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Novel carbon nanotube reinforced polymer derived ceramics by FAST sintering processing Niko Mantzel1, Stefan Rannabauer1, Ethel C. Bucharsky2, Karl G. Schell2, Michael J. Hoffmann2, Michael Scheffler1* 1 Otto-von-Guericke University Magdeburg, Institute of Materials and Joining Technology D-39106 Magdeburg, Germany 2 Karlsruhe Institute of Technology (KIT), Institute for Applied Materials – Ceramics in Mechanical Engineering D-76131, Karlsruhe, Germany ABSTRACT CNT (carbon nanotube) reinforced composite ceramics are supposed to show excellent mechanical properties. CNTs embedded in a ceramic matrix represent a high density of high modulus fibers in a matrix material which may result in high bending strength, high hardness and high fracture toughness. However, problems have been addressed in handling, compounding into a matrix and at least of the price of CNTs. Another disadvantage is the liberation of CNTs into the atmosphere during processing. A possible way to avoid some of these problems is the in situ generation of CNTs within a ceramic matrix. During the pyrolysis of preceramic polymers hydrocarbons are generated, and the presence of a suitable catalyst in the matrix may be used to convert the evolving hydrocarbons into CNTs. This was shown for a polysilsesquioxane resulting in a composite material composed of a polymer derived ceramic (PDC) matrix with CNTs in open pores or cracks formed during pyrolysis. After milling this composite material, sintering by a field assisted sintering technology (FAST) was shown to result in a CNT reinforced PDC material. In a very first attempt a series of CNT-PDC composites were manufactured resulting in ceramic bodies with a Weibull modulus of about 17 and a corresponding strength of 109 MPa as measured by a ball-on-3-balls test. The porosity was 10 % and the (micro) hardness exceeded 1400 HV 0.4/5. For comparison, a reference samples without catalyst and thus without CNTs resulted in a higher porosity and a corresponding strength of only 89 MPa. This new combination of the PDC route with in situ CNT formation and FAST processing might be a possible route to manufacture dense PDCs with tailored properties in the SiOC system. Keywords: polymer derived Ceramics, carbon nanotubes, FAST sintering Please underline: Oral or Poster presentation