Selective laser melting (SLM) of pure copper using 515-nm green laser: from single track analysis to mechanical and electrical characterization

Laser powder bed fusion allows to manufacture new components with optimized geometry and lightweight materials. Many common materials are now available for this process like steel, aluminum, and titanium. Copper is more difficult to produce due to its low absorptivity at 1064-nm wavelength and high thermal conductivity. Recent evolutions in laser technology allowed to build a selective laser melting machine using 515-nm green laser. This wavelength is better absorbed by copper for manufacturing. The absorptivity spectrum shows an absorptivity nearly nine times higher for the green laser by pure copper compared to infrared laser. This paper will focus on the manufacturing of pure copper parts from single-track analysis to electrical and mechanical characterization of the material. Porosity level and roughness will also be studied. Based on these observations, green laser could permit to avoid oxidation or other powder treatments. This new laser technology opens a new way to produce materials with high thermal conductivity.