SiC-Based Ceramic Fibers Prepared via Organic-to-Inorganic Conversion Process-A Review

Abstract

Review péÉÅá~ä fëëìÉ Äó dìÉëí bÇáíçêëW lêÖ~åáÅ-íç-fåçêÖ~åáÅ`çåîÉêëáçå mêçÅÉëë Ñçê mçäóãÉê-aÉêáîÉÇ`Éê~ãáÅë pá`_~ëÉÇ`Éê~ãáÅ cáÄÉêë mêÉé~êÉÇ îá~lêÖ~åáÅíçfåçêÖ~åáÅ çåîÉêëáçå mêçÅÉëë-^oÉîáÉï ሱᑿ-ᠪᑿং၁ɟɵɃɁǺȗȚ SiC ṾɃɱɧɋȷέỺǽ۰༔ ἕ◻Several types of Si-based ceramic fibers have been prepared using an organic-to-inorganic conversion process. In this article, the preparation, microstructure, and high-temperature stability of SiC-based ceramic fibers prepared from polycarbosilane of an organosilicon polymer are reviewed. The first fiber produced was an amorphous Si-C-O fiber, next was a low-oxygen content Si-C fiber, and finally, a nearly stoichiometric SiC fiber was developed. These fibers are continuous fine fibers that have high tensile strength with high heat resistance. The pyrolytic behavior and active-passive oxidation of these fibers at high temperatures are described here. The heat resistance of these fibers increases in the order of the Si-C-O fiber, the Si-C fiber, and the SiC fiber. The hightemperature properties are dependent on the atomic arrangement and the quantity of amorphous SiC x O y and glassy carbon in the fibers. Possible applications for these fibers are as refractory materials, and as reinforcement fibers for plastics, metals, and ceramics.

Ceramic microparticles and capsules via microfluidic processing of a preceramic polymer

“…Therefore, they can be subjected to a large variety of different forming methods, some of them unique or at least much more easily exploitable for polymers than ceramic powders or pastes. These include casting (Melcher et al 2003), infiltration (Satoa et al 1999), pressing (Galusek et al 2007), injection moulding (Walter et al 1996), extrusion (Eom & Kim 2007;Eom et al 2008), machining (Rocha et al 2005), fibre drawing (Okamura et al 2006), blowing/ foaming (Colombo 2008), ink jetting (Mott & Evans 2001), rapid prototyping (Friedel et al 2005), electrohydrodynamic spraying/spinning ), aerosol spraying (Bahloul-Hourlier et al 2001, self-assembly (Malenfant et al 2007) and microcomponent processing such as UV/X-ray lithography, nano/micro-casting, replication, micro-extrusion and embossing/forging (Schulz 2009). …”

Wet Oxidation Behavior of Near-Stoichiometric SiC Fibres in the Simulated Aeroengine Circumstance

“…The KD-S SiC fibres used in this study were produced by our laboratory using the procedure of Yajima [2,5]. These nearstoichiometric SiC fibres were obtained by adding hydrogen to eliminate excess carbon during sintering process.…”

“…Silicon carbide materials could be oxidized in the passive/active oxidation regime, which is influenced by the purity and microstructure of materials, as well as the temperature and oxygen partial pressure [2]. Previous studies have confirmed that SiC fibres with low oxygen content would be passively oxidized in both wet air and dry air [12].…”

“…The continuous silicon carbide reinforced ceramic-matrix composites (SiC f -CMCs) have been widely used in military equipment and aircraft components such as combustor liners and turbine vanes [1,2]. Although a protective silica layer could be generated during passive oxidation, the oxidation resistance of SiC fibres still needs to be improved.…”

Processing of polymer-derived porous SiC body using allylhydridopolycarbosilane (AHPCS) and PMMA microbeads

“…For making a bulk body, suppressing critical crack formation during pyrolysis is a prerequisite even if minor ones could be admissible. By taking into account the fact that a polymeric preform of high specific surface such as fibers 18), 19) and particles 20), 21) can be well consolidated into an almost crackfree pyrolyzed product, it is expected that high specific surface and simple and continuous geometry contribute to reducing crack initiation. Those could work well for sound consolidation through shortening gas elimination pathway and unifying thermal shrinkage distribution.…”