Journal of Advanced Ceramics
·
2019
·Vol. 8
·期 4
·527-536
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IF 2.3
Zhang Zhaofu,Sha Jianjun,Zu Yufei,Dai Jixiang,Liu Yingjun
Self-toughening ZrB 2 –SiC based composites are fabricated by in-situ reactive hot pressing. The effect of sintering additive content on the microstructure and mechanical properties of the composites is investigated. Microstructure observation found that the in-situ reactive hot pressing could promote the anisotropic growth of ZrB 2 grains and the formation of interlocking microstructure. Such microstructure could improve the mechanical properties, especially, for the fracture toughness. The improved mechanical properties could be attributed to the self-toughening structure related to the ZrB 2 platelets and the formed interlocking microstructure, which could trigger various toughening mechanisms such as grain pull-out, crack bridging, crack deflection, and crack branching, providing the main contribution to the high fracture toughness.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2013
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IF 1.858
Rubing Zhang,Rujie He,Xinghong Zhang,Daining Fang
ZrB 2 –SiC ceramic composites were prepared through water-based gelcasting and pressureless sintering. Effects of the pressureless sintering temperature (1500–2000 °C), heating rate (5–15 °C/min) and soaking time (0.5–2 h) on the relative density, microstructure and mechanical properties of the ZrB 2 –SiC composites were investigated in detail. A sintering temperature of 2000 °C, a heating rate of 5 °C/min and a soaking time of 2 h were found to be the optimal pressureless sintering procedure. The relative density, flexural strength and fracture toughness of the ZrB 2 –SiC composite prepared under the optimum condition were 97.8%, 403.1 ± 27.8 MPa and 4.05 ± 0.42 MPa·m 1/2 , respectively.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
DOI
高影响因子
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
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 15
·e202400724
·
IF 1.9
Zekai Zhang,Ding Zhang,Stéphane Abanades,Hanfeng Lu
Graphical A strategy to use high-temperature semiconductor photocatalyst dealing with artificial photosynthesis for CO 2 photothermal reduction with concentrated sunlight was proposed. A CuO/SiC catalyst was accordingly designed and showed extremely high CO 2 photoreduction activity with H 2 O at high temperature. The CH 4 yield reached 2041 μmol ⋅ g −1 at 350 °C with maximum solar energy conversion efficiency of 2.3 %. Artificial photosynthesis can convert CO 2 and H 2 O into hydrocarbons via solar energy. However, the extremely low process efficiency is a major obstacle to this application. The photocatalyst is considered to be the key factor to raise the overall solar energy conversion efficiency. Much research focused on co-catalysts, but less attention has been paid on the high-temperature semiconductor. Herein, a strategy is proposed involving high-temperature semiconductor to design target photocatalyst dealing with the artificial photosynthesis at high temperature. Based upon this strategy, a CuO/SiC catalyst with single atom characteristic was designed, prepared and the activity of CO 2 photoreduction with H 2 O was tested in a high temperature environment. Above 150 °C, the catalyst activity was boosted and unprecedented performance values were attained. Under the irradiation condition delivered by a 1000 W Xe light and at 350 °C, the obtained yields of CH 4 , C 2 H 4 , and C 2 H 6 were 2041.4 μmol ⋅ g −1 , 15.2 μmol ⋅ g −1 , and 63.6 μmol ⋅ g −1 , respectively. The overall CO 2 conversion reached 24.6 % and the maximum solar energy conversion efficiency was 2.3 % without any sacrificed agents. This strategy will be helpful to overcome the current limitations for the industrialization of artificial photosynthesis and accelerate the related research on photothermal catalysis.
研究领域:
化学
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能源科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Wei Ding,Pengjian Lu,Qingfang Xu,Chitengfei Zhang,Rong Tu,Song Zhang
In the integrated circuit industry, heat is transferred through the contact between wafers and the chemical vapor deposited (CVD) 3C–SiC wafer susceptor . Understanding the out-plane thermal conductivity of CVD 3C–SiC is crucial in this context. The influence of grain size and grain boundary characteristics on out-plane thermal conductivity for <111>-oriented CVD 3C–SiC was discussed in this study. The out-plane thermal conductivity sharply decreases from 146.4 W/m⸱K to 122.3 W/m⸱K when the grain size approaches 11.04 μm. This paper suggests that the significant accumulation of dislocations at high-angle grain boundaries is the primary cause of this phenomenon. The substantial lattice strain impedes phonon transfer between grain boundaries, reducing overall phonon mobility. These findings suggest that manipulating the grain boundary angle is an effective means to fine-tune heat transfer in <111>-oriented CVD 3C–SiC.
研究领域:
材料科学
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热物理学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Qianglong He,Jingjing Xie,Aiyang Wang,Chun Liu,Tian Tian,Lanxin Hu,Chenhong Yi,Zhixiao Zhang,Hao Wang,Weimin Wang,Zhengyi Fu
B x C-TiB 2 -SiC ceramic composites were fabricated via reactive hot pressing using TiC, B, and Si as the raw materials. The phase transition process was studied by heating powder mixtures to different temperatures in combination with X-ray diffraction analysis. The stoichiometric ratio between B and C in boron carbide is variable. A series of powder mixtures containing excess boron (0 wt%, 10 wt%, 20 wt%, or 30 wt% B) were sintered, and the microstructures and mechanical properties of the composites were investigated. The results showed that the B 6.1 C-TiB 2 -SiC composite prepared from the starting powders with 30 wt% excess boron had the best comprehensive mechanical properties , with a relative density, hardness, bending strength , and fracture toughness of 98.32%, 33.2 GPa, 840 MPa, and 5.22 MPa m 1/2 , respectively. Excessive boron substitution may cause lattice distortion in boron carbide , and the boron carbide grains in this state may form a large number of twins under the compressive stress generated by the TiB 2 grains, which will affect the properties of the composites.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
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2024
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IF 6.1
Qiang Liu,Jiarui Yang,Guoqing Tian,Zhenhui Huang,Liying Shen,Chuyan Hu,Baihan Wang,Kaiyang Wang,Shuang Feng,Feng Ye
Materials with high specific strength and toughness are urgently needed in the fields of electronic packaging, armor, and aerospace. SiC/Al composites show good potential for these applications but the problem of mutual exclusion of strength and toughness still needs to be solved. Herein, we propose a new strategy to simultaneously enhance its strength and toughness from the perspective of structural optimization and interface enhancement. Inspired by the nacre structure, a 3D-(SiC–Si 3 N 4 )/Al co-continuous composite was prepared by freeze-casting combined with the pressure infiltration method. During the process, elongated Si 3 N 4 grains were introduced into the ceramic framework to design the internal lamella wall structure and increase the contact area with the aluminum substrate. Moreover, a favorable interfacial bonding was designed between Si 3 N 4 and Al to improve interface wettability . The reliable microstructure of porous 3D-(SiC–Si 3 N 4 ) preform was tailored through the adjustment of initial solid loading and the α-Si 3 N 4 component. The effects of initial solid loading and the α-Si 3 N 4 component on the microstructure, interfacial wettability, and mechanical properties of the final composites were investigated. The results showed that the SiC–Si 3 N 4 /Al composites possess high flexural strength (769 MPa) and fracture toughness (15.1 MPa m 1/2 ), which is superior to data reported in general literature. Numerous elongated β-Si 3 N 4 grains are produced on the ceramic skeleton, forming an interlocking structure with the aluminum matrix, which increases the contact area with the aluminum substrate. A chemical reaction layer was formed at the interface of the composite, greatly improving the interfacial bonding strength. This work provides a promising design guideline for developing and optimizing high-strength and tough composite.
研究领域:
材料科学
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复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2016
·
IF 1.34
Dong HUANG,Ming-yu ZHANG,Qi-zhong HUANG,Li-ping WANG,Xian TANG,Xin YANG,Kai TONG
A novel SiC–ZrB 2 coating was prepared using a two-step technique by slurry-sintering and chemical vapor reaction on carbon/carbon (C/C) composites. The SiC–ZrB 2 coating was composed of the scattered ZrB 2 phase and the continuous SiC phase. It was observed that a good adhesion was built between the coating and the C/C composites. The SiC–ZrB 2 coating samples exhibited a better ablation resistance in comparison with the uncoated C/C composites. The SiO 2 –ZrO 2 barrier layer, the heat dissipation of the gaseous products and the pinning effect of ZrO 2 all contributed to the good ablation resistance of the SiC–ZrB 2 coated composites.
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
CORROSION SCIENCE
·
2024
·
IF 7.4
Dongyang Zhang,Jie He,Yang Liu,Dazhao Liu,Cheng Yang,Lu Ren
The high-performance 3D C f-PyC /ZrB 2 -SiC composite was fabricated by vibration-assisted slurry impregnation and low-temperature hot pressing. The composite exhibited superior laser ablation resistance, leading to a low linear loss rate of 1.56×10 −2 mm/s at laser power density of 4878 W/cm 2 (Power 300 W, Laser beam diameter 2.8 mm) for 90 s. The coupling effect of a dense SiO 2 layer in fringe region followed by dense ZrO 2 layer in transitional region and next porous ZrO 2 layer in center region achieved superior laser ablation resistance.
研究领域:
材料科学
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激光工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2024
·
IF 4.2
Yang Chen,Zhi Wu,Xiaoming Lou,Jun Ding,Chengji Deng,Chao Yu,Hongxi Zhu,Tao Zhang
In view of the current situation that morphology of SiC whiskers synthesized from rice husk is too single, in this work, the chain-bead SiC whiskers were successfully synthesized via a simple molten-salt method. The effects of heating temperature on the phase composition and morphology of the product were compared under the salt-free and molten-salt conditions. The results indicated that the liquid environment formed by molten salt could retain SiO 2 in the product and promote the formation of cristobalite, inhibiting the formation of SiC. Compared with the SiC synthesized under salt-free condition (linear morphology), the SiC whiskers synthesized by the molten-salt method at 1400 °C showed a chain-bead morphology, which was composed of β-SiC stalks and round beads of amorphous SiO 2 on the stalks. Finally, the formation mechanism of chain-bead SiC whiskers in the molten-salt environment was clarified.
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
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Tong Che,Xiang-Yu Meng,Tao Yu,Rui-Fen Guo,Ping Shen
This study presents a novel approach for fabricating SiC-reinforced magnesium matrix composites by combining digital light processing (DLP) with pressureless infiltration. Pre-oxidation of SiC powder enhanced its wettability with the magnesium alloy, enabling the near-net-shape fabrication of honeycomb Mg-based composites with precisely controlled SiC and Al 2 O 3 powder ratios. The influence of varying ceramic content on the microstructure and compressive properties of the composites was investigated, revealing significant mechanical anisotropy. A combined approach utilizing fracture morphology analysis and finite element simulations elucidated the compressive behavior and failure mechanisms of the composites under different loading directions. This work not only offers a promising route for on-demand design and fabrication of Mg-based composites but also provides valuable insights into understanding the mechanical behavior of architected composites.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2023
·Vol. 20
·期 6
·3635-3646
·
IF 2.1
Haopeng Cai,Yinglong Wei,Baoguo Wang,Kun Jiang
It is necessary to give self-healing function to ceramic materials because of their notch sensitivity. In the past, studies on self-healing ceramics have mainly focused on the high-temperature stage, and less research has been done below 1000°C. In this study, SiC/Al 2 O 3 /TiB 2 ceramic composites were prepared by spark plasma discharge sintering, and cracks were introduced on the surface of the polished specimens. Crack healing at 600°C–800°C was investigated, and the recovery of macroscopic bending strength and the change of microscopic crack morphology after heat treatment were used to evaluate the crack-healing effect. It was found that the surface cracks of the material were completely filled and healed by oxidation products after heat treatment at 700°C for 60 min, and the highest healing efficiency exceeded 95% for both specimens with different crack lengths, and the main mechanism of crack by Si-Al-B-Na-Ca-O type glass produced by the reaction of TiB2 and a small amount of SiC with oxygen to produce oxides and glass powder. Good healing effect and fast healing speed effectively improve the service life and reliability of ceramic materials, which has very far-reaching significance for the practical application with ceramic materials.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）