Electrical, dielectric and microwave-absorption properties of polymer derived SiC ceramics in X band

High-temperature dielectric and electromagnetic interference shielding properties of SiCf/SiC composites using Ti3SiC2 as inert filler

“…On the other hand, quantities of interfaces are formed between the Ti 3 SiC 2 particles and SiC matrix with the incorporation of Ti 3 SiC 2 filler. The main contribution of the matrix may include the grain boundaries among these SiC nanocrystals, the grain boundaries between SiC nanocrystals and excess carbon, and the interfaces between Ti 3 SiC 2 particles and SiC matrix [20,34]. These free electrons gathered in the interfaces can form space charge layers and give rise to the space charge polarization and relaxation under …”

“…Thus, the presence of large surface areas or interfaces is beneficial to this mechanism. Based on the previous studies [20,21], it has been identified that there exist amounts of excess carbon and b-SiC microcrystals including many dangling bonds and vacancies defects in the fibers and matrix of SiC f /SiC composites fabricated by precursor infiltration and pyrolysis (PIP) process, which contributes to enhancing the electrical and dielectric properties of the composites. Several papers have investigated the EMI shielding effectiveness (SE) of SiC f /SiC composites at ambient temperature.…”

Temperature-dependent dielectric and microwave absorption properties of SiC /SiC–Al2O3 composites modified by thermal cross-linking procedure

“…The carbon materials, including the carbon black, carbon fibers, and carbon nanotubes, are of great susceptibility to oxidation above 400 • C, which restricts their wide applications at high temperatures [11]. SiC is an important semiconductor with high strength, low density, excellent electrical and oxidation resistance properties, which is expected to be used under harsh environments of high temperature and high frequency [12,13]. It has been recognized that the continuous SiC fiber-reinforced SiC matrix (SiC f /SiC) composites possess significant advantages compared with the monolithic SiC materials by integrating the optimal structural and functional performances at high temperatures [14].…”

Improvement of mechanical and dielectric properties of PIP-SiCf/SiC composites by using Ti3SiC2 as inert filler

“…6. As the previous study manifests that the PIP-SiC is incompletely crystalline and remains excess carbon [29,30], the pyrolyzedSiC/paraffin composites show low ε 0 (4-6) and ε″ (2-2.5) values. And the complex permittivity of as-received Ti 3 SiC 2 varies from 9-i0.5 to 11.5-i3.1.…”