SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Peng Liu,Xi Tan,Hao Ren,Wei Liu,Linwen Jiang,Xiaofeng Zhang
To improve the long-term oxidation resistance of SiC fibers, a novel yttrium-doped lanthanum monazite (Y-LaPO 4 ) coating was deposited onto the surface of SiC fibers (Y-LaPO 4 /SiC f ) by a simple hydrothermal method . The static oxidation behavior of Y-LaPO 4 /SiC f , SiC fibers coated with lanthanum monazite (LaPO 4 /SiC f ), and SiC fibers without coatings (SiC f ) was studied at 1350 °C for 50 h. The results indicated that yttrium diffused into the oxide scale during oxidation process. The thicknesses of the oxide scales for the oxidized fibers in Y-LaPO 4 /SiC f and LaPO 4 /SiC f were about 4.56 and 11.31 μm. SiC fibers without coatings were completely oxidized to silica . Furthermore, the oxidation kinetic curves of SiC f , LaPO 4 /SiC f , and Y-LaPO 4 /SiC f exhibited a parabolic trend during oxidation for 15, 20, and 50 h. Calculated the oxidation rate constants of SiC f , LaPO 4 /SiC f , and Y-LaPO 4 /SiC f were found to be 1.37, 1.08, and 0.40 μm 2 /h, respectively. The system of Y-LaPO 4 coatings not only retains LaPO 4 as a framework of the interface, but also incorporates yttrium to improve the oxidation resistance of fibers. Therefore, doping yttrium in lanthanum monazite can enhance the adherence between coatings and oxide scales and improve the oxidation resistance of SiC fibers.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2024
·
IF 12.7
Yu Zhang,Xu Shen,Qin Ma,Shuang Mu,Shaoming Dong,Jinshan Yang
In this work, the mechanical behavior of NITE-SiC f /SiC composites, accompanied by the damage mechanisms of SiC fibers and BN interphase during NITE process, are investigated. The results show that the fracture characteristic of NITE-SiC f /SiC composite is transformed from quasi-ductile mode to brittle mode with the elevating temperature, as well as severe damage of SiC fiber and BN interphase. The damage of SiC fibers is originated from high temperature, sintering aids corrosion and matrix compression. High temperature and sintering aids diffusion lead to the grain growth and strength degradation of SiC fibers. The damage of BN interphase is caused by the sintering aids corrosion, mainly the reaction of Al 2 O 3 , and matrix compression. The stress distribution is simulated via finite element analysis proving that up to 17.5 GPa and 17.0 GPa stress originated from matrix shrinkage during sintering process is applied to the fiber and interphase respectively, making the fiber deformation and interphase fragmentation. The degraded fiber strength and destroyed interphase structure weaken the load-bearing capacity and crack deflection ability, causing degradation of mechanical properties and reliability of composites. This work helps to comprehensively understand and optimize the properties of SiC f /SiC composites prepared by NITE process.
研究领域:
材料科学
·
工程学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2022
·
IF 6.364
Yang Li,Maolin Chen,Qinzhao Zhang,Yanzi Gou,Peng Xiao,Pengju Chen,Wei Zhou,Xiaobing Zhou
Y 3 Si 2 C 2 ternary ceramics were in-situ grown on the third-generation Chinese commercial SiC fiber (KD-SA SiC fiber) surface via molten salt method. Microstructures and oxidation/corrosion behavior of in-situ grown Y 3 Si 2 C 2 coated SiC fibers exposed to air and wet-oxygen at 1400 ℃ were investigated. Results indicated that the layered Y 3 Si 2 C 2 slices with thickness of approximately 15 nm can be successfully in-situ grown on SiC fibers. The product on the fibers surface after oxidation/corrosion at 1400 ℃ for 1 h in both ambient air and wet-oxygen are Y 2 Si 2 O 7 and SiO 2 . Moreover, microstructural characterization indicates that the immigration and expansion of gaseous bubbles induced by oxidation product, mainly CO, result in microstructural differences of SiC fiber specimens, and finally oxidation mechanism based on the microstructural difference were proposed.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Jian Qiao,Kehui Lin,Renqiang Shi
To improve the properties of SiC fiber-reinforced ceramic-matrix composites for potential use as radar-absorbing materials, La 2 Ti 2 O 7 interphase was dip-coated on the surface of the SiC fibers, and the SiC f /NBAS composites were then prepared. The pristine SiC fibers with relatively high electrical resistivity were mainly composed of amorphous Si x C y O and a small amount of β -SiC and free carbon. A weak La 2 Ti 2 O 7 interphase improved the flexural strength and toughness of the composites due to the fiber pull-out and crack deflection. The measured room-temperature complex permittivity of the composites increased, and the dielectric loss was greater than that of the pristine SiC fibers owing to the production of excess free carbon in the degradation of SiC fibers during the preparation of SiC f /NBAS composites. The excess free carbon with higher electrical conductivity was also believed to play a significant part in the increase of dielectric permittivity of the composites with the increasing heat-treatment temperatures even below 1000 °C. A dual-layer structure was designed to expand the bandwidth for microwave absorption.
研究领域:
材料科学
·
复合材料
·
电磁学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yi Hou,Baijun Chen,Hui Zhang,Pengyu Wang,Zixin Wang,Zhiqiang Liu,Tiansheng Wang,Lixi Wang
High-temperature resistant performance for thermal end components has always been a key development direction in advanced microwave absorption materials. SiC fibrous materials could be served as the ideal candidate to meet the challenge of both lightweight and high temperature resistance. However, the relatively weak microwave attenuation capacity of pure SiC fibers greatly limit the further application. Herein, highly crystallized SiC nanoparticles (SiC np ) were decorated into the SiC fiber (SiC f ) matrix via co-electrospinning and high temperature pyrolysis. The resultant SiC np @SiC f composite fiber material possesses abundant heterogeneous interfaces to fascinate the dielectric loss, as well as the enhancement of conductivity loss. The optimized SiC np @SiC f sample pyrolyzed at 1300 °C exhibits a minimal reflection loss (RL min ) of −57.04 dB at 6.84 GHz, and the effective absorption bandwidth (EAB) reaches as wide as 7.5 GHz at 2.7 mm. With the filler content of only 10 wt%, the prepared SiC np @SiC f hybrid material could be applied as highly efficient and broadband ceramic microwave absorber.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Binbin Wu,Na Ni,Xiaohui Fan,Xiaofeng Zhao,Ping Xiao,Fangwei Guo
ZrB 2 -SiC coatings with varied porous structures were deposited on SiC fiber tows using the sol-gel method and cured at 1400 ℃ in vacuum. Tensile strength of the coated SiC fibers were much lower than that of the uncoated fibers. The bimodal distribution in the Weibull plot of the coated SiC fibers demonstrated that the fracture of the coated fiber can be attributed to two types of defects: the porous structure of the coating and the fiber defects. Detailed morphology and microstructure characterization of the coating and fiber combined with strength calculation were carried out to investigate the individual contribution of the fiber defects and the porous coating layer respectively. The results revealed that apart from the fiber damage during the coating process the porous structure of the fiber coating has a non-negligible effect on the fiber strength, presumably due to a relatively strong bonding between the fiber and coating.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Chenpei Zhou,Dong Zou,Yutang Kang,Shasha Feng,Zhaoxiang Zhong,Weihong Xing
The high gas permeance of ceramic membranes is the most important indicator of hot-gas filtration. Ceramic membranes made of fibers show significant potential for filtering dust-laden gases owing to their high porosity and high gas permeance. A novel method is proposed for preparing a SiC fiber separation layer on a rigid ceramic support that endows the membrane with a high porosity. However, the interfacial adhesion between the support and separation layers was low as there were insufficient connection points. Therefore, a solvothermal method was proposed for the in-situ vertical growth of TiO 2 nanocords on the surface of a SiC support (SiC–TiO 2 ). Next, a SiC fiber separation layer was deposited on the SiC–TiO 2 support to improve the interfacial adherence. The fabrication parameters of the SiC fiber layer, such as the solid content of the coating slurry and sintering procedure of the separating layer, were investigated in detail. At a SiC fiber content of 6 wt%, spray-coating times of 2, and sintering temperature of 1150 °C, a complete fiber layer was successfully deposited on the rigid ceramic support. The resulting membrane had a thickness of 100 μm, porosity of 91%, average pore diameter of 6.8 μm, and gas permeance of 440 m 3 ·m −2 ·h −1 ·kPa −1 . In the filtration of dust-laden gas containing SiO 2 as simulated dust (average particle size, 0.3 μm), the rejection rate was >99.9%; further, after four cycles of filtration–backwashing, the pressure drop was <0.82 kPa. The outlet dust content was less than 0.1 mg m −3 . Moreover, this membrane exhibited superior filtration ability at 500 °C. The findings of this study can aid the fabrication of ceramic fiber membranes with a high gas permeance and high interfacial adherence for industrial applications.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Chengmou Deng,Huiyong Yang,Juntong Huang,Ruiying Luo,Lianyi Wang,Zhi Chen,Wei Li,Jintao Qiu,Wenpeng Li
SiC fiber bundles with 1–4 HfSiO 4 sub-layers as the interface coating were successfully obtained with detailed optimized preparation parameters via the non-hydrolyzed sol-gel ( NHSG) and dip-coating method. Subsequently, SiC f /SiC minicomposites reinforced with HfSiO 4 -coated fibers were fabricated through a precursor infiltration pyrolysis ( PIP ) process. The tensile behavior and microstructures of the prepared SiC f /SiC minicomposites treated at room temperature, 800 ℃, and 1000 ℃ in an air atmosphere were investigated. The toughening mechanism of the HfSiO 4 interphase in the SiC f /SiC minicomposites and the corresponding anti-oxidant properties were also thoroughly discussed. Results indicate that SiC f /SiC minicomposites with the HfSiO 4 interphase possessed a nearly pseudo-plastic fracture characteristic and significantly enhanced anti-oxidant properties. It is inspired that the properties of the SiC f /SiC minicomposites could be adjusted by controlling the thickness of the HfSiO 4 interphase to acquire desirable properties such as a higher tensile strength or better oxidation resistance.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Lu Zilong,Yue Jianling,Fu Zeyu,Huang Xiaozhong,Yang Haitang
SiC f /BN/SiC mini-composites comprising single tow SiC fibre-reinforced SiC with chemical vapour deposited (CVD) BN interface layers were fabricated. The mechanical performance and binding strength of the composites and the fibre/interface for the oxidized SiC f /BN/SiC mini-composite samples (oxidation at 1000, 1200, 1300, 1400 and 1500 °C in air for two hours) were investigated by tensile tests and fibre push-out tests, respectively. The value of oxidation mass change was also measured. Some unusual phenomena for the SiC f /BN/SiC mini-composites oxidized at 1000 °C were discovered in this work. The tensile strength reached a maximum value, and the mass gain rate showed as a singular negative value, while the shear strength between the fibre and the matrix was moderate. Scanning electron microscopy, energy dispersive spectrometry, infrared spectroscopy and X-ray diffraction characterization methods were used to reveal the microstructural evolution and investigate the unusual phenomenon during oxidation procedures. This work will provide guidance for predicting the service life of SiC f /BN/SiC composite materials and may enable these materials to become a backbone for thermal structure systems in aerospace applications .
研究领域:
材料科学
·
高温复合材料
·
航空航天材料
·
表面工程
·
结构表征
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2020
·
IF 4.495
Dou Chen,Gaoming Mo,Junmin Qian,Liu He,Qing Huang,Zhengren Huang
Polycarbonsilane (PCS) is an important precursor of silicon carbide (SiC) fibers and ceramics. The ceramic yield of PCS is relatively low, about 60 %, which may bring some deficiencies in its applications. In this work, a novel precursor cyano-polycarbosilane (PCSCN) is synthesized by hydrosilylation reaction between PCS and acrylonitrile using a rhodium-containing catalyst, although acrylonitrile is generally not easy for hydrosilylation. After introducing tiny amounts of cyano (-C≡N) groups into the PCS molecules, the ceramic yield of PCSCN can increase largely to over 80 %. The ceramization mechanism of PCSCN is investigated by FTIR, TG, XPS , ESR , NMR, Raman and XRD analyses. It is found that some crosslinking structures in PCSCN are formed between Si H bonds and C N groups from about 200 ℃, which can be responsible for the high ceramic yield. The existence of a little more N, O and free C elements in the pyrolysis products may inhibit the growth of crystalline β-SiC. Moreover, the PCSCN precursor can also be melt-spun into continuous fibers by tailoring its molecular weight and softening point. The oxidized PCSCN fiber with relatively low oxygen content can be pyrolyzed without melting, and the final SiC fiber with an oxygen content as low as 8.5 % is obtained.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 18
·1-13
·
IF 2.8
Li Chaojie,Feng Yonghang,Cui Yi,Zhang Fan,Lv Dongfeng,Liu Pan,Wei Yingna,Wei Hengyong,Bu Jinglong
The NiCo 2 O 4 nanoflakes/SiC fibers composites were prepared by electrospinning, carbon thermal reduction combined with hydrothermal method. The results of SEM, XRD and XPS suggested that the NiCo 2 O 4 nanoflakes/SiC fibers composites were successfully prepared. The NiCo 2 O 4 nanoflakes were generated on the surface of SiC fibers with uniform distribution and loose structure. The NiCo 2 O 4 nanoflakes/SiC fibers composites possess the porous structure and their BET specific surface area is 233.2 m 2 /g. The BJH average pore size and the pore volume are 7.0 nm and 0.4 cm 3 /g, respectively. The structure of fibers and pores can bring the multiple reflections and scatterings, interface polarizations, dipole polarizations and conductivity losses. In addition, there is the synergistic effect of dielectric loss and the magnetic loss in NiCo 2 O 4 nanoflakes/SiC fibers composites. Therefore, the reflection loss of NiCo 2 O 4 nanoflakes/SiC fibers composites could achieve − 56 dB under the thickness of 6 mm at 17.64 GHz, which showed the better microwave absorption behavior than SiC fibers.
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
·
2025
·
IF 5.6
Linying Huang,Hui Wang,Qin Ouyang,Gaoming Mo,Jing Huang,Yueqing Zheng,Qing Huang
Polymer-derived silicon carbide (SiC) fibers are excellent structural and functional materials for extreme environments. However, the low efficiency of the curing process and the inferior stability of the amorphous SiC x O y phase have limited their large-scale preparation and widespread application. In this study, phenylboronic acid (PBA)-modified polyaluminocarbosilane (PACS) electrospun fibers were cured efficiently via an electron beam irradiation oxidation technique, and then converted into highly crystalline SiC fibers with low oxygen content by high-temperature sintering. The combination of irradiation oxidation and subsequent annealing treatment facilitated the effective, rapid, and sufficient curing of PACS fibers. Notably, boron played a significant role in inhibiting the growth of SiC grains and promoting the graphitization of free carbon. The SiC fibers obtained from PBA-modified PACS through irradiation oxidation curing exhibited superior electrical conductivity and microwave absorption performance, achieving a minimal reflection loss (RL) of −41.8 dB at 12 GHz with a thickness of 1.5 mm. This work provides an effective method for preparing SiC fibers with tunable carbon structures and enhanced microwave absorption properties, thereby paving a way for expanding their applications.
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
危险品化学品经营许可证（带存储）