Mechanical and electrical properties of selective laser-melted parts produced from surface-oxidized copper powder

Abstract

Selective laser melting of pure copper is challenging because of its high optical reflectivity and thermal conductivity. Accordingly, the surface of pure copper powder was modified by oxidation to enhance the optical absorption. The powder with improved optical absorption facilitated the production of crack-free and dense copper parts at relatively lower laser energy density in both argon and nitrogen atmosphere. The microstructural analysis demonstrated the presence of stable melt tracks without obvious porosity. A very high electrical conductivity of approximately 89% of the international annealed copper standard, the hardness of approximately 93 HV, a tensile strength of approximately 270 MPa, and ductility of approximately 28% were achieved in the as-built condition.