Ceramic fibres

Chemistry, structure and processability of boron-modified polysilazanes as tailored precursors of ceramic fibers

“…Processing of Si-based ceramic fibers including SiC, Si 3 N 4 , silico carbonitride (Si/C/N) and silicoboron carbonitride (Si/B/C/ N) derived from preceramic polymers such as polycarbosilanes (PCSs), polysilazanes, polycarbosilazanes and boron-modified polysilazanes or polyborosilazanes [30][31][32][33][34][35][36][37][38][39][40][41][42] is still an extremely challenging topic in PDCs. They represent the best candidate to reinforce a ceramic matrix in the next generation of nuclear energy conversion power plants.…”

Alkoxide-based precursors for direct drawing of metal oxide micro- and nanofibres

“…Although this enables drawing of fibres as thin as 37 nm, the technology is demonstrated only for polymer fibres. In the case of ceramics, direct drawing of fibres has resulted in diameters of tens of microns [9]. It should be noted that anisotropic crystal growth alternatively enables bottom-up approach for preparation of metal oxide nanofibres and 1D structures [27][28][29].…”

“…The drawing of ceramic fibres had attracted great attention during the 1980 s [8,9] because it allowed producing temperature-resistant and mechanically stable textiles and fibrous materials. Metal oxides rather decompose upon heating than transform into viscous melts, and therefore the key to the preparation of metal oxide fibres is finding suitable precursors.…”

Oxide Fibers

“…It has been known since the 1950s that single crystal filaments, of oxides and other materials, with micron size diameters can be grown (18). These filaments, which are known as whiskers, possess very high strengths because of the lack of defects which otherwise weaken larger diameter fibers.…”

“…The fiber is circular in cross section and has a smooth surface. The fiber is obtained by the chemical conversion of a polymeric precursor fiber, made from a polyaluminoxane dissolved in an organic solvent to give a viscous product with an alkyl silicate added to provide silica (18). The precursor is then heated in air to 760…”