MATERIALS LETTERS
·
2020
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IF 3.204
Yun Zhang,Shihua Ding,Tianxiu Song,Yingchun Zhang
CoSnNb 2 O 8 ceramic with medium-permittivity was initially generated. Compositionally induced phase formation was identified by X-ray diffraction. Tetragonal rutile-type CoSnNb 2 O 8 was obtained from the reaction of SnO 2 with intermediate phase CoNb 2 O 6 . Both the dielectric constant ε r and quality factor Q × f initially increased with the sintering temperature, reaching the maxima at around 1225 °C, and declined thereafter. They were discussed based on the ionic polarizabilities and packing fraction, respectively. The temperature coefficient of resonant frequency τ f primarily depended on the Nb-site bond valence, as well as oxygen octahedra distortion. When sintered at 1225 °C, the CoSnNb 2 O 8 ceramic exhibited optimum properties with ε r = 31.8, Q × f = 43,000 GHz, and τ f = 35.01 ppm/°C.
研究领域:
材料科学
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无机非金属材料
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介电物理
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功能陶瓷
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微波材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·Vol. 45
·期 3
·3710-3714
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IF 3.057
Yue Hu,Zhen Xiao,Huanping Wang,Can Ye,Yuqian Wu,Shiqing Xu
Porous CaSiO 3 ceramics were prepared via a solid-state reaction method using CaCO 3 and SiO 2 as raw materials and active carbon as a pore-forming agent. The results indicated that porous CaSiO 3 ceramics could be obtained under a low sintering temperature of 1320 °C. The addition of active carbon significantly affected the volume density, microstructure, pore size distribution and mechanical strength of porous CaSiO 3 ceramics. With the increase of active carbon content, the volume density decreased, meanwhile the pore size and porosity increased gradually. Besides, the three-point bending tests demonstrated that the mechanical strength was decreased with increasing active carbon content. However, all the porous ceramics still exhibited high mechanical strength. These results implied that the increase of active carbon content not only enlarged the pore size and enhanced the porosity, but also kept a remarkable mechanical strength of porous CaSiO 3 ceramics. Therefore, these rationally designed CaSiO 3 porous ceramics will be a highly potential material in various applications due to its high mechanical strength, low sintering temperature and narrow pore size distribution.
研究领域:
材料科学
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生物陶瓷
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组织工程
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生物医学材料
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无机非金属材料
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
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2023
·
IF 6.4
Songtong Xuan,Yuming Tian,Xiangchen Kong,Jianying Hao,Xiaojun Wang
The tuning of the properties of MgAl 2 O 4 -based materials has aroused great attention in the field of engineering technology. Along these lines, magnesia and alumina were used as raw materials to prepare spinel by the solid-phase sintering method at 1500–1600 °C. Particularly, the impacts of the different MgO/Al 2 O 3 molar ratios on the microstructural densification, sintering process and mechanical property of the fabricated materials were systematically studied. The results showed that the stoichiometric spinel with the highest concentration of ion diffusion possessed the best densification. And the magnesium-rich spinel displayed the better densification following with the formation of solid-solution, while the aluminum-rich spinel exhibited the worst ability in forming the solid-solution. Moreover, the different molar ratios changed the microstructure of the spinel, which induced the optimal sintering temperature of stoichiometric spinel to be at least 50 °C below that of the others. Specifically, in stoichiometric spinel, spinel grains grew up and formed obvious structure, which made the sintering process arrive at the end point and made the performance reach the best. Specifically, the flexural strength was 112.62 MPa and apparent porosity was 0.44%. However, no grown or developed spinel grains were observed for magnesium-rich/aluminum-rich spinels, which delayed the sintering process.
研究领域:
材料科学
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无机非金属材料
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陶瓷工艺学
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固态化学
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结构陶瓷
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2024
·Vol. 59
·期 36
·16909-16917
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IF 3.5
Xie Jingru,Fu Zhifen,Cheng Qing,Chen Chen,She Yubin,Li Xiangyi
Low temperature co-fired ceramics (LTCC) technology is extensively utilized to meet the requirements of device integration and miniaturization. Low-fired Li 3 Mg 2 NbO 6 ceramics doped with x wt% Li 2 O–MgO–B 2 O 3 –CaF 2 –SiO 2 glass (LMBCS, x = 0.5, 1.0, 1.5, 2.0) were prepared by the solid-state reaction method for applications in microwave communication materials. All samples exhibited a single-phase Li 3 Mg 2 NbO 6 structure. The addition of LMBCS glass effectively reduced the sintering temperature of Li 3 Mg 2 NbO 6 ceramics from 1250 °C to 875 °C. And adding LMBCS glass improved the Q × f value of Li 3 Mg 2 NbO 6 ceramics. The Li 3 Mg 2 NbO 6 -1.0wt% LMBCS ceramics exhibited outstanding microwave dielectric properties: ε r = 16.8, Q × f = 89,495 GHz, τ f = − 27.4 ppm/°C at 875 °C, which indicates that this ceramic is potential candidate materials for LTCC.
研究领域:
材料科学
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电子陶瓷
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功能材料
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无机非金属材料
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微波通信材料
✓ 已验证
DOI
高影响因子