Abstract

A novel binder jetting process using a mixture of sodium silicate powders and water-based solvent as an inorganic binder system and the corresponding posttreatment process were developed to resolve a contradiction of increased strength with reduced gas volume of sand molds fabricated by traditional binder jetting processes using organic binder. Optimized processing parameters of 50 % binder saturation, 10 wt% sodium silicate powder addition, 0.2 mm layer thickness, 50 vol% infiltration concentration of alcohol – water solution, 5 min infiltration time, and 250 °C baking temperature buried in glass beads for 1 h were determined by the systematically investigation of printing process. The produced sand mold achieved an excellent performance with a tensile strength of 4.5 MPa and a maximum gas volume of 8.1 L/kg. A casting experiment was carried out to verify the performance of sand mold, the results showed that the casting fabricated using the sand mold prepared by the process studied in this paper has a better surface quality and fewer subcutaneous blowholes in comparison to the traditional process, indicating its excellent industrial application prospects.