Influence of the Feedstock Preparation on the Properties of Highly Filled Alumina Green-Body and Sintered Parts Produced by Fused Deposition of Ceramic
Thomas Heim, Frank Kern
Abstract
This paper investigates new approaches for the blending and plastification of ceramic powder with a binder to form fused deposition of ceramic (FDC) feedstock. The fabrication of highly filled ceramic filaments was accomplished using the granulation by agitation technique, followed by twin-screw extruder homogenization and single-screw extruder filament extrusion. The feedstocks are based on alumina (Al2O3) powders, which were prepared with an industrial binder through three different routes: wet granulation, melt granulation and melt granulation with a suspension. After printing cubic samples and tensile test specimens on a commercial fused deposition modelling (FDM) printer, the properties of the resulting green-body and sintered parts were investigated. The green-body mechanical values are compared with results from commercially available filaments. Mixing the binder with the alumina powder and surfactant in a suspension produces the lowest viscosity and the best elongation at break.