Characterization of Metal-Filled Resin for Stereolithography

The objective of this work is the characterization of a UV-curable metal-filled resin suitable for the production of metal components with an additive manufacturing process based on stereolithography. The major focus is given to the integration of an aluminium alloy powder into an acrylic resin curable through irradiation of light with wavelength equal to 405 nm. Different powders are considered and their effects on suspension stability and curing kinetics are analyzed with rheology and photo-rheology tests. Air trapping phenomenon have been investigated and reduced with a vacuum mixer and some defoamer have been tested. The suspension stability and the resin viscosity have been adjusted by balancing the base resin composition and with the integration of proper rheological additives. After the stabilization of the suspension, the printing parameters for the filled resin have been determined experimentally and some green parts have been produced and analyzed at the microscope. Considerations about debinding and sintering steps are made. The metal powder filled resin resulted to be a viable path for the production of green parts with stereolithography and a good opportunity for the development of an alternative AM technology for metal components.