Effect of laser remelting on surface roughness and microstructure of AlSi10Mg selective laser melting manufactured parts

Selective laser melting (SLM) allows to obtain components by a careful selection of process parameters. This technology is becoming more and more attractive because it is capable of producing dense and complex metallic parts. Considering that one of the main drawbacks of this technology is the high surface roughness, this research aims at reducing it by means of skin laser remelting performed during the fabrication process. Since the remelting strategy affects only the external skin, the building time is slightly affected by this additional operation and the infill part properties remain unchanged. In this work, the effect of process parameters on the surface morphology and alloy microstructure has been analyzed. The obtained results highlighted that the remelting process allows to improve the surface morphology but it affects the subsurface defect formation. The obtainable surface roughness for different surface slopes was modelled as a function of the process parameters.