Powder bed binder jetting additive manufacturing of silicone structures

Abstract

The feasibility of a hybrid additive manufacturing (AM) method combining material extrusion and powder bed binder jetting (PBBJ) techniques for fabrication of structures made of silicone (polysiloxane) is investigated in this paper. A full factorial experimental design was conducted to maximize the geometrical accuracy of the parts. The rheological and morphological properties of the silicone powders, the thermal characteristics of the liquid silicone binder, and mechanical characterization the additively manufactured parts are reported. Using this hybrid AM method, porous cylindrical structures (5 mm diameter (D) × 3 mm height (H)) with potential applications in biomedical industry were additively manufactured. The final structures are composed of ∼60% silicone powder, ∼ 30% silicone binder, and <10% air voids. These three phases are distributed throughout the structure in a non-uniform fashion.