Indentation hardness

Selective laser melting

Metallurgy

Materials science

Coating

Ultimate tensile strength

Equiaxed crystals

Laser

Physics

Crystallite

Optics

Microstructure

Optical microscope

Composite material

Scanning electron microscope

Gas dynamic cold spray

Copper

Surface and Coatings Technology

To study effect of the different metal additive manufacturing techniques on microstructural evolution, phase constitution and the relationship between the microstructure and tensile behavior of pure Cu parts, components were manufactured by selective laser melting (SLM) technology and cold spraying (CS) technology, respectively. The microstructure of Cu parts was detected using an optical microscope (OM) and scanning electron microscopy (SEM). The XRD spectrum revealed that only Cu phase is formed in the SLM Cu and CS Cu samples. The microstructure of the SLM Cu samples is constituted by the polycrystalline grains with substructures including the columnar dendrites and the equiaxed structures. As for the CS Cu samples, only the equiaxed grains were detected. In terms of the main physical properties, the averaged electrical conductivity of SLM Cu sample is 41% IACS, while that of CS Cu sample is 73% IACS. For the microhardness, the mean microhardness value of the CS Cu and the SLM Cu samples is 144.2 ± 4.3 HV0.05 and 83.6 ± 5.2 HV0.05, respectively. With regard to the statistic mechanical properties, the yield strength (YS) and ultimate tensile strength (UTS) of the SLM Cu part is approximately 185.8 ± 6.1 MPa and 242.2 ± 8.2 MPa, respectively.

Pure copper components fabricated by cold spray (CS) and selective laser melting (SLM) technology