COMPOSITES PART B-ENGINEERING
·
2023
·
IF 13.1
Yang Lyu,Yuan Cheng,Guangdong Zhao,Mengyu Wang,Guiqing Chen,Xinghong Zhang,Wenbo Han
The SiBCN(Zr) ceramics were synthesized via a polymer-derived ceramics route. Using this precursor, the precursor impregnation pyrolysis process prepared the C f /SiBCNZr composites with low density (1.89 g/cm 3 ). Compared to C f /SiBCN, the C f /SiBCNZr composites exhibit reliable thermal stability and ablation resistance in a wide temperature range. A dense oxide layer dominated by ZrO 2 and SiO 2 formed in situ on the surface of C f/ SiBCNZr, effectively preventing outside oxygen and further ablation. The introduced Zr is evenly distributed in SiBCN ceramics, which enables it to give full play to the ablation resistance of Zr at higher oxygen acetylene torch temperatures. This work enriches the fundamental understanding and offers engineering guidance for lightweight ultra-high temperature ceramic matrix composites .
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·
IF 3.5
Wenhao Dou,Bingzhu Wang,Daxin Li,Haobo Jiang,Xiaoliang Sun,Ling Li,Yingying Wang,Zhihua Yang,Dechang Jia,Yu Zhou
To enhance the ablation resistance of porous C sf /MA–SiBCN composites, the polymer infiltration and pyrolysis (PIP) process is adopted to obtain layered C sf /SiBCN composites containing MA–SiBCN and PDCs–SiBCN. After ablation for 10 s, the ablative layer fails to remain on the C sf /MA–SiBCN surface with mass ablation rate of 0.062 g/s and linear ablation rate of 0.208 mm/s, while the dense C sf /SiBCN surface is covered by a dense and stable ablative layer mainly consisting of amorphous SiO 2 glassy phase due to the synergistic ablation effect of MA–SiBCN and PDCs–SiBCN, which could resist the intense scour by ablation flame and prevent internal corrosion, and thus the ablation resistance improves with a 37% decrease in mass ablation rate (0.039 g/s) and an 18% decrease in linear ablation rate (0.171 mm/s), respectively.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2024
·
IF 4.1
Xingang Luan,Qinghua Zhao,Xuefei Sun,Shaomin Gu,Xichao Dong,Laifei Cheng,Ralf Riedel
Aiming at the lack of stable and reliable electrode materials for high temperature wireless sensors , a solution was proposed to use SiBCN ceramic as thin film electrode. To optimize the conductivity of SiBCN coatings, different conductive fillers were incorporated into the precursor solution to prepare conductive SiBCN coatings and the relationship between the coating process parameters, surface morphology and conductivity was established. The results show that the microstructure of the composite can be adjusted in terms of the HfB 2 /CNT ratio to optimize the electrical conductivity . HfB 2 and CNTs are evenly distributed in the coating by adding dispersants and ground SiBCN self-fillers. The electrical conductivity of SiBCN coatings can be greatly enhanced by adding HfB 2 and CNTs fillers. Integrating conductive fillers such as HfB 2 and CNTs can form a diafiltration path and the resistivity of the prepared coating has been determined to be as low as 0.13 ± 0.01 Ω m. The conductivity did not necessarily increase with an increasing amount of fillers. Adding a balanced amount of filler particles to the ceramic matrix is the requirement for optimizing the electrical conductivity of the coating.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
KEY ENGINEERING MATERIALS
·
2012
·
IF 0
Si Hui Wang,He Yun Wang,Fan Xing Meng,Ya Li Li
Abstract: The introduction of metal atoms into SiBCN network allows the development of novel high temperature ceramics and functional ceramics. In this work, cerium (Ce) containing polyborosilazane (PBSZ) is synthesized through substitution and polymerization reactions. Ce atoms are incorporated into PBSZ through the lithium replacement of H in PBSZ followed by Ce replacement of lithium. The chemical structure of the PBSZ and as-synthesized Li containing PBSZ are analyzed by Fourier transform infrared (FTIR) shows that the bands at 598 and 1183 cm-1 which can be assigned to Li-N and Si-N-Li stretching. It is suggested that lithium is incorporated into PBSZ. PBSZCe is transformed into SiBCNCe ceramic by pyrolysed in argon. Scanning electron microscope shows that the SiBCNCe ceramics are porous on the surface and corallike in the section. The chemical bondings of SiBCNCe ceramics are BN, the BN, SiC and Si3N4 characterized by X-ray photoelectron spectroscopy.
研究领域:
材料科学
·
无机化学
✓ 已验证
DOI
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2020
·Vol. 104
·期 4
·1772-1784
·
IF 3.502
Jinxue Ding,Fengbo Chen,Jianxin Chen,Jin Liang,Jie Kong
Demand for high-performance electromagnetic (EM) wave absorbing materials with high-temperature resistance is always urgent for application in a harsh environment. In this contribution, two-dimensional material, Ti 3 C 2 T x MXene, was introduced into a hyperbranched polyborosilazane. After pyrolyzation, the as-prepared TiC/SiBCN ceramics present excellent EM wave absorption in X-band. The TiC nanograins appearing after annealing provide multilevel reflection and interface polarization. Dipole polarization formed at interface defects, in company with interfacial polarization, also makes a great contribution to enhanced EM wave absorption. The TiC/SiBCN nanocomplex prepared with 5 wt% Ti 3 C 2 T x MXene possesses a minimum reflection coefficient of −45.44 dB at 10.93 GHz and abroad bandwidth 8.4 and 12.4 GHz, almost covering the entire X-band. Tuning the thickness in the range of 2.35-2.54 mm, the effective absorption band can achieve the entire X-band. And the EM wave absorbing performance has been maintained to a large extent at 600°C with the minimum reflection coefficient of −26.12 dB at 12.13 GHz and the effective absorption bandwidth of 2 GHz. Last but not the least, TiC/SiBCN ceramics offer a good thermal stability in argon as well as in air atmosphere, making it possible to serve in high-temperature detrimental environments. This study is expected to provide a new perspective for the design of high-performance absorbing materials that are able to be used in harsh environments, especially in high temperatures.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Bijie Wang,Yujie Song,Xiao Zhang,Ke Chen,Ming Liu,Xiao Hu,Liu He,Qing Huang
SiBCN ceramics have excellent high-temperature stability and anti-oxidation properties, and they are candidates for materials used at extreme conditions. In this paper, amorphous SiBCN(O) ceramics were obtained through pyrolysis of cross-linked polyborosilazanes. The element content could be readily tuned through adjusting the structures of polymer precursors. The cerminization process and microstructure evolution process were systematically investigated. The SiBCN(O) ceramics remain amorphous below 1400 °C. The carbothermal reduction was suppressed because of the presence of boron. The SiBCN(O) ceramics showed 95.7% and 99.2% carbon residual in argon and air at 1600 °C, indicating high-temperature stability and good anti-oxidation properties. These SiBCN(O) precursors/ceramics could be potentially used in composites or protective coatings for harsh environments.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Chunmiao Liu,Yanchun Tong,Chang Liu,Jie Liu,Haibin Sun,Qiangqiang Hu,Shigang Wu,Yujun Zhao,Jiao Li,Xue Guo,Yurun Feng
In this work, novel and efficient SiBCN(Fe) nanofibers were successfully prepared by electrostatic spinning and polymer-derived ceramic (PDCs) methods, and their electromagnetic wave (EMW) absorption properties were investigated after pyrolysis at 1100–1500 °C. Notably, SiBCN(Fe) nanofibers exhibit the best EMW absorption performance after pyrolysis at 1400 °C, with a minimum reflection loss (RL min ) of −72.87 dB at 3.6 GHz and an effective absorption bandwidth (EAB, RL≤ −10 dB) of 4.34 GHz at 1.44 mm. Its excellent EMW absorption performance is attributed to its fiber structure, which facilitates the multi-level reflection and scattering of EMW. Meanwhile, the doping of Fe facilitates the in-situ generation of substances such as Fe 3 Si, which can impart SiBCN(Fe) nanofibers with magnetic loss and perfect impedance matching performance. The simulated radar cross-section (RCS) results show that the optimized SiBCN(Fe) nanofibers can effectively achieve the attenuation of EMW in a practical environment. Compared with many previously reported magnetic hybrid composites, SiBCN(Fe) nanofibers exhibit excellent electromagnetic absorption properties with a simpler preparation process, which have the potential to be used as lightweight, ultra-strong radar-absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xishi Wu,Tongzhou Chen,Bijie Wang,Yujie Song,Qing Huang,Zhengren Huang
In this study, novel polyborosilazane-derived SiBCN(O) ceramic was used as self-healing component in self-healing C f /SiBCN(O) composite, which was prepared by polymer infiltration and pyrolysis (PIP) process. Molecular-level structure design of boron-containing ceramic precursors was utilized to achieve uniform dispersion of boron-containing self-healing components in prepared composites. No elemental diffusion was observed at the interface of ceramic matrix and carbon fibers, which resulted in stable SiBCN(O) structure. In addition, boron was uniformly distributed in C f /SiBCN(O) composite ceramic matrix , which was beneficial for self-healing of cracks. Cracks and indentations were able to heal at high temperatures in air. The best crack-healing behavior occurred in air atmosphere at 1000 °C, with nearly complete crack healing. This excellent self-healing behavior was achieved because silicon and boron atoms in SiBCN(O) ceramic reacted with available oxygen at high temperatures to form SiO 2 (l), B 2 O 3 (l), and B 2 O 3 ·xSiO 2 liquid phases, which effectively filled cracks. In general, as-prepared C f /SiBCN(O) composite exhibited excellent self-healing properties and shows great application potential in high-temperature environment applications such as aviation, aerospace, and nuclear power.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Wenhao Dou,Daxin Li,Bingzhu Wang,Zhihua Yang,Dechang Jia,Ralf Riedel,Yu Zhou
The microstructural evolution of C sf /SiBCN composites and formation mechanism of the oxide layer after oxidation for 1–10 h at 1500 ℃ were studied. As the oxidation time increases to 10 h, the macrostructure of the porous C sf /MA-SiBCN composite collapses obviously, while the C sf /SiBCN composite densified via the polymer infiltration and pyrolysis (PIP) process maintains structural integrity due to the formation of the oxide layer with a tri-layer structure: the outermost loose layer mainly containing cristobalite, the dense interlayer of amorphous glass and the innermost layer of some unoxidized BN(C) and SiC grains embedded into the amorphous glass, which hinders the diffusion of oxygen.
研究领域:
材料科学
·
复合材料
·
氧化行为
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Guoxuan Xu,Ketao Hu,Rui Zhou,Ruizhe Xing,Jie Kong
This work introduces a novel digital light processing (DLP) printable SiBCN(O) ceramic precursor (UV-hPBSZ), derived through a straightforward aminolysis approach. The unique hyperbranched molecular structure of UV-hPBSZ leads to remarkable UV curing efficiency, excellent printability, satisfied ceramic yield, and consistent shrinkage ratio. UV-hPBSZ also exhibits superior resistance against cracking and collapse during the polymer-to-ceramic process, thus enabling the fabrication of intricate SiBCN(O) ceramic structures. Upon pyrolysis at 1200 °C, the resulting SiBCN(O) ceramic demonstrates outstanding electromagnetic wave (EMW) absorption performance, achieving full coverage in the X band ( R L min = -36.68 dB). To showcase the design flexibility, a distinctive metastructure is proposed and successfully fabricated using DLP printing technique. This SiBCN(O) metastructure absorber enables impressive EMW absorption in the Ku band (94.6 % coverage), attributed to surface resonance effects and multiple internal reflections. Moreover, SiBCN(O) ceramics exhibit excellent high-temperature stability, with less than a 1.63 % total mass change from room temperature to 1400 °C. UV-hPBSZ offers a simple but versatile way to control dielectric properties, which opens up new possibilities for multifunctional integrated EMW absorbers suitable for both ambient and high-temperature conditions.
研究领域:
材料科学
·
陶瓷工程
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Chunmiao Liu,Yanchun Tong,Chang Liu,Haibin Sun,Qiangqiang Hu,Shigang Wu,Yujun Zhao,Jiao Li,Xue Guo,Yurun Feng
SiBCN ceramic materials are widely studied in electromagnetic wave (EMW) absorption. However, their practical application is limited due to the problem of poor impedance matching. In this study, SiBCN (Ni) fibers were successfully prepared by doping magnetic metal Ni, and the absorption properties of the samples were systematically investigated at different high-temperature treatments (1200 °C–1500 °C). The results showed that the doping of Ni contributed to the formation of carbon nanotubes (CNTs), which could enhance the improvement of conductive loss performance. Additionally, the catalytic effect of Ni promoted the formation of various crystals, including Ni 2 Si, β-SiC, Si 3 N 4 , and Si 2 N 2 O, resulting in the presence of multiple heterogeneous interfaces and excellent polarization loss capability. The Ni 2 Si particles acted as magnetic loss units, thereby enhancing the impedance matching of the fibers. Consequently, the SiBCN (Ni) sample prepared at 1300 °C exhibited a minimum reflection loss (RL min ) of −21.38 dB and an effective absorption band (EAB) of 3.68 GHz. In addition, SiBCN (Ni) fibers coating proved effective in reducing Radar Cross Section (RCS) signals. Therefore, these findings suggest that SiBCN (Ni) fibers have the potential to serve as EMW absorbers in military radar and satellite communication.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qi Ding,Zikang Zhan,Zongbo Zhang,Ziheng Wei,Zhi Cheng,Jie Gao,Yudong Xue,Lianjun Wang,Yuchi Fan,Wan Jiang
In this work, SiBCN fibers with excellent electromagnetic wave (EMW) absorption performance were fabricated using electrospinning technology, followed by curing, pyrolysis, and heat treatment. Microstructure evolution and EMW absorption performance of SiBCN fibers after heat treatment at 1200–1600 °C were investigated. After heat treatment at 1200 °C, the conductive turbostratic C was precipitated from amorphous SiBCN fibers, resulting in minimum reflection loss (RL min ) reaching −63 dB and efficient absorption bandwidth (EAB) reaching 5.2 GHz. While turbostratic C and nano-SiC grains were simultaneously precipitated from SiBCN fibers heat treated at 1400 °C, and the RL min reached −67 dB. The excellent EMW absorption performance of SiBCN fibers was mainly attributed to the synergistic effect of conductive loss, dipole polarization, and interfacial polarization. This work can guide the fabrication of high-performance EMW-absorbing ceramic fibers.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）