Cold metal transfer-based wire arc additive manufacturing of pure copper with ultra high tensile strength

Abstract

Copper is used in various heating and cooling applications by exploiting its excellent thermal and electrical conductivities. Powder- and laser-based additive manufacturing (AM) of pure copper is challenging as it encounters porosity because of its low absorptivity. The present research reports the feasibility of cold metal transfer-based wire arc additive manufacturing (CMT-WAAM) for the manufacturing of pure copper thin wall. The microstructure of the deposit is examined at three distinct locations. The mechanical properties (including ultimate tensile strength, yield strength, elongation and hardness) are examined in both scanning direction (SD) and build direction (BD). The thermal and electrical properties of the deposit are also measured. The deposited thin wall is reported to be firm and straight without any bulging and collapsing. The CMT-WAAM fabricated pure Cu samples exhibit superior tensile strength (310 ± 12 MPa in SD and 265 ± 9 in BD) than all other AM techniques. The thermal and electrical conductivities of the built copper wall are comparable to the previously reported conductivities of pure copper fabricated by other AM routes.