Gold plating of AlSi10Mg parts produced by a laser powder-bed fusion additive manufacturing technique

Abstract

Laser powder-bed fusion (LPBF) method is one of the most important additive manufacturing (AM) technologies. AM-LPBF parts frequently need post-printing coatings for electrical and thermal conductivity enhancement, or matching decoration considerations. The current study presents a methodology for surface finishing of AM-LPBF AlSi10Mg artifacts coated with electroless gold. For this purpose, gold was deposited on AM-LPBF AlSi10Mg disk-shaped specimens and coins, resulting in an appearance similar to the original objects. The gold coating was characterized as a function of deposition time and gold film thickness. Mass and dimension measurements, optical profilometry, light microscopy observation, XRD analysis and a FIB-SEM technique were applied to characterize the coated samples. The roughness of the plated specimens was slightly reduced as the thickness of the gold film was increased. AM-LPBF AlSi10Mg disk-shaped specimens were coated successfully for the first time by electroless gold plating technique. The developed surface finish technique can be used for various applications, including 3D-printed replicas of ancient prestige artifacts and coins for museum exhibitions.