TiO2 and [TiO2/β-SiC] microtubes prepared from an original process

Synthesis and Characterization of Alumina Microtubes in a Template Process from Short Carbon Fibers

“…Below 1000°C, no alpha alumina is observed, and the broad peaks of delta and gamma alumina suggest nanocrystalinity of those phases. This is in agreement with already published SEM investigations on coated carbon fibers, [2] where Al 4 (material T5), the gamma and delta phases are already transformed into denser alpha phase. Also, a shrinkage (densification) of product alumina is observable, which makes an additional evidence of alpha alumina existance in product tubes.…”

“…[4] The known possible applications of ceramic hollow fibers or microtubes include fuel cell research/oxygen permeation membranes, [5] nanocrystalline hydroxyapatite biocompatible biodegradable hollow fiber for biomedical application, [6] as well as TiO 2 photocatalyst microtubes. [7] Commercially available alumina short fibers, such as Saffil ® , are being investigated in metal matrix composites of aluminum, copper, magnesium, silver and various alloys for structural applications.…”

The synthesis of SiC and TiC protective coatings for carbon fibers by the reactive replica process

“…SiC materials with various textures (tubule, macroporous materials) as well as TiC coatings can be obtained by this way. [17][18][19] The sol-gel process has also been used to obtain other carbides like TiC or ZrC. 4,19,20 Another important advantage is that compared to the classical carboreduction by Acheson process, the sol-gel method makes it possible to synthesize carbide at lower temperature.…”

“…[17][18][19] The sol-gel process has also been used to obtain other carbides like TiC or ZrC. 4,19,20 Another important advantage is that compared to the classical carboreduction by Acheson process, the sol-gel method makes it possible to synthesize carbide at lower temperature. 21 In most cases, the overall reaction between the carbon and the oxide (carboreduction) reaction can be written as follows:…”

“…Finally, a carbon material coated with a mixed SiC-TiC layer is obtained in which the crystallization of rutile particles is minimized. 19,24 The low temperature oxidation of such a mixed SiC-TiC layer should result in a mixture of components SiC-TiO 2 which could be a good protection against oxidation of carbon fibers.…”