Selective laser sintering of multi-component Cu-based alloy for creating three-dimensional metal parts

Selective laser sintering (SLS) of a multi-component Cu-based alloy, which consisted of a mixture of Cu, CuSn, and CuP powder, was successfully processed. The XRD, SEM, and EDX analysis shows that the bonding mechanism of this process is liquid phase sintering with partial melting of the powder occurred. The CuSn powder with lower melting point acts as the binder, while the Cu powder with higher melting point acts as the structural metal. The element phosphorus acts as a fluxing agent to prevent the Cu particles form oxidation. The distribution of phosphorus shows higher concentration at grain boundaries due to low solubility of P in Cu. A case study on SLS of this powder system to fabricate a gear was carried out. The relative density of 82% and radial dimension error of 1.9% were achieved.