Influence of Powder Oxygen Level and Particle Size on the Properties of Copper Binder Jetting Parts

Copper has a huge application area thanks to its high conductivity; however, it is difficult to print additively manufactured parts with powder bed fusion methods due to its high reflectivity and thermal conductivity. Binder jetting method has a high potential for use to eliminate these drawbacks. In this study, the effects of particle size distribution and oxygen level of the copper powders on physical, and mechanical properties were investigated. It is seen that 1070°C temperature and 100% H2 atmosphereare highly required. According to Archimedes tests, lower oxygen content (LO) 10-63 powder resulted in higher density compared to LO 15-45 powder. However, image analysis show that 15-45 μm powder yields better densification, and smaller internal porosities. In higher oxygen (HO) 15-45samples, there is inhomogeneity of pore distribution along the cross section. Consequently, LO 15-45 µm powder yields better tensile properties than HO powder.