JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2021
·Vol. 32
·期 21
·25895-25907
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IF 2.478
Liu Xiaoling,Tang Zhiming,Xue Jimei,Wei Hanjun,Fan Xiaomeng,Liu Yongsheng,Cheng Laifei
Porous SiCN(Ti) composite ceramics with good microwave absorbing performance were fabricated by pyrolysis of solid polysilazane modified by tetrabutyl titanate. The introduction of Ti not only acted as active filler to react with free carbon in the matrix to form TiC, but also played the role as catalyst to promote the formation of SiC nanowires. Finally, SiCN(Ti) composite ceramics formed a microstructure containing multi-nanophases and multi-nano heterogeneous interfaces when annealing temperature reached 1500 °C. The complex microstructure annealed at 1500 °C made composite ceramics have good matching impedance, as well as greatly increase the interfacial polarization loss and dipole polarization loss. As a result, the TiC/SiC/SiCN composite ceramics showed the excellent performance of electromagnetic wave absorption in X band. The minimum reflection loss (RL) of samples was − 17.1 dB at the thickness of 1.9 mm, and the maximum effective absorption bandwidth (EAB) of composite ceramics was 3.2 GHz when the thickness of sample was 2.1 mm, which exhibited a promising prospect as a structural and microwave absorbing integration material.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Shuai Wang,Yangyang Deng,Mingsheng Yang,Luyao Wang,Huaiqian Li,Pengfei Xing
Dense B 4 C–SiC–CrB 2 ternary composites were fabricated via reactive hot pressing with B 4 C and chromic silicides (84 wt% CrSi 2 +16 wt% CrSi) as raw materials. The effects of chromic silicides on the densification, phase components, microstructure and performance of the prepared composites were investigated. The reaction mechanism and toughening mechanism were also studied. The results indicated that the chromic silicides were the reactive sintering aids which reacted with B 4 C and C to introduce CrB 2 and SiC in the matrix in situ. Partial B 4 C, CrB 2 and SiC formed the eutectic liquid phase, which enhanced the densification of B 4 C. The addition of chromic silicides enhanced the densification and fracture toughness while reduced the hardness. The good comprehensive performances of 435 MPa flexural strength , 4.09 MPa m 1/2 fracture toughness and 33.11 GPa hardness were obtained in the composites fabricated with 10 wt% chromic silicides. The higher addition amounts of chromic silicides resulted in the larger-size SiC, which reduced the flexural strength. The transgranular fracture of SiC and partial CrB 2 , the existing phenomena such as microcracks , crack branching and crack deflection could cumulatively improve the fracture toughness of the materials.
研究领域:
材料科学
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陶瓷学
✓ 已验证
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
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2021
·
IF 6.141
Yuan Fang,Aoxuan Wang,Keze He,Hongying Pan,Jiajun Liao,Zhu Ding,Feng Xing,Huirong Le,Xianfeng Wang
This article investigates the key interface properties of geopolymers reinforced by SiC whiskers loaded with BN coating (BN/SiCw) and the insight of mechanical performance and microstructures of the resulting composites. The interesting diverse strength evolutions of geopolymer composites calcinated at various temperatures suggest a result of rivalries of multiple factors including BN coating, geopolymer matrix transformations, SiC whiskers. A positive effect on whisker pull-out phenomenon has been achieved via the chemical bonding between SiC whisker (SiCw) and BN coating and the rough physical interface between BN coating and geopolymers; the addition of SiCw and BN/SiCw promotes the polycondensation reaction of geopolymers and the addition of the latter is superior. Through changing the pore structure characteristics of the composites, the SiCw in composites can release their excessive vapor pressure in the closed pores which is the main reason attributing to the strength loss of geopolymers at 900 °C. In addition, BN coating can make up for the mismatch of thermal expansion coefficient between SiCw and geopolymers, increasing the strength of the composites by 30.9% at 900 °C, whereas whisker pull-out and crack deflection are the main toughening effect for BN/SiCw.
研究领域:
材料科学
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工程学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2015
·
IF 2.947
Rong Tu,Nian Li,Qizhong Li,Song Zhang,Lianmeng Zhang,Takashi Goto
In order to improve the hardness and toughness simultaneously, B 4 C–HfB 2 –SiC ternary composites were synthesized by arc-melting using B 4 C, HfB 2 and β-SiC powders as raw materials. The ternary eutectic composition of 45B 4 C–15HfB 2 –40SiC (mol%) was first identified with a lamellar eutectic texture. HfB 2 about 500 nm in thickness and SiC about 700 nm in thickness were uniformly dispersed in B 4 C matrix of the eutectic composite, much smaller than raw powders. The Vickers hardness and fracture toughness of B 4 C–HfB 2 –SiC ternary eutectic were 35.7 GPa and 6.5 MPa m 1/2 at the eutectic composition, respectively.
研究领域:
材料科学
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复合材料
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陶瓷材料
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高温材料
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力学性能
✓ 已验证
DOI
高影响因子
Energy Technology
·
2019
·Vol. 7
·期 7
·1900017
·
IF 3.163
Zhongyi Du,Pengju Sun,Kuanhuai Wu,Xiarong Zheng,Xingfeng Zhang,Jiale Huang,Daohua Sun,Yanmei Zheng,Qingbiao Li
Graphite carbon nitride (g-C 3 N 4 ) and SiC have drawn increasing attention for application in visible light photocatalytic hydrogen evolution by water splitting due to their unique band structure and high physicochemical stability. Herein, a g-C 3 N 4 -SiC heterojunction with loaded noble metal is constructed. The g-C 3 N 4 -SiC-Pt composite photocatalysts are successfully prepared by the combination method of bio-reduction, sol deposition, and calcination. The layers of g-C 3 N 4 are thinned, and both SiC and Pt nanoparticles are simultaneously tightly bound to g-C 3 N 4 by calcination during the preparation of g-C 3 N 4 -SiC-Pt. The heterojunction formed at the interface of SiC and g-C 3 N 4 enhances the separation efficiency of the photogenerated electron–hole pairs. These composite photocatalysts achieve a high hydrogen evolution rate of 595.3 μmol h −1 g −1 with 1 wt% of deposited Pt, which is 3.7- and 2.07-fold higher than those of g-C 3 N 4 -bulk and g-C 3 N 4 -SiC under visible light irradiation with a quantum efficiency of 2.76% at 420 nm, respectively.
研究领域:
材料科学
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能源化学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Shang Gao,Boyu Hu,Xin Song,Zhigang Dong,Renke Kang
Chemical mechanical polishing (CMP) offers promising pathway to smooth 4H-SiC. Dispersion stability of polishing slurry is crucial factor affecting 4H-SiC performance. Particles in polishing slurry can easily agglomerate due to poor dispersion stability, affecting surface quality of wafers. Nano-Al 2 O 3 is common particle in the slurry that directly controls mechanical removal. In this paper, the impact of different dispersants (PEG, (NaPO 3 ) 6 , and NH 4 PAA) on the dispersibility of slurry containing nano-Al 2 O 3 is studied. Results indicate that the slurry containing NH 4 PAA exhibits the greatest dispersion stability with superior 4H-SiC surface quality, with surface roughness (Sa) reaching 1.054 nm. The slurry containing PEG shows poor dispersion, leading to poor SiC surface quality, and the Sa reached 5.314 nm. The dispersion mechanism of different dispersants is also discussed.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Zahoor Ahmad,Jianjun Chen,Xiaohong Li,Hao Chen,Hafsa,Muhammad Arfan,Zaheer Hussain
SiC fiber-reinforced SiC ceramic matrix composites (SiC f /SiC CMCs) hold potential as thermal structural materials. In this work, SiC nanofibres were coated with multilayer interfaces by magnetron sputtering with the aim to tailor the fiber-matrix interface of SiC nanofibre reinforced SiC composites for superior mechanical properties. The influence of multilayer interface coating and sintering temperature on the density, microstructure, and mechanical properties of SiC nf /SiC CMCs fabricated via a hot-press technique employing ultra-long single-crystal SiC nanofibers as reinforcement were investigated. The composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and a universal testing machine. The prepared CMCs were toughened and strengthened by the observed fiber pull-out and bridging. The multilayered SiC nf /SiC CMCs with multiple interface coatings display an identifiable saw-tooth-like pattern in the load-displacement test, suggesting a significant improvement in the toughness of prepared materials through a laminated structure with weaker interface binding brought on by the thicker, denser coating. In comparison to the SiC nf /SiC composites without interface coating, the prepared SiC nf /SiC CMCs with PyC/SiAlC/ZrC interface layers revealed optimum flexural strength (520 ± 28.88 MPa, ↑46.5 %) and fracture toughness (9.95 ± 0.44 MPa m 1/2 , ↑94.7 %) after an hour of hot pressing at 1800 °C under pressure of 30 MPa. Besides an increase in relative density at high sintering temperatures (1850 °C), further grain coarsening deteriorated mechanical properties.
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
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Meng Liu,Yong Yang,Yuquan Wei,Yajie Li,Heng Zhang,Xuejian Liu,Zhengren Huang
High-purity SiC materials have been used in semiconductor processes due to their excellent properties. However, they are difficult to densify without sintering aids. In this work, dense and high-purity SiC ceramics have been obtained by pressureless solid-state-sintering with ultra-low contents of sintering additives. The amount of residual B, C and O in the high-purity SiC ceramics was less than 0.15 wt%, respectively, and the total content of other impurity elements (such as aluminum , magnesium, calcium, iron, etc.) was less than 0.015 wt%. Finally, the purity of the as-prepared SiC ceramics was more than 99.5 wt%.
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
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2022
·
IF 6.364
Qingyi Kong,Sijia Huo,Lei Chen,Yujin Wang,Jiahu Ouyang,Yu Zhou
Fully dense (Zr, Ti)B 2 -(Zr, Ti)C-SiC ceramics were prepared by reactive hot-pressing using ZrB 2 , TiC, and SiC as the initial materials for the first time. Effects of SiC addition on the microstructure evolution and mechanical properties were reported. The in-situ reaction between ZrB 2 and TiC as well as the SiC addition leads to the grain refinement. Besides, elongated (Zr, Ti)B 2 plate-like grains are obtained due to the occurrence of a transient liquid phase, which leads to the crack deflection in the matrix effectively. Mechanical properties are improved significantly due to grain-refinement and solid solution strengthening, and plate-like grains toughening effects. The ZrB 2 -10 mol%TiC composite with 10 mol% SiC additional exhibits good comprehensive mechanical properties of the hardness of 20.2 GPa, the flexural strength of 803 MPa, and the fracture toughness of 5.7 MPa m 1/2 .
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
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Mengting Jiang,Liwen He,Chao Duan,Xiaoping Ouyang
Poor fracture toughness is a major limitation of SiC ceramics, which greatly affects their application range. Herein, a novel strategy is proposed to enhance the fracture toughness of SiC ceramics by cross-linking carbon nanotubes (CNTs) coated with polydopamine (PDA) to Ti 3 C 2 modified with 3-glycidyloxypropyltrime-thoxysilane (KH560) (PDA-CNTs@f-Ti 3 C 2 ). Then, PDA-CNTs@f-Ti 3 C 2 was added to SiC powder to prepare the final composite. The influence of PDA-CNTs@f-Ti 3 C 2 addition on the microstructure and mechanical properties of the SiC composite is discussed. The results showed that, compared with CNTs and Ti 3 C 2 , the PDA-CNTs@f-Ti 3 C 2 composites exhibited better dispersibility in water. The flexural strength was significantly enhanced (~89%) in the SiC composite containing 3 wt% PDA-CNTs@f-Ti 3 C 2 , from 228.99 MPa to 433.55 MPa. The fracture toughness of the SiC composite containing 3 wt% PDA-CNTs@f-Ti 3 C 2 improved by 62%, from 3.97 MPa/m 1/2 to 6.44 MPa/m 1/2 .
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
CARBON
·
2024
·
IF 10.5
Bohan Wang,Fei Li,Shuo Zhao,Binbin Fan,Dengke Zhao,Shijia Zhang,Yiyao Ge,Jie Zhang,Wenbin Cao,Kexin Chen,Guanghua Liu
Economical and green preparation of SiC composites with tunable microwave-absorbing properties is crucial for industrial applications. In this study, SiC/graphene nanocomposites were synthesized via combustion synthesis technology by using CO 2 , a greenhouse gas, as the carbon source. The phase composition, microstructure and microwave-absorbing performance of the SiC/graphene nanocomposites were characterized. Dielectric properties and impedance matching can be precisely controlled simultaneously by changing the composition of the SiC/graphene nanocomposites. The characteristic microstructure of the SiC/graphene nanocomposites with networks of multilayer graphene sheets has a significant contribution to the improved microwave attenuation capability. The SiC/graphene nanocomposite sample with optimized composition and microstructure showed excellent microwave-absorbing performance, with a reflection loss (RL) of −63.94 dB at 6.15 GHz, and effective absorption bandwidth (EAB) of 4.05 GHz for RL < −10 dB. The SiC/graphene nanocomposites with strong microwave absorption have great potential for applications prospects in various fields.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）