CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yabin Zhang,Wenguang Zhang,Houxiang Yin,Yanlin Wang,Bingbing Wang,Lishuai Zong,Jinyan Wang,Xigao Jian
The robust human–machine interaction systems of the aerospace industry necessitate the development of thermal resistant wave-transparent composites, with a pivotal focus on organic resin matrix. However, enhancing the heat resistance of such materials while preserving other critical attributes has been a formidable challenge. In this study, a novel designed strategy of a dual-curing functional phosphorus-based phthalonitrile monomer (P-ALK-PN) has been proposed. The optimized curing temperatures for intra- or intermolecular Diels-Alder reactions of alkynyl groups and polyaddition reaction of cyano groups resulted in a homogeneous and highly crosslinked N-enriched phthalonitrile system. After curing at 450 °C, the resin, namely P-ALK-PN-450 °C, demonstrated exceptional thermal stability ( T 5% = 644 °C), thermo-oxidative stability ( T 5% = 554 °C), and char yield at 800 °C (90.7 % in N 2 and 67.5 % in air). Their quartz fiber reinforced composites (P-ALK-PN/QFs) were subsequently fabricated by the hot-pressing process. Upon post-curing at 420 °C, P-ALK-PN-420 °C/QF displayed elevated glass transition temperature (550 °C), flexural strength (319 MPa), and relatively low dielectric properties with a dielectric constant (D k ) of approximately 4.2 and a dissipation factor (D f ) less than 0.02 across a wide temperature ranging from 25 °C to 600 °C. Especially, it exhibited excellent flame retardancy (only a 6.7 % weight loss at ambient temperatures exceeding 1300 °C for 200 s) as well, stemming from release of eco-friendly inert gases (NH 3 ) and formation of a graphitized protective layer during pyrolysis. These promising results highlight the potential applications of P-ALK-PN resins in aerospace and high-performance engineering fields.
研究领域:
材料科学
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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
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2021
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IF 5.302
Rufei Chen,Wenyan Duan,Gong Wang,Bingshan Liu,Yantong Zhao,Shan Li
Wave-transmitting materials are a kind of multi-functional materials that protect the normal operation of communication and guidance systems of spacecraft in harsh environments. In this paper, we fabricate a broadband microwave transparent Si 3 N 4 -SiO 2 composite ceramic with excellent performance through digital light processing (DLP) 3D printing technology. The influences of sintering temperature on the weight increase rate, density, dimensional shrinkage, phase composition, microstructure, bending strength and dielectric properties of Si 3 N 4 -SiO 2 ceramic were all systematically studied. The strength of Si 3 N 4 -SiO 2 ceramic sintered at 1350 ℃ was 77 ± 5 MPa. The relative permittivity of the ceramic is within the range of less than 4, and the loss tangent can be below 0.003. The 3D printed Si 3 N 4 -SiO 2 ceramic material exhibited excellent wave-transparent performance.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
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2023
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IF 9.9
Tong Zongwei,Yan Xiangjie,Wang Yuexiang,Li Kexun,Ma Weihai
Increasing porosity is one of the most direct ways to improve the thermal insulation and dielectric properties of materials. Until now, many wet methods for preparing Si 3 N 4 ceramic foams usually face the problems of complex rheology, long period, and expensive cost, and the reported pore sizes of Si 3 N 4 ceramic foams are typically micron-grade, resulting in a lack of competitiveness in thermal insulation and wave-transparent applications. In this paper, the Si 3 N 4 @SiO 2 ceramic foams were prepared using an efficient dry-method, which combined three processes of low temperature chemical vapor deposition (LTCVD), template, and isostatic pressing. The method has the advantages of simple operation and short preparation period, and can realize near-net size molding and mass production. In addition, the evolution mechanisms of honeycomb microstructure and composition of Si 3 N 4 @SiO 2 ceramic foam during sintering were studied by chemical reaction thermodynamics. The as-prepared Si 3 N 4 @SiO 2 ceramic foam possesses low density (0.377 g·cm −3 ), high compressive strength (7.5 MPa), low thermal conductivity (0.0808 W·m −1 ·K −1 ), and excellent dielectric properties ( ε < 1.32, tan δ < 0.009) in the frequency range of 8–18 GHz, and its maximum working temperature in air can reach up to 1100 °C. It will be recommended to be applied in the interlayer of Si 3 N 4 ceramic radome to improve its thermal insulation and electromagnetic wave transparency performances.
研究领域:
材料科学
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陶瓷工程
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热能工程
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Xiaoqing Wang,Ze Zhu,Zhenfeng Guo,Chenyu Mi,Ziting Huang,Yunguang Yin,Luyi Zhu,Guanghui Zhang,Benxue Liu,Yongshuai Xie,Xinqiang Wang
The rapid development of aerospace requires radomes to achieve the effect of thermal insulation and electromagnetic wave transmission. However, traditional interlayer materials in radomes for thermal insulation are eligible to structural collapse and brittle fracture at high temperatures. Here, MgAl 2 O 4 nanofibers (MANFs) are successfully fabricated from a quasi inorganic/block-copolymer chain segment via molecular design. The MANFs have a laminated geometrical form with tiny pore size, high porosity, and frameworks connected by nanoparticles, resulting in both ultralow density and thermal conductivity that endow them with excellent thermal insulation properties. The MANFs possess unprecedented elasticity from –196 to 1600 °C with a recoverable compression strain of up to 80 % and excellent fatigue resistance for long-term use, which exceeds the reported results of existing fibers. Excitingly, the low dielectric constant enhances the electromagnetic wave transparency of MANFs, making them suitable as a signal transmission material in radomes. The tremendous potential of MANFs promotes the development of thermal insulators with wave-transparent properties used in extreme environments.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHARACTERIZATION
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2024
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IF 4.8
Guandong Liang,Jilie Yuan,Yueguang Chen,Jianqiang Bi,Zhuangzhuang Yin,Shaoyin Wang,Xicheng Gao,Yao Yang,Jinwang Shi,Weiqiang Li
In this study, Zn 8 B 3 H 3 O 14 nanosheets were synthesized through a one-step coprecipitation process and employed as both a boron source and substrate templates for the fabrication of boron nitride nanosheets (BNNSs), which were synthesized efficiently at low temperatures by the borate nitration method using ammonia as the nitrogen source. The thickness of the synthesized BNNSs ranged from 3 to 10 nm with a flake dimension of about 2.56 μm. The prepared BNNSs using this method realized 98.8% boron source utilization and single batch yields up to gram level. In addition, BNNSs/SiO 2 microwave-transparent composites were prepared to investigate the potential for large-scale applications of the BNNSs produced by using this method. The composites demonstrated a remarkable increase in bending strength and fracture toughness, reaching 122.02 MPa and 2.31 MPa·m 1/2 , respectively, with the addition of only 0.5 wt% BNNSs. Compared with SiO 2 without BNNSs, the fracture toughness of the composites is increased by 106%. A novel crack plugging strong toughening mechanism of BNNSs is proposed. Simultaneously, the composites exhibit exceptional microwave-transparent properties, with dielectric constants below 4 in the real part and below 0.03 in the imaginary part. Therefore, this study has successfully achieved the low-temperature and efficient synthesis of micron-scale BNNSs, laying the groundwork for their large-scale application.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2025
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IF 14.1
Xu Fu,Yizhou Shen,Lingfeng Zhao,Weixin Zhu,Weilan Liu,Chenliang Li,Yuebin Lin,Zongsheng Ye,Chengfeng Shen
Aircraft confronting harsh meteorological conditions and radar detection environments during high-altitude flights face significant risks, which can threaten flight safety. This study designs and fabricates a novel Jerusalem cross-inspired Frequency Selective Surface (FSS). Initially, rGO powder with an optimized reduction degree is synthesized as the conductive filler. Based on this, the rGO/WPU electrothermal coating is prepared using the spraying method, demonstrating excellent electrical conductivity and electrothermal performance. Subsequently, a New Jerusalem Pattern Structure (NJPS) is engineered on the coating surface. This patterned design notably improved microwave transmittance. Parameter optimization ensured superior wave transmission performance, with the underlying mechanism explained through antisymmetric surface current analysis. Laser-engraved NJPS samples are tested under both room-temperature and low-temperature conditions, confirming dual functionality: effective Joule heating and stable broadband transmission. Importantly, icing wind tunnel tests under simulated flight conditions verified the de-icing capability within 216s via interfacial water-film lubrication. This patterning strategy establishes a viable methodology for reconciling electrothermal de-icing and electromagnetic transparency on aircraft surfaces.
研究领域:
材料科学
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航空航天工程
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功能高分子材料
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电磁学
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热力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
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2021
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IF 9.078
Wenxing Jiang,Xianhong Zhang,Dong Chen,Yuhong Ma,Wantai Yang
High-performance cyanate ester (CE) resins with excellent dielectric properties are highly desired in the fields of information and communication technology . Herein, we present an efficient strategy for the preparation of low- k and wave-transparent CE resins modified with a novel kind of bismaleimide (BMI) hollow polymer microspheres (BMI-HPPs). Benefiting from both the superior properties of BMI and the unique hollow structure, BMI-HPPs can serve as an effective modifier to reduce dielectric constant (ε) of the CE resins and simultaneously improve their toughness. There are plenty of pendant vinyl groups and unreacted maleimide groups on the surface of BMI-HPPs, which could effectively copolymerize with CE monomer , leading to a lower curing temperature and better interfacial compatibility. The BMI-HPPs/CE resin with 7.5 wt% BMI-HPPs exhibited minimum values of ε and dielectric loss (tanδ) (2.46, 0.006) at 16 GHz, much lower than those of the pristine CE resin (2.92, 0.018), and the corresponding wave transmission was 93.8%–97.1% in the frequency range of 15–18 GHz. Moreover, the modified CE resin showed a maximum impact strength of 18.8 kJ/m 2 at 5 wt% loading of BMI-HPPs, which is 64% higher than that of the pristine CE resin. Because of low- k dielectric properties, superior wave-transparent performance and highly enhanced toughness , the BMI-HPPs/CE resins have great potential in the fields of microelectronics and aerospace.
研究领域:
材料科学
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高分子化学
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电气工程
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微电子
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）