Novel carbon/ceramic hybrid fibers with improved oxidation resistance

15.11.2024

The development of new technologies requires materials with very unusual and customized properties. In the past, carbon and ceramic fibers have been developed for extreme conditions, but they have specific advantages and disadvantages in terms of oxidation stability and cost.

In recent years, the Chair of Ceramic Materials Engineering (CME) at the University of Bayreuth has been able to show that a hybrid polymer of silazanes and polyacrylonitrile leads to a carbon-rich material with homogeneously distributed ceramic nano-inclusions after pyrolysis, which has significantly improved oxidation stability compared to carbon fibers. Wet spinning of the hybrid polymer produced fibers with a diameter of 20 µm, high tensile strengths of 2.0 GPa and E-modulus of 175 GPa. Electrospinning of the hybrid polymer resulted in a novel multifibrillar C/SiCON fiber type with a diameter of approx. 20 µm, consisting of thousands of individual nano-fibers. The tensile strength of approx. 700 MPa can be significantly increased if the nanofibers are prevented from sticking together.