Porosity, texture, and mechanical properties of pure copper fabricated by fine green laser powder bed fusion

Abstract

Previously, the additive manufacturing of pure copper was carried out using a large-spot (0.2 mm) infrared or green laser. In this study, the laser powder bed fusion (LPBF) of pure copper using a green laser with a 532 nm wavelength and a fine spot (40 μm) was investigated. After the optimization of the process parameters, pure copper blocks with a maximum density of 99.6 % were prepared. Using micro-CT, three porosity defects that affect the densification and tensile properties of pure copper were identified, namely lack-of-fusion, keyhole, and small-hole porosities. An obvious < 110 > texture in the build direction was observed in the fabricated pure copper blocks. Anisotropy of the mechanical properties was found and can be attributed to the interaction between the textures and porosities during the tensile process.