3D Nanocomposites of Covalently Interconnected Multiwalled Carbon Nanotubes with SiC with Enhanced Thermal and Electrical Properties

Abstract

); and also a semiconducting behavior with an electron hopping mechanism associated to a 3D variable range hopping model. These fi ndings demonstrate that it is indeed possible to fabricate SiC-CNT composites with enhanced physical properties that can be used as multifunctional materials.

Light and Strong Hierarchical Porous SiC Foam for Efficient Electromagnetic Interference Shielding and Thermal Insulation at Elevated Temperatures

“…The continuous carbon thermal process from outside to inner resulted in covalently bonded SiC structure. 43,44 As a consequence, the struts of the macropore walls in hierarchical porous SiC foam could endure higher stresses without breakage.…”

Flexible Fe3Si/SiC ultrathin hybrid fiber mats with designable microwave absorption performance

“…4(a). The diffraction peaks of b-SiC (JCPDS#74-2307; 35.6 , 60.0 and 71.8 ) 21 are observed in all the patterns, which become much sharper as the Fe 3 Si content increased from 0 to 6.5 wt%, implying that the crystalline size are getting larger. Actually, the adding of Fe(acac) 3 in the PCS solution can promote the formation of SiC phase, which is attributed to the Fe element acting as the catalyst when SiC crystal was formed from PCS precursor.…”

“…Therefore, defects 18,19 or second phase additions (e.g. nanocarbon phase, [20][21][22][23][24] ZnO nano-crystals, 25 Al doping 26 ) are usually introduced to enhance the permittivity of 1D SiC nanomaterials, achieving a proper impedance match degree for microwave absorption properties. In particular, magnetic phase doped 1D SiC nano-materials, such as Fe-SiC whisker, 19 Fe 3 O 4 -SiC hybrid nanowires, 27 and Co-SiC hybrid nanowires, 28 could effectively improve the EM absorption performance by introducing both dielectric and magnetic losses.…”

Anisotropic compressive properties of porous CNT/SiC composites produced by direct matrix infiltration of CNT aerogel

“…10 Therefore, it is usually utilized in various aeronautical and aerospace applications. In the last decade, reinforcement of SiC matrix with CNT has been suggested for improvement of the mechanical properties, [11][12][13][14][15] electrical transport potential, [16][17][18][19] thermal conductivity, 17 and microwave absorption 20,21 performances of SiC.…”

“…CNT agglomerates, forming spontaneously unless otherwise controlled, are undesirable since they can act as internal defects causing stress concentration and crack initiation, hence hampering the beneficial reinforcement effect offered by the tubes. Current CNT/SiC composite fabrication methods include (i) disperse-mixsintering, 11,12,16,17,[22][23][24][25][26][27][28][29][30] (ii) chemical vapor infiltration (CVI) of arrays, 13,14,31,32 (iii) precursor infiltration pyrolysis of polymer precursor/CNT mixtures, 15,19,33,34 (iv) in situ grown of CNTs on SiC powders or porous SiC ceramics, 18,20,35 (v) deposition or synthesis of SiC on CNTs, 28,36,37 and others. 38 Compared with other ceramic processing methods, the CVI method possesses several significant advantages including near-net final shapes, minimization of the mechanical damage of the tubes due to much lower pressures and temperatures in the range of 900°C-1100°C, low mechanical stress, higher purity of the matrix.…”