Study on fabrication of precise casting ceramic shell by DLP light curing 3D printing

For the fabrication of precise casting ceramic shell directly by 3D printing technology, the effects of exposure time and thickness of each layer on the dimensional accuracy of the ceramic printing parts were studied by self-made DLP light curing 3D printing equipment. The shrinkage of the parts after degreasing and sintering was measured and analyzed. The microstructure of the fracture was observed and analyzed by scanning electron microscope. The influence of the layout of the shell and the support design of the printed part on the quality of the shell after degreasing and sintering was also studied. The results show that the suitable each layer exposure time is 30~35 s and the layer thickness is 0.1~0.2 mm for this self-made equipment and the used ceramic slurry. The size shrinkage rate of sintered parts in each direction is about 15%, and the ceramic parts have some pore.When the printing shells have the support with a closed face shape and the green body are degreased and sintered in a vertical layout, the sintered shell are of good quality.