High productivity parameter development framework for laser powder bed fusion of copper

Copper is highly sought after for advanced manufacturing due to its exceptional electrical conductivity, thermal conductivity, and good corrosion resistance, making it ideal for applications ranging from heat exchangers and electric transportation to rocket engines. However, its widespread adoption in laser powder bed fusion (PBF-LB), a prominent additive manufacturing (AM) technique, is limited. This is primarily due to its inherently high reflectivity at infrared wavelengths (around 1070 nm), which is typically employed by industrial PBF-LB systems. The high reflectivity of copper, combined with its high thermal conductivity, leads to multiple issues, including balling, porosity, spatter, and damage to laser optics. Additionally, copper is typically printed on stainless steel LPBF build plates, which leads to additional challenges for support structure parameter development.
In this work, physics-based process maps that are material-agnostic and machine-agnostic are used to develop a framework that can help practitioners rapidly develop parameters for industrial components printed with copper or its alloys. This framework is implemented on commercially pure copper (C101) for two different powder types (MPW’s non-equiaxed powder and gas-atomized near-spherical powder) at a higher productivity layer thickness (60 µm). The PBF-LB print outcomes are analyzed and compared in detail using in situ optical tomography, optical microscopy, X-ray computed tomography, surface profilometry, and IACS electrical conductivity testing. The best parameters from this study enable parts with a density of over 99.50%, low roughness, and high electrical conductivity. This work provides insights into the feasibility of the adoption of environmentally- and economically sustainable copper powders for PBF-LB AM.