Properties of RU955 Si3N4 Filament for Fused Deposition ofCeramics

One ofthe key elements in the FDC process is the development of ceramic loaded fusible filament. The filament is not only material feed stock for deposition, but also serves as a piston to push the fused material through the FDC liquefier. Therefore, the FDC filament has to meet several requirements. It should have enough flexibility to satisfy the automatic feeding requirements, enough stiffness to carry the force for extrusion in the liquefier, and a low viscosity. A series of binders developed at Rutgers University show promising properties and meet these requirements. However, the change of filament properties with time and storage conditions was observed, and they dramatically influenced the FDC process. Systematic experiments were carried out in order to understand filament aging and establish proper storage conditions. The results indicate that moisture in the environment plays an important role in the filament aging. Vacuum treatment at 30°C apparently accelerates the aging process. The mechanisms offilament aging and the method offilament evaluation will be discussed.Mechanical Engineerin