Selective laser melting (SLM) of layered gold powder is a rapid manufacturing (RM) technology capable of turning a CAD model into a piece of jewelry without intermediate steps. As with any new technology, giving concrete and tangible form to concepts requires research and development and, as Strauss (Santa Fe Symposium 2009) points out, issues that can arise with RM jewelry regard powder quality and availability. This paper focuses on these issues together with laser power, laser scanning speed, and the thickness of the powder layer. A design of experiments (DOE) approach was used to characterize the influence of those variables on an 18K gold powder with reference to physical and chemical attributes, surface roughness, defects, and mechanical properties. A comparison of a series of specimens produced by SLM and lost-wax casting will be presented.

Authors: Damiano Zito, Silvano Bortolamei, Alessio Carlotto, Prof. Ilaria Cristofolini, Alessandro Loggi, Prof. Alberto Molinari