MATERIALS CHEMISTRY AND PHYSICS
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2024
·
IF 4.3
Yonghui Yu,Jie Wei,Xianghui Yan,Yuhong Chen,Biao Zhang,Yujin Wang,Feng Ye,Limeng Liu
TaB 2 –SiC composites with 0–20 wt% SiC contents were prepared by reaction hot pressing using Ta, B and SiC powders as starting materials. Densification, constituent phases, microstructure and mechanical properties, namely Vickers hardness, fracture toughness and flexure strength, were evaluated by means of inspection of sintering shrinkage, density measurement, XRD, SEM, TEM, HRTEM, EDS, SAED, indentation and three-point bending tests. Phase formation, including dominant (TaB 2 , SiC) and minor (TaC, glassy SiO 2 ) phases, was checked by thermodynamic assessment relevant with Ta 2 O 5 and B 2 O 3 impurities introduced into the reaction system by the starting powders. The results showed that mixtures of Ta, B and SiC powders would initiate self-propagating combustion synthesis (SPCS) at about 900 °C; a transient hold at 800 °C for 1 h could suppress this reaction. Volatilization of B 2 O 3 impurity in association with local high temperature due to SPCS helped reduce the TaC and glassy SiO 2 minor phase formation. TaB 2 –SiC composites could reach 99 % relative densities with 3 wt% SiC addition and above. Compositions with <7.5 wt% SiC additions showed uniform dispersion of SiC particles at multi-TaB 2 grain junctions while compositions with higher SiC content revealed SiC segregation. Bending strength of 503 MPa and fracture toughness of 6.69 MPa⋅m 1/2 could be reached with 7.5–20 wt% SiC addition.
研究领域:
材料科学
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机械工程
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yang Liu,Jin-Hao Yuan,Hou-Liang Tian,Wei-Ming Guo,Shi-Kuan Sun,Xiao-Ming Duan,De-Chang Jia,Hua-Tay Lin
Spark plasma sintered SiC-based ceramics with amorphous Y 2 O 3 –Al 2 O 3 –SiO 2 and CaO–Al 2 O 3 sintering additives prepared by melt-quench approach, were compared with those with the direct addition of raw Y 2 O 3 –Al 2 O 3 –SiO 2 and CaO–Al 2 O 3 mixture. The relative densities of SiC-based with raw Y 2 O 3 –Al 2 O 3 –SiO 2 and CaO–Al 2 O 3 were 95.3% and 94.3%, respectively. In spite of the same composition of sintering additive, the relative densities of SiC-based ceramics reached the values of 98.9% and 99.5% by using the glassy additives of Y 2 O 3 –Al 2 O 3 –SiO 2 and CaO–Al 2 O 3 , respectively, and the hardness of SiC-based ceramics was improved by about 22.2% and 17.2%, respectively. The amorphous sintering additive effectively improved the densification and hardness of SiC ceramics.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2024
·
IF 5.8
Jianan Shan,Gaoming Mo,Qing Sun,Jing Huang,Qin Ouyang,Qing Huang
SiC fiber is an important structural material in high-temperature extreme environments and nuclear energy applications. Oxidation and electron irradiation are main curing methods for the fabrication of industrial SiC fibers. In this work, a photo-sensitive polyvinylaluminocarbosilane (PVACS) is facilely prepared by blending polyaluminocarbosilane (PACS) and 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane (D4Vi), which can be melt spun, cured by ultraviolet irradiation at room temperature. After thermal pyrolysis and sintering, the SiC(OAl) fibers with oxygen content of 8.84 wt% and C/Si ratio of 1.34, the SiC(Al) fibers with oxygen content of 0.29 wt% and C/Si ratio of 1.03 are achieved. The cured mechanism and the structural evolution from the precursor fiber to the final ceramic fibers is investigated. The results show that homopolymerization of D4Vi is the main curing mechanism in addition to the β-addition of hydrosilylation. Different from the typical oxidative curing, the oxygen in the fibers mainly comes from D4Vi. At about 800 ℃, the SiAl x O y phase, the SiC x O y phase and free carbon are formed. At 1200 ℃, the Al-C bonds possibly in Al 4 C 3 are formed. At around 1600 ℃, Al may exist mainly in the form of Al 4 O 4 C, and the amorphous carbon phase changes into crystalline graphitic structure. Meanwhile, a lot of mesopores and macropores in the SiC(OAl) fibers are formed due to thermal decomposition of the SiC x O y phase. However, at 1800 ℃, the SiC(Al) fibers densify again due to the formation of Al 2 OC and Al 4 SiC 4 phases, which also inhibit the growth of β-SiC and favor the formation of α-SiC.
研究领域:
材料科学
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无机化学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 20
·10999-11005
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IF 7.443
Xunfu Zhou,Qiongzhi Gao,Xin Li,Yingju Liu,Shengsen Zhang,Yueping Fang,Jun Li
Herein, for the first time, ultra-thin SiC nanoparticles or ultra-thin layer covered graphene nanosheets were successfully prepared via using a facile in situ vapor–solid reaction. The samples were characterized by X-ray diffraction, UV-visible spectroscopy, photoluminescence spectra analysis, Raman spectra, transient photocurrent responses and transmission electron microscopy. The photocatalytic activities were also evaluated by H2 evolution from pure water or water containing Na2S as an electron donor. The resulting SiC–graphene hybrids show enhanced photocatalytic H2-evolution activities in the presence of an electron donor. Especially, the graphene nanosheet and SiC nanocrystal hybrids show the highest photocatalytic activity in H2 production under visible light, which is about 10 times higher than that of the SiC nanocrystals. The enhanced activities of the SiC–graphene hybrids can be attributed to their 2D nanosheet structures, large surface area, enhanced visible-light absorption and rapid interfacial charge transfer from SiC to graphene. Our results can provide an effective approach to synthesize graphene-based heterogeneous nanocomposites for a wide variety of potential applications in solar energy conversion and storage, separation, and purification processes.
研究领域:
材料科学
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能源化学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
·
IF 4.495
Yehong Cheng,Yaxiong Liu,Yumin An,Ning Hu
Graphene derivative materials exhibit excellent mechanical and thermal properties, which have been extensively used to toughen ceramics and improve thermal shock resistance . To overcome the thermal agglomeration of graphene oxide (GO) during heating and drying process, ZrB 2 -SiC particles decorated GO hybrid foam with uniformly anchored ceramic particles was synthesized by electrostatic self-assembly and liquid nitrogen-assisted freeze-drying process. Densified rGO/ZrB 2 -SiC ceramics with varying microstructure, thermal physical and mechanical properties were obtained by adjusting the content of decorated ceramic particles. Although the flexural strength of rGO/ZrB 2 -SiC ceramics have an attenuation compared with that of ZrB 2 -SiC ceramic, the thermal conductivity , work of fracture and thermal shock resistance are greatly improved. rGO/ZrB 2 -SiC ceramics exhibit delayed fracture and increasing R-curve behavior during the crack propagation . The novel preparation technology allows for the well dispersion of rGO in ZrB 2 -SiC ceramics and can be easily extended to other ceramic or metal materials systems.
研究领域:
材料科学
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工程学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Tianxiang Hong,Yuhong Chen,Ruibin Liu,Wanxiu Hai,Xiuling Zhang,Meiling Liu,Shuo Yan
Diamond/SiC composites with SiC matrix were prepared by using a liquid silicon infiltration method. The interface morphology and thermal conductivity of the composites have been analyzed by scanning electron microscopy (SEM), and a laser flash thermal conductivity test, respectively. The thermal resistance of the interface structures has been calculated by using the acoustic and diffusion mismatch models. After the addition of mono-sized SiC particles, an increased diamond content resulted in an increased thermal conductivity of the composites. After the addition of SiC with a graded mix-sized particle under fixed diamond content condition, although the residual Si content decreased, the thermal conductivity of the composites showed little changes. Furthermore, the thermal conductivity of the composites have been calculated by applying Cubic Structure (C-S) and Hasselman-Johnson (H-J) models. The result shows that the calculations based on the C-S model showed the best agreement with the experimental thermal conductivity of the experiments with the addition of mono-sized SiC particles compared to the results analyzed by the other calculation models. The calculations based on the H-J model showed the best agreement with the experimental thermal conductivity of the graded mix-sized SiC particles composites compared to results analyzed by the other calculation models.
研究领域:
材料科学
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热物理学
✓ 已验证
DOI
高影响因子
APPLIED ENERGY
·
2022
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IF 11.446
Boshu Jiang,Bachirou Guene Lougou,Hao Zhang,Boxi Geng,Lianxuan Wu,Yong Shuai
The solar-driven thermochemical CO 2 -to-CO conversion is an effective way to achieve the mission of carbon peaking and carbon neutrality. However, synthesizing porous reacting materials with excellent thermal stability, hardness and long-term cyclic stability, oxygen exchange capacity, and higher CO 2 -to-CO conversion are the most important challenges associated with the thermochemical CO 2 -splitting approach and technological upscaling to large-scale applications. This study presented the development of NiFe 2 O 4 oxygen carriers, the synthesis method of SiC and Si 3 N 4 supports, and solar-to-fuel processing of the newly prepared materials through CO 2 -splitting under a highly concentrated solar radiative heat flux. The newly synthesized NiFe 2 O 4 @SiC porous redox material resulted in higher solar energy absorption and CO 2 conversion capability with an instantaneous CO production of 410 μmol/g and direct CO 2 -to-CO conversion rate of 18.1 % at 1073–1273 K reaction temperature. The media composite of NiFe 2 O 4 @SiC exhibited high-temperature thermal changes, good thermochemical reaction stability, and a higher CO production rate through six redox cycles compared to NiFe 2 O 4 @Si 3 N 4 porous reacting material. The high oxidation potential and remarkably solar radiative heat flux absorption and thermochemical CO 2 -splitting capacities of the newly developed materials were demonstrated through experimental analysis. The synergistic effect of the oxygen carriers (NiFe 2 O 4 ) and substrate materials including SiC and Si 3 N 4 skeletons for CO 2 -splitting is highlighted. This study provided comprehensive and novel experimental insights that can be used as guidance for theoretical research and application in CO 2 conversion into high-value-added energy products.
研究领域:
材料科学
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可再生能源
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2018
·
IF 3.794
Yehong Cheng,Ping Hu,Shanbao Zhou,Xinghong Zhang,Wenbo Han
Graphene is one of the important candidates in ceramic toughening due to its outstanding physical and chemical properties. For the weak interface toughening of large-diameter graphene sheet and alleviation of the interfacial reaction between ceramic precursors and graphene sheets during high-temperature pyrolysis, ZrC–SiC‒Graphene composite was synthesized via a facile technology of infiltrating ceramic slurry instead of ceramic precursor into macroporous graphene network and spark plasma sintering . The incorporation of the graphene network improved fracture toughness, critical crack size, and fracture energy of ZrC–SiC ceramic. The multiple length-scale toughening mechanisms of ZrC–SiC‒Graphene composite include the macroscopic toughening mechanism of crack deflection and bifurcation and the micro toughening mechanism of graphene bridging, ceramic micro zone tearing, graphene pull-out, graphene and ceramic brick slipping.
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
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 7
·1-8
·
IF 6.232
Yao Wenyan,Shi Jian,Ling Jiang,Guo Yadong,Ding Chensen,Ding Yanjun
Aptamer-modified SiC quantum dots (DNA-SiC QDs) as fluorescent aptasensor are described for the determination of Proteus mirabilis . The SiC QDs were synthesized through one-pot hydrothermal method with particle sizes of about 14 nm. The amino-modified aptamers against P. mirabilis were conjugated to the surfaces of SiC QDs for bacteria recognition . The aptamer with an affinity for target protein can bound to P. mirabilis and this causes a decrease in the fluorescence intensity of DNA-SiC QDs. P. mirabilis levels were tested by the aptasensor within 35 min with fluorescence excitation/emission maxima at 320/420 nm. The linear range is from 10 3 to 10 8 CFU mL −1 and the limit of detection is 526 CFU mL −1 ( S / N = 3). The aptasensor was used for determination of P. mirabilis in pure milk samples and obtained good accuracy (87.6–104.5%) and recovery rates (85–110.2%) were obtained. The detection in simulated forensic identification samples (pure milk, milk powder, blood, and urine) obtained gave satisfactory coincidence rates with the method of bacterial isolation and identification as standard. These results demonstrate that the fluorescent aptasensor is a potential tool for identification of P. mirabilis in forensic food poisoning cases.
Determination of P. mirabilis is based on SiC QDs fluorescence aptasensor. The SiC QDs with plentiful carboxyl groups on the surface can be synthesized via one-pot hydrothermal route. After activated by EDC/NHS, the SiC QDs can bind to aptamer to form fluorescence aptasensors. When the target P. mirabilis exists, the fluorescence of aptasensor will be quenched and the determination of the P. mirabilis based on the fluorescence change can be analyzed.
研究领域:
生物传感技术
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微生物学
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食品安全检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2016
·
IF 2.933
Xiaorong Zhang,Zhixiao Zhang,Weimin Wang,Xiaoliang Zhang,Jingbo Mu,Guangsuo Wang,Zhengyi Fu
High-performance B 4 C composites toughened by TiB 2 -SiC agglomerates were fabricated via reactive hot pressing with B 4 C, TiC and Si as raw materials. The TiB 2 -SiC composite serves as a composite toughening phase formed in the B 4 C matrix through an in situ reaction; its agglomerates are composed of interlocked TiB 2 and SiC, which can remarkably improve the toughness of the B 4 C composites. The Vickers hardness , flexural strength and fracture toughness of the B 4 C-TiB 2 -SiC composite reached 35.18 ± 0.45 GPa, 567 ± 14 MPa, and 6.38 ± 0.18 MPa m 1/2 respectively. The special toughening structure of the TiB 2 -SiC composite introduced into B 4 C ceramics was evaluated for the first time in this study.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2022
·Vol. 19
·期 4
·1956-1969
·
IF 2.328
Wanbo Hou,Wei Qi,Yongqiang Yang,Tao Feng,Mingyu Liang,Mingde Tong,Hejun Li,Hongjiao Lin,Shifeng Wen
The slurry and sol-gel methods were used to introduce SiC nanowires (SiC nws ) into the SiC f /HfC-SiC composites. The microstructures, ablation, and bending behaviors of the SiC nws modified composites prepared by the two methods were compared. The bending strengths of the modified composites obtained by introducing SiC nws by the slurry and sol-gel methods were 224 ± 19 and 154 ± 14 MPa, respectively. The results showed that SiC fibers with chemical corrosion and thermal damage during the sol-gel process decreased the bending strength of the SiC nws -modified SiC f /HfC-SiC composites. Meanwhile, the pyrolytic carbon interface accompanying corrosion damage in the sol-gel process led to the degradation of interface function, which hindered the interface debonding and fiber sliding of the composites during the bending test. After ablation, the bending strengths of the two composites were 188 ± 19 and 50 ± 7 MPa, respectively. The bending strength retention of the modified composites fabricated by the slurry method (83.9%) was higher than that (32.5%) of the composites fabricated by the sol-gel method after ablation. As the composites fabricated by the slurry method exhibited a good ablation resistance under the oxyacetylene flame (∼2350°C).
研究领域:
材料科学
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航空航天工程
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2020
·Vol. 7
·期 1
·016438
·
IF 1.929
Yong Lian,Xianyi Dai,Jin Zhang
In the present work, particles of SiC were applied to the micro-arc oxidation (MAO) treatment of Ti6Al4V, characterization of MAO coatings with different SiC particle concentration were evaluated. X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) results show that the structure and morphology of MAO ceramic coatings could change with different amounts of SiC in the electrolyte. Both of the number and size of the pores on the ceramic coating surface were decreased, while the layer thickness increased with the increase in SiC particles in the electrolyte. A dense double-layer structure coating composed of a Ti-based layer and a SiC-based layer with a thickness of about 40 μm was prepared. It was shown that the addition of SiC particles participated in the process of micro-arc oxidation and changed the microstructure of MAO coating.
研究领域:
材料科学
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表面工程
✓ 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）