Temperature dependence of dielectric properties of SiCf/PyC/SiC composites

Song, Huihui; Zhou, Wancheng; Luo, Fa; Huang, Zhibin; Qing, Yuchang; Chen, Malin; Yang, Mei

doi:10.1016/j.mseb.2015.01.007

Cited by 25 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With increasing temperature, the real part of the permittivity is slightly reduced, while the imaginary part of the permittivity is enhanced, leading to an increasing dielectric loss (tand = e″/e 0 ) when temperature increases. On the basis of Debye's equations for the complex permittivity of a specific material, the real and imaginary parts can be described as 8,30 e 0 ¼ e 1 þ e s À e 1 1 þ ðxsÞ 2 (7) e 00 ¼ ðe s À e 1 Þxs…”

Section: Temperature-dependent Em Wave Absorbing Propertiesmentioning

confidence: 99%

“…By now, most of researches on dielectric CMCs focus on the target frequency range of X‐band (8.2‐12.4 GHz) and Ku‐band (12.4‐18 GHz). Current researches mostly focus on broadening the absorbing frequency range since the reflection loss (RL) of CMCs generally adopts a concave relationship with increasing frequency . Meanwhile, the absorbing properties of these materials would be impaired at high temperature due to permittivity changing with increasing temperature .…”

Section: Introductionmentioning

confidence: 99%

“…Current researches mostly focus on broadening the absorbing frequency range since the reflection loss (RL) of CMCs generally adopts a concave relationship with increasing frequency. [7][8][9][10][11][12] Meanwhile, the absorbing properties of these materials would be impaired at high temperature due to permittivity changing with increasing temperature. 7,8,10 Thus, the specific EM wave absorbing material adopting the convex RL function with increasing frequency, which would realize strong absorptions at both high and low frequency in [8][9][10][11][12][13][14][15][16][17][18] GHz in a relative large temperature range, is critical but not particularly designed and investigated by now.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

Zhou

Yin

et al. 2018

J Am Ceram Soc

View full text Add to dashboard Cite

With the aim to design a particular material for low and high frequency cooperative electromagnetic absorption at high temperature, a multiscale design is proposed by combining the microstructure and meta‐structure in one material. The SiCf/Si3N4 composite is prepared via the chemical vapor infiltration technique with SiCf as the EM wave absorbing phase and Si3N4 as the wave‐transparent ceramic matrix. The crossing grooved meta‐structure is designed and fabricated to further improve its absorbing properties and to guarantee its absorbing capacity stability at high temperature. A minimum reflection loss of −15.3 dB and −14.8 dB can be reached at 8 and 18 GHz with a total thickness of 5 mm. The temperature‐dependent reflection loss of the designed meta‐structure keeps relative reliable high temperature absorbing performances from room temperature to 500°C. This effective enhanced EM wave absorbing property is believed to be a consequence of multiscale effect induced by combining the traditional EM absorbing materials with metamaterial structure.

show abstract

Section: Temperature-dependent Em Wave Absorbing Propertiesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

Zhou

Yin

et al. 2018

J Am Ceram Soc

View full text Add to dashboard Cite

show abstract

“…In recent years, numerous materials have been used in the design, preparation and research of RACs, including metal oxides, ceramics, and carbon-based materials, such as Si3N4, SiCf/SiC, TiC, Ti3SiC2, ZnO, MnO2, carbon fibers, CNTs and graphene [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] .…”

Section: Introductionmentioning

confidence: 99%

High temperature metamaterial enhanced electromagnetic absorbing coating prepared with alumina ceramic

Zhao

Shao

et al. 2021

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

High Temperature Metamaterial Enhanced Electromagnetic Absorbing Coating Prepared With Alumina Ceramic 

Zhao

Shao

et al. 2021

Preprint

View full text Add to dashboard Cite

At present, a series of challenges are impeding the large-scale application of the high temperature radar absorbing coatings (RACs), such as the complex preparation of raw material and the complicated technology of processing. In this paper, a new, thin and high-temperature metamaterial RAC (MRAC) with strong absorption was designed and experimentally demonstrated, composing of a radar absorbing coating and a layer of metamaterial. To avoid the need for the complex preparation of raw materials, pure alumina was selected as the radar absorbing coating. Meanwhile, plasma spraying and screen printing were employed to simplify the manufacture technology to produce the absorbing coating and the metamaterial layer, ensuring its feasibility and practicality. The metamaterial layer was prepared with a high temperature conductive paste and it improved the impedance matching of the coating and regulated the electromagnetic (EM) resonance. With the ability to consume more incident EM waves, excellent absorption performance at high temperature was achieved with relatively small thickness. In the 8 ~ 18 GHz band, the MRAC bandwidth for reflection loss (RL) below -5dB almost covered the frequency of 10 ~18 GHz with a thickness of only 1.5 mm at 800 ℃. This new metamaterial has broad application prospects by the virtue of its simplicity and ease of production.

show abstract

Temperature dependence of dielectric properties of SiCf/PyC/SiC composites

Cited by 25 publications

References 35 publications

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

High temperature metamaterial enhanced electromagnetic absorbing coating prepared with alumina ceramic

High Temperature Metamaterial Enhanced Electromagnetic Absorbing Coating Prepared With Alumina Ceramic

Contact Info

Product

Resources

About

Temperature dependence of dielectric properties of SiCf/PyC/SiC composites

Cited by 25 publications

References 35 publications

Multiscale designed SiCf/Si3N4 composite for low and high frequency cooperative electromagnetic absorption

Multiscale designed SiCf/Si3N4 composite for low and high frequency cooperative electromagnetic absorption

High temperature metamaterial enhanced electromagnetic absorbing coating prepared with alumina ceramic

High Temperature Metamaterial Enhanced Electromagnetic Absorbing Coating Prepared With Alumina Ceramic&nbsp;

Contact Info

Product

Resources

About

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

Multiscale designed SiC_f/Si₃N₄ composite for low and high frequency cooperative electromagnetic absorption

High Temperature Metamaterial Enhanced Electromagnetic Absorbing Coating Prepared With Alumina Ceramic