Lithographiebasierte Fertigung keramischer Bauteile

Abstract

In the framework of the FP7 project PHOCAM the involved partners develop equipment (BluePrinter) and materials for the additive manufacturing of ceramic structures based on photopolymerisation. The core element of the BluePrinter, a DLP projector, generates pictures using high performance LEDs as light source and a 1080p DMD (Digital Micromirror Device) with 1920x1080 pixels as dynamic mask. The used pixel size of 40 µm result in the build size dimensions of 76.8x43.2mm. The highly viscous slurry, consisting of a filled photosensitive resin system, is exposed from underneath trough the transparent vat. Due to the illumination a thin layer of the slurry solidifies (polymerizes) locally. Thus, a green body is generated layer by layer with a standard layer thickness of 25 to 50µm. The following sintering process turns the green bodies into the final ceramic parts. In our investigation mainly an aluminium oxide powder is used as ceramic component. So far slurries with a solid loading up to 50vol% could be successfully processed with the developed system. The sintered ceramic parts achieve densities of 99,6%.