Ceramic Print Head
This would possibly be a variant of the Syringe Based Extruder design, but perhaps not. Extruding ceramics would be a very interesting development because ceramics have some very nice characteristics that make them an ancient yet very useful material. Ceramics are able to withstand quite high temperatures and could be used to make some pretty extreme things.
-- Main.ZachSmith - 11 Feb 2007
Augmented Ceramic Extrusion
Others have used compressed air cylinders to force ceramic material through tubes to act as a printhead, however, a better approach may be to use a compressed cylinder such as a 2 liter bottle holding the ceramic material in unison with a peristaltic pump to better act as a flow regulator, allowing material to be deposited with precision; instead or relying on the air pressure to force the ceramic through the tube. This would allow for precise deposition of material. The peristaltic pump would act as both a valve and and extruder. A printed peristatic pump could be used much like a Bowden extruder, mounted on the frame of a 3d printer to deliver precise deposits of material.
This may also require a pressure sensor to monitor the pressure in the cylinder and to activate/deactivate a pump to maintain an optimum pressure in the cylinder during the extrusion duration. Custom firmware or modifications to an existing firmware would be required to perform this. SJFW is a likely candidate. This approach is currently being investigated by PacManFan in his MultiRep design.
PacManFan - 1.8.2012
Another approach to printing ceramic objects involves laying down complete layers of dry powder, then squirting liquid binder only where you want the powder to stick to your object. Once all the layers are down, you have a box full of mostly loose powder, with the parts you printed hidden somewhere deep inside.