Advances in Applied Ceramics
·
2016
·
IF 1.162
X. J. Zeng,W. L. Liu
B4C green tapes are prepared by aqueous tape casting and a spark plasma sintering (SPS) process using polyethylenimine (PEI) as dispersant, hydroxypropyl methyl cellulose (HPMC) as binder and polyethylene glycol (PEG) as plasticiser. The influences of solid content, dispersant content, mass ratio of plasticiser to binder (R value) and milling time on the slurry viscosity are studied. The samples are characterised by means of hardness tester, universal testing machine and scanning electron microscopy. The results indicate that the solid content of B4C slurry achieves 47.5 wt-% with milling time of 12 h when the content of PEI, HPMC and PEG is 1.5, 5 and 5 wt-%, respectively. The relative density of B4C ceramics subject to SPS at 1600°C and 50 MPa for 8 min is up to 97.2%. The Vickers hardness, flexural strength and fracture toughness of B4C ceramics reach 36.5 ± 0.7 GPa, 510.3 ± 19.4 MPa and 5.04 ± 0.29 MPa m−1/2, respectively.
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2024
·
IF 6.1
Qianglong He,Wenchao Guo,Yunwei Shi,Aiyang Wang,Weimin Wang,Zhengyi Fu
In this study, B 4 C–TiB 2 –graphite ceramic composites were prepared via reactive hot-pressing sintering using B 4 C and TiC as the raw materials. The reaction process, microstructure, and mechanical properties were investigated. The solid-phase reaction is a diffusion-controlled process, wherein the B atoms diffuse into TiC and react to form TiB. Thereafter, TiB 2 is generated with the entry of subsequent B atoms. A core–shell structure is formed, wherein TiB 2 particles are wrapped by layered graphite. The products TiB 2 and graphite inhibit the growth of B 4 C matrix grains, which are instrumental in fine grain strengthening. In addition, the novel TiB 2 –graphite-agglomerated structure significantly improves the fracture toughness of the ceramic composites through crack deflection, bridging, and branching toughening mechanisms. Therefore, the comprehensive properties of B 4 C–TiB 2 –graphite ceramic composites are better than those of pure B 4 C ceramics. Specifically, the fracture toughness is approximately 6.77 MPa m 1/2 , which is considerably higher than that of pure B 4 C ceramics (2.47 MPa m 1/2 ).
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
MATERIALS LETTERS
·
2016
·
IF 2.437
Qing Xiang,Daixiong Zhang,Jirao Qin
Boron carbide (B 4 C) coating having potential in application of cermet , armor materials, and wear-resistant components have attracted considerable attention due to its excellent properties, such as high melting point, high hardness, high neutron absorption, low density, and good chemical stability. In this study, the nano-B 4 C coatings have been successfully fabricated by the electrophoretic deposition (EPD) method in a solvent of isopropyl alcohol containing Polyethyleneimine (PEI). The electrophoretic B 4 C coating was sintered at 1000 °C for 6 h under a constant flow of argon. The electrophoretic coating was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, and the result indicates that B 4 C coating is of good film characteristics after sintering. Furthermore, the influence of addition amount of PEI on the EPD kinetics of the nano-B 4 C was investigated in detail. The results show that the optimal addition of PEI would vary with the suspension concentration of nano-B 4 C. Generally speaking, the needed addition amount of PEI for sufficiently modifying the surface charging of nano-B 4 C would increase with the amount of nanoparticles in suspension. This work demonstrates that EPD method is a facile and effective approach in the preparation of B 4 C coatings for potential applications.
研究领域:
材料科学
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表面工程
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DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2023
·Vol. 21
·期 1
·438-450
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IF 2.1
Bo Wang,Delong Cai,Shiqi Li,Haoyi Wang,Wenhua Zou,Zhihua Yang,Xiaoming Duan,Peigang He,Daxin Li,Wenjiu Duan,Yanzhi Pan,Yueqian Zhao,Dechang Jia,Yu Zhou
B 4 C–MAS and B 4 C–TiB 2 –MAS ceramic composites were prepared by hot pressed sintering. The effects of particle size of B 4 C and TiB 2 content on the microstructure and general mechanical properties of the ceramic composites were investigated by using X-ray diffractometer, scanning electron microscope, and universal testing machine. The strengthening and toughening mechanism of ceramic composites is mainly attributed to the addition of magnesium–aluminosilicate (MAS) and thermal mismatch effect of TiB 2 . When the TiB 2 content was 20 wt.%, the bending strength, fracture toughness, and Vickers hardness of B 4 C–TiB 2 –MAS ceramic composites were 375 MPa, 4.42 MPa·m 1/2 , and 23.9 GPa, respectively, and its relative density could reach 99.7%. The dynamic mechanical properties of B 4 C–TiB 2 –MAS ceramic composites were investigated at strain rates of 2000–6000 s −1 using a Separate Hopkinson Pressure Bar (SHPB) device. The results showed that the B 4 C–TiB 2 –MAS ceramic composites exhibited significant strain rate sensitivity. The dynamic compressive strength of the ceramic composites increased from 4634 to 5734 MPa with increasing strain rate in the tested strain rate range.
研究领域:
材料科学
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力学
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DOI
高影响因子
Chinese Physics B
·
2017
·Vol. 26
·期 1
·018102
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IF 1.223
Hong-Sheng Jia,Pin-Wen Zhu,Hao Ye,Bin Zuo,Yuan-Long E,Shi-Chong Xu,Ji Li,Hai-Bo Li,Xiao-Peng Jia,Hong-An Ma
Improving the thermal stability of diamond and other superhard materials has great significance in various applications. Here, we report the synthesis and characterization of bulk diamond–cBN–B4C–Si composites sintered at high pressure and high temperature (HPHT, 5.2 GPa, 1620–1680 K for 3–5 min). The results show that the diamond, cBN, B4C, Bx
SiC, SiO2 and amorphous carbon or a little surplus Si are present in the sintered samples. The onset oxidation temperature of 1673 K in the as-synthesized sample is much higher than that of diamond, cBN, and B4C. The high thermal stability is ascribed to the covalent bonds of B–C, C–N, and the solid-solution of Bx
SiC formed during the sintering process. The results obtained in this work may be useful in preparing superhard materials with high thermal stability.
研究领域:
材料科学
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高温高压合成
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DOI
高影响因子
Materials
·
2025
·Vol. 18
·期 4
·744
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IF 3.2
Ya-Long Wang,Guo-Hua Zhang
Submicron-sized TiB2powders (300 nm–1 μm) were prepared by the reaction of TiC, B4C, and Ca assisted by molten CaCl2. The optimal reaction procedure (1200 °C and 25 wt.% CaCl2+ 25 wt.% Ca) was obtained by exploring the effects of the boronization reaction temperature and the addition of an amount of CaCl2. It was found that the introduction of CaCl2not only promoted the reaction but also effectively inhibited the volatilization of excess Ca. Furthermore, SEM images of the products showed that the morphology and particle size of TiB2were inherited from the carbothermal reduction product TiC, which was dominated by the “template/growth” mechanism. The process of the boronization reaction was that B atoms migrated from B4C and replaced the C atoms in the lattice of TiC.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2016
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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
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·
IF 2.758
Wei-Ming Guo,Zhi-Lin Zhang,Jing-Xi Li,Yang You,Shang-hua Wu,Hua-Tay Lin
Al 2 O 3 –B 4 C ceramics had poor densification, due to the formation of Al 18 B 4 O 33 phase by reaction between Al 2 O 3 and B 2 O 3 on the surface of B 4 C. In the present work, Y 2 O 3 or Ti additive together with ZrO 2 from milling media were introduced into Al 2 O 3 –B 4 C ceramics. Results showed that Y 2 O 3 reacted with B 2 O 3 to produce YBO 3 phase, and removed Al 18 B 4 O 33 phase, resulting in the improved densification and the coarse microstructure. However, Ti and ZrO 2 reacted with B 2 O 3 to produce hard TiB 2 and ZrB 2 phases, removed the most of Al 18 B 4 O 33 phase, refined microstructure by pinning effect of hard particles, and improved densification and mechanical properties .
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 NANOPARTICLE RESEARCH
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2022
·Vol. 24
·期 12
·1-13
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IF 2.533
Wang Yu,Li Yao,Yang Xiao-Hui,Zhang Guo-Hua
Nano-Zirconium diboride (ZrB 2 ) powder was vital raw material for manufacturing ultra-high temperature ceramics (UHTCs) and C/C composite materials, which were widely used in extreme environment. In this paper, a convenient way of synthesizing nano-ZrB 2 powder was proposed. Firstly, the precursor consisting of ultrafine-ZrC and C was obtained via vacuum carbothermal reduction of nano-ZrO 2 . And then, the carbothermal reduction product was boronized by B 4 C in Ca melt. In boronation process, Ca melt would play a key role as decarburizer. By boronation reaction at 1373 K and 1473 K, cauliflower-shaped ZrB 2 particle and smooth polyhedral ZrB 2 particle were obtained, respectively. XRD and BET analyses showed that the grain sizes and BET-equivalent particle diameters of these two products were less than 100 nm.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
MATERIALS SCIENCE FORUM
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2016
·
IF 0
Wei Liang Liu,Min Wu,Zhong Tao Shi,Zhao Liang Xu,Jie Ping Ruan
B4C ceramic tapes were prepared by aqueous tape-casting with boron carbide powders as starting material, deionized water as solvent, polymine (PEI) as dispersant, polyethylene glycol (PEG) as plasticizer, poval (PVA) or gelatin as binders. The influences of pH, dispersant content, kind and content of binder on the stability and rheological property of tape slurries were studied. The experimental results indicated that, when the pH was ranged in 3-4, the slurries with good stability and good rheology could be obtained with 0.8 wt% PEI, 4.0 wt% PVA or 6.5 wt% gelatin. PVA as binder made cast tape with certain strength, and gelatin as binder made cast tape with poor strength.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
DOI
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Hu Zhou,Miao Li,Liqin Chen,Huipeng Cheng,Dan Li,Changxin Tang,Jiren Yuan,Feigao Xu
In this work, Fe 3 O 4 /B 4 C (FeB) composites were successfully prepared by a facile co-precipitation process. FeB composites were characterized using XRD , FTIR, N 2 adsorption-desorption, XPS, etc techniques and then used as heterogeneous Fenton catalysts to activate green oxidant (H 2 O 2 ) for the degradation of TCH. The removal efficiency of TCH by FeB composites was explored including different parameters of Fe 3 O 4 loading on B 4 C, catalyst dosage, initial solution pH, H 2 O 2 dosage, and reaction temperature. The highest photo-Fenton catalytic efficiency was obtained for the composites with a mass ratio of Fe 3 O 4 to B 4 C of 1:0.75. At this time, the removal efficiency of Fe 3 O 4 /B 4 C was 2 times and 391 times that of the parent Fe 3 O 4 and B 4 C, respectively, and B 4 C can effectively improve the efficiency of the Fenton cycle. h + , e - , and ·OH were mainly responsible for the degradation of TCH by Fe 1 B 0.75 composites. After repeated use for five times, the removal efficiency of the catalyst was reduced by only 8.0%. The disparity in work functions by density functional theory calculations confirmed the formation of an internal electric field at the Fe 3 O 4 /B 4 C composites interface, which contributed the transfer of charge carriers between the Fe 3 O 4 and B 4 C. Moreover, the FeB composite showed a high stability, indicating that FeB composites may be a promising heterogeneous catalyst .
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
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IF 5.532
Lin-Lin Zhu,Min-Min Dai,Xin Xu,Guang-Xiang Zhang,Yu-Jian Jian,Cheng-Cai Zhao,Hua-Tay Lin
In this study, B 4 C–SiO 2 was employed as the joining material via a screen-printing method to join alumina (Al 2 O 3 ) ceramics at 1000 °C in ambient air. Effects of mass ratios of B 4 C and SiO 2 ranging from 1:0.5 to 1:2.5 on the composition, microstructure, and mechanical properties of the joints were investigated. When the content of SiO 2 was equal or greater than that of B 4 C, the interlayer of the brazed joints was defect-free and consisted of Al 4 B 2 O 9 whiskers and calcium borosilicate glass based on microscopically electronic analyses. With the content of SiO 2 increased, the shear strength of the joints increased first and then decreased. The average shear strength of the joint reached the maximum value of 110 ± 19 MPa when the mass ratio of B 4 C to SiO 2 was 1:2. The current study demonstrated that the screen-printed B 4 C–SiO 2 system could be a very beneficial approach to obtain high strength Al 2 O 3 joints with defect-free interlayer at relatively low joining temperatures in air.
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
危险品化学品经营许可证（带存储）