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Thermal Stability of Polycarbosilane‐Derived Silicon Carbide Fibers under Reduced Pressures

“…7,13,14 Figure 4 shows that, for Nicalon and Hi-Nicalon S fibers that have been exposed under a reduced pressure of 1.3 Pa, the opposite result-i.e., a significant increase in -is observed. The active oxidation produced vigorous gas generation and made the fiber structure porous.…”

Oxidation of Low‐Oxygen Silicon Carbide Fibers (Hi‐Nicalon) in Carbon Dioxide

“…Therefore, the studies of oxidation kinetics, microstructural, and mechanical changes have been extensively conducted for the fibers exposed in oxidizing environments such as air, O 2 gas, and a H 2 -H 2 O gas mixture. [1][2][3][4][5][6][7][8][9][10][11][12][13] Researchers have also investigated the oxidation of the fibers in a wide range of oxygen partial pressures of Ar-O 2 gas mixtures, resulting in determination of the oxidation mechanism, the suppression effect of SiO 2 film on the thermal decomposition of SiC fibers, and the active-to-passive transition for the oxidation of the fibers, etc. 14 -22 High-temperature application of SiC fibers to the hot section components of gas turbines, piston engines, and heat exchanger tubes involves exposure to combustion environments.…”

SiC fibers with controllable thickness of carbon layer prepared directly by preceramic polymer pyrolysis routes

“…Compared with the CVD, PVD and ED technologies, this preceramic pyrolysis route seems relatively simple and convenient. Considerable works have reported this carbon layer forms during the pyrolysis process [22][23][24]. However, efforts to prepare the SiC fibers with controllable carbon layer directly by preceramic pyrolysis routes are scanty in the literature.…”