Raw materials and processes were developed to manufacture a porcelain figure using a binder jetting 3D printer. A digital sketch was created by considering the structural stability, and the optimal geometry and thickness (< 20 mm) were determined through thermal flow analysis. Dry glass beads, clay, and quartz were mixed in 34%, 46%, and 20% proportions, respectively. Alumina cement (5%) and sodium silicate powder (4%) were added to facilitate the curing process. The optimal particle size of the glass beads was found to be 86 μm from measurements of the angle of repose, and the flowability was further enhanced by adding 3% hydrophilic fumed silicas, whose specific surface area was 90 m2/g. Although the addition of hydrophobic fumed silicas caused a significant change in flowability, this material was not used in the experiment because of its incompatibility with the aqueous binder. Using bar-type sample sintering and glaze applicability measurements, we determined the optimal conditions for the glazing and heat treatment processes: the first sintering step was conducted at 1100 oC, followed by the second sintering at 1200 oC by applying a glaze with 50% solid content. The geometry match between the final porcelain figure and the digital sketch was up to 67% accurate when the surface texture was included, and up to 92% when only the skeletons were compared.

Keywords: Raw materials, Porcelain, Binder Jetting, Flowability, Contact angle.