Fine grained functional ceramics or metal/ ceramic or graphite/metal/ceramic composites are established materials in energy conversion or energy storage devices. In H2-metallurgical processes, H2-burner systems or NH3-conversion devices high alumina containing ceramics will play a key role a) due to their chemical resistance in H2 reducing atmospheres containing also water steam as well as b) due to their creep resistance at elevated temperatures. Unfortunately high alumina ceramics also in their coarse grained structures as refractories suffer under thermal shock conditions. “Refractory Composites” based on coarse grained refractory ceramics and refractory metals such as Nb or Ta or carbon achieve not only improved thermal shock-performance accompanied by excellent creep-resistance, their property spectrum is expanded via additional properties, such as electric and thermal conductivity. “Sandwich components” based on alumina shell and core materials based on electrical conductive refractory composite materials or carbon will be demonstrated for possible applications in the metallurgy and in energy plants.
 
Another approach to meet the demands of fine grained thermal shock resistant high alumina functional products such as nozzles or filters for metal melt filtration is based on the 3D lightweight manufacturing. Application of Fused Filament Fabrication technique allows to manufacture thin-walled fine grained refractories with pre-defined hollow inner structure and dense fine-grained layered outer structure at the same time. The dense fine-grained layer by layer outer structure on one hand contributes to high corrosion and infiltration resistance, which is indispensable for industrial metallurgical applications; on the other hand, due to the thin-walled layer by layer structure with fine pores as well as the  lightweight geometry of the ceramic component (macro-cavities in between inner and outer structure) lead to sufficient decrease of the crack propagation energy. In addition with the aid of FFF micro-pores can be positioned were it is required.
 
MgO-C recycling and upcycling approaches are also very interesting to meet CO2-challenges. MgO-C materials will still continue to be the critical slag resistant materials in metallurgical devices such as converters, E-furnaces etc. 2.5 kg MgO-C material are consumed for each produced t of steel. MgO-C recycling materials do not only contribute to a decrease of 1.3 up to 1.7 t CO2 for each t of produced dead burned magnesia (DBM), a combination with steel powders can lead to interesting anode materials. In this kind of upcycling approach low carbon or carbon free metal/ceramic coarse grained composite materials as anode functional components can be provided for the aluminum fused-salt electrolysis.
 
Last but not least the combination of electrical conductive heating composite materials with microwave plasma burners and/or H2-burners could be important steps to fulfill the demands for the future CO2-challenges in sintering and melting technologies of inorganic materials as well as in future gas turbine concepts.