Conditions of Infiltration and Baking of 3D Printed Plaster Molds for Centrifugal Mixed-Powder Method

In this study, plaster molds fabricated by three-dimensional (3D) printing were used for the centrifugal casting of pure Al, which is a fundamental centrifugal mixed-powder method. The relationship among processing conditions, relative density and pore structures of centrifugally cast pure Al, and strength of molds were investigated. The relative density and pore structures of the Al casts were studied by the Archimedes method and X-ray computer tomography (CT) method. It was found that if the baking temperature of the mold can be increased using a genuine fixing agent and a genuine infiltrant Al casts having a density equivalent to that of the conventional mold can be produced. Although the strength of the mold can be increased by adding an Al(H₂PO₄)₃ infiltrant, the strength of the mold was also found to decrease when baking was carried out at 600 °C. When water was sprayed before baking, the strength of the mold could be improved. However, the part hardened by hydration condensation was found to be limited to the surface region.