The research focuses on alloy design, powder production, and laser powder bed fusion (LPBF) of copper alloys. Copper and its alloys play a fundamental role for modern industrial applications due to their excellent thermal and electric conductivity in conjunction with considerable mechanical strength, for example, as welding electrodes and nozzles. By precipitation hardening, the hardness of low-alloyed copper, like CuCr1Zr, can be increased significantly. A combination of the geometry freedom of additive manufacturing with a tailor-made alloy design during powder production offers the opportunity to develop new alloy systems with a focus on the respective application. Experimental results regarding gas atomization, LPBF, property investigations, and property optimization of CuCr1Zr are presented. Powder particles and LPBF parts were analyzed with respect to phase and precipitate formation and compared to benchmark experiments of conventionally cast copper alloys. The microstructure differs significantly. Furthermore, the relative density of the LPBF parts reaches a value of 99.8%.
Due to the inhibiting behavior of Cu, NiCu alloys represent an interesting candidate in carburizing atmospheres. However, manufacturing by conventional casting is limited. It is important to know whether the corrosion behavior of conventionally and additively manufactured parts differ. Samples of binary NiCu alloys and Monel Alloy 400 were generated by laser powder bed fusion (LPBF) and exposed to a carburizing atmosphere (20 vol% CO–20% H2–1% H2O–8% CO2–51% Ar) at 620 °C and 18 bar for 960 h. Powders and printed samples were investigated using several analytic techniques such as EPMA, SEM, and roughness measurement. Grinding of the material after building (P1200 grit surface finish) generally reduced the metal dusting attack. Comparing the different compositions, a much lower attack was found in the case of the binary model alloys, whereas the technical Monel Alloy 400 showed a four orders of magnitude higher mass loss during exposure despite its Cu content of more than 30 wt%.