COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2024
·
IF 8.1
Pan He,Yuelei Pan,Mingyuan Yan,Lunlun Gong,Long Shi,Xudong Cheng,Heping Zhang,Junchao Zhao
Silicon Carbide (SiC) aerogel is a material with 3D network structure, low density, and high-temperature resistance, showing a broad application potential in various areas. It is currently challenging for SiC aerogels to balance the mechanical and high-temperature insulation properties. Here, a novel strategy was implemented for the first time, by constructing coaxial precursors. This structure can achieve in-situ Si-C binding and maximization the reaction sites to achieve fibers growth uniformly. The sintering time is reduced by over 90%. The fatigue resistance and elastic properties of the SiC aerogel were significantly improved. In addition, the uniform nanowire fiber and pore structure enable an ultra-low thermal conductivity of 0.018 W/(m K) at room temperature, 0.082 W/(m K) even at 900 °C, and superior structural stability at 1400 °C. Our strategy provides a feasible approach for the structural design of thermally insulated SiC aerogels with high elastic resilience and good adsorbability.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Fuhao Xu,Yixian Wang,Fangchen Tang,Xiaolei Dai,Zhiyang Zhao,Yong Kong,Xiaodong Shen,Gaofeng Shao
As space science and technology rapidly advance, spacecraft are increasingly subjected to severe thermal and electromagnetic environments. This has created an urgent demand for materials that offer both microwave absorption and thermal insulation. Herein, we present one-dimensional (1D) carbon nanotube (CNT)/SiC nanostructure-reinforced SiC-based aerogels via carbothermal reduction of resorcinol-formaldehyde/silica composite aerogels containing CNTs. These composite aerogels were presynthesized using a straightforward one-pot sol-gel method, subsequently undergoing supercritical CO 2 drying. Conduction loss and mechanical strength are both simultaneously improved by the in-situ formation of 1D CNT@SiC core-shell nanostructures within granular SiC aerogels. The optimized SiC-based aerogel demonstrates exceptional performance, achieving a minimum reflection loss of −66.01 dB and the effective absorption bandwidth reaching 6.76 GHz. Additionally, it maintains a thermal conductivity of 0.0582 W/(m·K) at 25 °C, alongside a Young's modulus of 45.2 MPa at a density of 0.242 g/cm 3 . This design seamlessly combines various functionalities within the SiC-based aerogel system, offering significant guidance towards the development of cutting-edge functional aerogels designed to withstand extreme environmental challenges.
研究领域:
材料科学
·
航天工程
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Jingxiang Liu,Zhen Wang,Haoquan Hao,Qinghe Jing,Shouqing Yan,Jie Guo,Wentao Liu,Zhijiang Wang
SiC aerogels have been extensively studied for electromagnetic wave (EMW) absorption because of their tunable dielectric properties. Continuous dual-peak EMW absorption can broaden the effective absorption bandwidth (EAB); however, few SiC aerogels have been reported to exhibit this phenomenon and the mechanisms to achieve this through microstructure design remain unclear. In this study, size-tunable nanopores were constructed in SiC aerogel by a simple carbothermal reduction method, which gradually increase with increasing reaction temperature. The mechanism of the nanopore formation in SiC aerogels is also discussed in detail. The optimized SiC aerogel prepared at a reaction temperature of 1550 °C exhibited continuous dual-peak EMW absorption with a maximum EAB of 6.24 GHz (11.76–18 GHz), full Ku-band coverage, and minimum reflection loss of −32.59 dB. This continuous dual-peak EMW absorption was ascribed to the overlap of the secondary peak caused by the nanopore-induced strong dielectric resonance and the main peak caused by SiC. The results of this study will provide inspiration for the design of microstructures for continuous dual-peak absorption in EMW absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xinli Ye,Haiyang Zhang,Hao Yu,Jianqing Xu,Shan Li,Xiaomin Ma,Wei Xu,Junxiong Zhang
High-performance SiC aerogels are sought after for their superior thermal insulation and absorption properties, especially in applications such as electromagnetic stealth for aero engines and high-temperature radar stealth. However, achieving SiC aerogel with both temperature resistance and strong wave absorption while controlling their properties remains a significant challenge. This study investigates the influence of reactant concentrations on the structure, thermal insulation, and absorption performance of SiC aerogels synthesized via the sol-gel method. The aerogel synthesized with a n(C):n(Si) ratio of 1:2 showed superior thermal insulation. Additionally, it showed excellent electromagnetic wave absorption, with a minimum reflection loss of −53.80 dB at 6.16 GHz and a maximum effective absorption bandwidth of 3.10 GHz at a thickness of 2.40 mm. Furthermore, the maximum compressive strength of C/SiC@SiC reached 0.98 MPa, a notable improvement of 81.48 % compared to the pristine C/SiC matrix. The maximum effective absorption bandwidth of C/SiC@SiC was increased to 6.06 GHz at 2.35 mm, and the surface center temperature decreased from 183.1 °C for C/SiC to 130.1 °C for C/SiC@SiC. Overall, this study offers valuable insights into the development of advanced absorption and thermal insulation materials, providing a foundation for further research and innovation in this field.
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
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zhen Wang,Hairui Zhao,Ding Dai,Haoquan Hao,Zhijiang Wang
SiC aerogel is a novel candidate for electromagnetic absorption (EMA) materials in extreme environments because of its ceramic nature and aerogel morphology. In this study, graphene oxide (GO), which having has been generally serving served as a “brick” in the material community, was used as a building block to prepare SiC aerogel precursors and further develop a novel and designable route for preparing SiC aerogel for EMA. The experimental results suggested that the GO aerogel was well converted into a SiC aerogel with ultra-low density (<4 mg cm −3 ). The synthesized SiC aerogel inherited the precursor well in structure while having a wide absorption band (approximately 5.5GHz) and a high absorption frequency-to-thickness correlation different from traditional SiC aerogels. The above idea for designing and assembling SiC aerogels will significantly broaden the practical applications of GO and SiC in EMA, supercapacitors and sensors.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Mingyuan Yan,Xudong Cheng,Long Shi,Yuelei Pan,Pan He,Zhongxin Zhang,Zhiyi Lun,Yangyang Fu,Heping Zhang
Silicon carbide (SiC) aerogels with high porosity and excellent thermal stability are a promising thermal insulation and adsorption material. However, the poor mechanical properties of SiC aerogels greatly limit its practical application. Herein, inspired by flexible palm bark, for the first time, we report a novel method called “bioinspired link assembly” (BLA) to fabricate bioinspired SiC aerogels (BSA) with significant layered structure. The layered structure and elastic links are in situ constructed in bioinspired link assembly process. The BLA method optimizes structure of the BSA by regulate monolayer dimensions. Owing to the elastic links between the layered structures, the BSA can be bent 180°. Moreover, the BSA shows super-elasticity (elastic deformation up to 70 %) and fatigue resistance (100000 compressions). Benefiting from layered structure, the BSA exhibits an ultralow thermal conductivity (0.027 W m −1 K −1 ). In addition, BSA shows excellent absorption capacities (weight gain about 44 ∼ 72 times) for organic solvents. Therefore, the excellent comprehensive properties make BSA have broad application prospects in the fields of high temperature thermal insulation and oil pollution treatment.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2019
·Vol. 89
·期 3
·623-633
·
IF 1.986
An Zhimin,Ye Changshou,Zhang Rubing,Qu Qiang
Abstract A C/SiO 2 /SiC ternary aerogel was prepared from a formaldehyde–catechol/silicon source via the sol−gel method, supercritical drying, and high-temperature carbothermal reduction. The effects of different carbon/silicon molar ratios on the microstructure, chemical composition, and mechanical and shielding properties of the C/SiO 2 /SiC aerogels were investigated. The fabricated aerogels exhibited low density of 0.118–0.271 g/cm 3 , low thermal conductivity of 0.044 to 0.089 W/(m∙K) and a high specific surface area of 774 m 2 /g. The aerogel exhibited electromagnetic interference shielding effectiveness (SE) properties; the maximum SE value was 24 dB over 12.4–18.0 GHz with an absorption-dominant shielding characteristic. To improve the mechanical properties of the ternary aerogel, novel SiC w -C/SiO 2 /SiC aerogel composites were prepared by adding different contents of SiC whiskers into precursor solutions. The mechanism affecting thermal and mechanical properties of aerogel composites was investigated. This composite having high strength and low thermal conductivity had potential applications in space shuttles and reusable carrier thermal protection materials.
The fabricated C/SiO 2 /SiC ternary aerogels exhibited low density of 0.118–0.271 g/cm 3 and low thermal conductivity of 0.044−0.089 W/(m∙K). The aerogel exhibited electromagnetic interference shielding effectiveness (SE) properties; the maximum SE value was 24 dB over 12.4–18.0 GHz with an absorption-dominant shielding characteristic.
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 Materials Research and Technology-JMR&T
·
2025
·
IF 6.6
Chunxue Zheng,Jie Yu,Xinyang Li,Jingbo Duan,Zhulin Huang,Ming Li,Xiaoye Hu,Yue Li
High-temperature thermal-insulation aerogels with high mechanical strength and well oxidation resistance are critical for the thermal protect system (TPS) of aerospace vehicles. However, it is still challenging to achieve large-scale preparation of aerogels that integrate the above functions through a simple method. In this work, carbon fiber (CF) felts are introduced as a reinforcement and template to prepare silicon carbide nanowire (SiC nw ) aerogel composites through a simple in-situ growth strategy. The high-strength CF as the skeleton endows high mechanical strength, and the in-situ grown SiC nw aerogels lead to good thermal insulation of the composites. More importantly, a dense SiC shell was also formed and tightly coated on the surface of CF (CF@SiC) during the in-situ growth process, which effectively protects the CF from oxidation, thus enhancing the high temperature oxidation resistance of the composites. As a result, the optimal CF@SiC/SiC nw aerogel composites possess a low thermal conductivity of only 0.056 W m −1 K −1 at room temperature. The back temperature of the 9 mm thick composites is only 151.9 °C after exposure to a butane flame at 1220 °C for 300 s, and it still maintains considerable thermal insulation and mechanical properties after the ablation. In addition, the machinability of the CF felts makes it easy to prepare the composites in various shapes and larger sizes. This work provides a simple and scalable strategy to synthesize reliable SiC-based aerogel composites for high-temperature thermal insulation applied in extreme environments.
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
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Mingyuan Yan,Xudong Cheng,Lunlun Gong,Zhiyi Lun,Pan He,Long Shi,Chenjie Liu,Yuelei Pan
Owing to excellent high temperature resistance, high porosity and light weight, SiC aerogels possess great application prospects in thermal insulation and adsorption. However, poor mechanical properties of SiC aerogels, such as brittleness and non-bendability, hinder its application; it is still a challenge to improve and regulate the mechanical properties of SiC aerogels. Here, for the first time, we propose a micromechanical design strategy to prepare flexible SiC nanowire/mullite fiber composite aerogels (SMCAs). By optimizing the aspect ratio of the skeleton fibers to regulate the stress state of microstructures, the maximum compressive stress of that SMCAs could bear can be tuned systematically from 1.2 kPa to 1254.8 kPa, spanning 3 orders of magnitude. More importantly, thanks to its micromechanical design, SMCAs can withstand up to 80% compression deformation and up to 90° bending deformation. The present work provides a new idea for the regulation of mechanical properties of ceramic aerogels.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2023
·
IF 17.1
Xuan Zhang,Jianyong Yu,Cunyi Zhao,Yang Si
SiC is an exceptionally competitive material for porous ceramics owing to its excellent high-temperature mechanical stability. However, SiC porous ceramics suffer from serious structural damage and mechanical degradation under thermal shock due to the hard SiC microstructure and weak bonding networks. Here, we report a scalable interface-engineering protocol to reliably assemble flexible amorphous SiC nanofibers into lamellar cellular meta-aerogels by designing a covalent heterointerface. This approach allows the construction of a strong binding architecture within the resilient nanofiber skeleton network, thereby achieving structurally stable, mechanically robust, and durable SiC porous ceramics. The optimized amorphous SiC meta-aerogels (a-SiC MAs) exhibit the integrated properties of ultralight with a density of 4.84 mg cm–3, temperature-invariant superelastic, fatigue-resistant at low 5% permanent deformation after 1000 cycles of compression, and ultralow thermal conductivity (19 mW m–1 K–1). These characteristics provide a-SiC MAs potential application value in the thermal protection field.
研究领域:
材料科学
·
机械工程
·
纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）