Ceramic materials are used where other materials fail or at least do not meet the existing requirements to a comparable extent. The main advantages of ceramics are their outstanding thermal, chemical and mechanical properties. In addition, ceramics generally have a significantly lower density than metals and thus enormous potential for lightweight construction.
However, ceramics have not yet been widely used because, in addition to their low ductility, complex mechanical processing using conventional methods (e.g. milling and turning) is a major challenge. In addition, the integration of different functions into one component is only possible to a limited extent. Additive manufacturing (AM) technologies act as a game changer here. Geometrically highly complex ceramic components with previously unattainable functionality can now be manufactured. The need for post-processing, e.g. for machining, can be reduced significantly or is even completely unnecessary.

To increase the functionality of the components further different materials  with different properties are hybridized in one AM component. Possible combinations of properties that can thus be realized in a component are the following:
-    Electrically or thermally conductive & insulating,
-    magnetic & non-magnetic,
-    dense & porous, or
-    different optical properties (e.g. colours or transparency).

Within our contribution we want to focus on the combination of dense and porous areas in a ceramic component. On the one hand, we want to present the various possibilities that now exist in the field of AM to specifically generate pores and cavities in various sizes (nano to millimeter range) within ceramic components. On the other hand, we will present various AM technologies that make it possible to realize specific porosity gradients within AM components.