Fused Filament Fabrication (FFF) for technical ceramics

As with any other 3D printing process, the first step is to generate a CAD file that represents the exact dimensions of the desired part. This CAD file is then broken down by software into horizontal layers (slices). The individual layers are simultaneously translated into X and Y motion commands for the nozzle head in the subsequent print. The resulting print script also determines the pattern and fill level with which the respective layers are to be printed. During the actual printing process, a filament on a roll is then pulled towards the nozzle. In front of the nozzle there is a so-called hot end in which the filament is melted. By further conveying and melting the filament, the material is finally pressed or extruded through the nozzle in the form of a strand. With the previously generated movement commands, a complete layer can be filled by selectively depositing the strand on the building platform. In order to print the next layer, the D-printer then moves upwards in the Z-direction at the height of the desired layer thickness. This is done either by raising the print head or lowering the building platform, depending on the design of the printer. Now the next layer can be applied to the previous one.

To ensure that the next layer adheres well and that the material already deposited does not solidify prematurely, the building platform is additionally heated. Once all layers have been printed, the component is finished. If a thermoplastic filament with a ceramic content is used, a debinding step follows in which the organic components are removed from the component, which could otherwise lead to undesirable deformations and cracks in the later component during sintering. It is only through the sintering process that the component then acquires its actual ceramic properties.