Investigation of Droplet Deposition for Suspensions Usable for Thermoplastic 3D Printing (T3DP)

Thermoplastic 3D printing (T3DP) is an additive manufacturing (AM) technology, which can be used for the production of dense single- and especially multi-material components. This becomes possible because of the combination of the precise deposition of small droplets of molten thermoplastic suspensions containing ceramic or metal particles, and a curing mechanism caused on cool down increasing the viscosity. In this paper, the droplet formation behavior of zirconia suspensions for T3DP (82 and 84 wt.%) was investigated. The droplet fusion factor (dff) is introduced to calculate the necessary distance between two droplets to form filament-like structures by fusion of adjacent droplets. Filament-like structures with a smooth surface and a nearly homogeneous cross section were manufactured for both suspensions with a dff of 44% or higher.