the high thermal conductivity. Green laser systems with a wavelength of 532nm pose an opportunity to reduce the necessary power of the laser systems and the number of defects while increasing the relative density. This study presents the results of a process development for a 532nm laser system for the LPBF process. Dimensionless indicators are used to analytically describe the probability of lack-of-fusion defects and investigate process parameters to achieve dense parts. The produced specimens are analyzed regarding their relative density as well as their hardness, tensile properties and electrical conductivity. It is found that dimensionless process indicators are generally suitable for an analytical approach in process development, but the adaptation to different processes results in the need for adjustment. A lower variation is found for the used dimensionless number compared to the volumetric energy density. The produced parts show a relative density of up to 99.5 % or more and mechanical and electrical properties, which are comparable to conventionally manufactured copper. A high relative density is achieved with a laser power of 192W, a laser scan speed of 400 mm/s and a hatch distance of 50μm.

Authors with CRIS profile

Florian Nahr Lehrstuhl für Photonische Technologien (LPT) Michael Schmidt Lehrstuhl für Photonische Technologien (LPT)

Involved external institutions

Technische Universität Darmstadt

Germany (DE)

How to cite

APA:

Schäfle, M.B., Gärtner, J., Nahr, F., Bruder, E., Schmidt, M., & Kirchner, E. (2025). Process development for green laser LPBF of pure Cu using dimensionless numbers. Progress in Additive Manufacturing. https://doi.org/10.1007/s40964-025-01105-5

MLA:

Schäfle, Moritz Benedikt, et al. "Process development for green laser LPBF of pure Cu using dimensionless numbers." Progress in Additive Manufacturing (2025).

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