CERAMICS INTERNATIONAL
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2024
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IF 5.1
Zaizhi Yang,Xi Wang,Liang Zhang,Hailin Li,Hui Zhang,Dong Xu
(Ca, Ta) co-doped TiO 2 ceramics were successfully prepared using flash sintering technology, and the effects of oxygen vacancies on the rapid densification and giant dielectric properties were studied. The results suggest that the maximum volume fraction of oxygen vacancies in flash-sintered samples is approximately 10%. Oxygen vacancies decrease the barrier energy level of atomic diffusion and provide convenient diffusion channels, resulting in rapid densification of the sample within 24 min at 1100 °C. All flash-sintered samples exhibit high relative density, exceeding 95%. Oxygen vacancies promote the electron-pinning defect dipole effect at low temperatures. As the temperature increases, carriers such as oxygen vacancies move to the grain boundary, forming an internal barrier layer capacitance effect. The optical dielectric constant reaches 7.25 × 10 4 , and the dielectric loss drops to 0.09. Oxygen vacancy play an important role in both flash sintering technology and the giant dielectric properties of co-doped TiO 2 ceramics.
研究领域:
材料科学
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物理学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Xiao Huang,Jiawen Tang,Yongjian Zhou,Kun Rui,Xin Ao,Yan Yang,Bingbing Tian
Li7La3Zr2O12 (LLZO) is one of the most promising candidate solid electrolytes for high-safety solid-state batteries. However, similar to other solid electrolytes containing volatile components during high-temperature sintering, the preparation of densified LLZO with high conductivity is challenging involving the complicated gas–liquid–solid sintering mechanism. Further attention on establishing low-cost laborastory-scale preparation craft platform of LLZO ceramic is also required. This work demonstrates a “pellet on gravel” sintering strategy, which is performed in a MgO crucible and box furnace under ambient air without any special equipment or expensive consumables. In addition, the competition between lithium loss from the sintering system and internal grain densification is critically studied, whereas the influences of particle surface energy, Li-loss amount, and initial excess Li2O amount are uncovered. Based on the sintering behavior and mechanism, optimized craft platform for preparing dense LLZO solid electrolytes including mixing, calcination, particle tailoring and sintering is provided. Finally, exemplary Ta-doped LLZO pellets with 2 wt % La2Zr2O7 additives sintered at 1260–1320 °C for 20 min deliver Li+ conductivities of ∼9 × 10–4 S cm–1 at 25 °C, relative densities of >96%, and a dense cross-sectional microstructure. As a practical demonstration, LLZO solid electrolyte with optimized performance is applied in both Li–Li symmetric cells and Li–S batteries. This work sheds light on the practical production of high-quality LLZO ceramics and provides inspiration for sintering ceramics containing volatile compounds.
研究领域:
材料科学
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固体离子学
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陶瓷工艺
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储能技术
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电池技术
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DOI
高影响因子
Journal of Central South University
·
2026
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IF 4.7
Jiang Hao-li,Yang Ya-ting,Lu Yu-gen,Yang Jia-mian,Sun Guo-quan,Cui Hong-zhi,Min Fan-lu,Wang Cong-xu,Xu Chuan-hua,Li Gai-ye,Zhang Jian-feng
Coarse-grained WC-10Co cemented carbides are indispensable for demanding applications such as rock drilling and shield tunneling, yet their development is restricted by poor mixing uniformity and the inherent hardness-toughness trade-off. To address this issue, a series of coarse-grained WC-10Co cemented carbides was developed by systematically tuning the ratios of La 2 O 3 and Y 2 O 3 additives via a co-precipitation and hydrogen reduction. The microstructures and mechanical properties were highly sensitive to this ratio. The optimal balance was achieved at a La: Y atomic ratio of 1:2, yielding a hardness of 86.6 HRA, a bending strength of 2201 MPa, and a remarkable fracture toughness of 25.72 MPa·m 1/2 . This improvement is mainly attributed to a synergistic interface-pinning mechanism. Specifically, trapezoidal La 2 O 3 and spherical Y 2 O 3 particles preferentially segregate at the WC/Co phase boundaries, thereby inhibiting abnormal WC grain growth and suppressing the martensitic transformation of ductile face-centered cubic cobalt (Co FCC ). Consequently, optimizing the additive ratio effectively alleviated the hardness-toughness trade-off, providing an effective paradigm for tailoring high-performance cemented carbides through precise powder-mixing engineering.
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2025
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IF 8.3
Fei-Fei Lu,Jia-Hong Li,Si-Yuan Kang,Cheng-Xin Li,Yuan Gao,Chang-Jiu Li
A major challenge in the development of Metal-supported solid oxide fuel cells (MS-SOFCs) is achieving a fully densified electrolyte while staying within the temperature limits that the metal substrate can withstand. This study investigates the impact of Co doping on the sintering behavior of Gd 0.1 Ce 0.9 O 2-δ (GDC) and its application in MS-SOFCs. The study identifies the formation of a low-melting-point Co–Ce-Gd-O phase as a key factor that facilitates viscous flow. HRTEM results reveal slight Co aggregation at the grain boundaries, indicating that Co doping enhances intergranular element diffusion and particle sliding. This effect contributes to a significant reduction in the onset sintering temperature by over 300 °C. The 1CoGDC electrolyte exhibits high ionic conductivity of 1.01 × 10 −2 S cm −1 at 550 °C, highlighting its advantages at intermedium-low temperature. Notably, the MS-SOFCs is fabricated through screen printing with 25 μm in thickness of 1CoGDC electrolyte at sintering temperature of 1050 °C. The MS-SOFCs exhibits an open circuit voltage of 0.90V at 650 °C and showed high power density of 502.44 mW cm −2 under hydrogen as the anode fuel and flowing air at the cathode, the remarkable voltage clearly demonstrates the gas-tightness of the GDC electrolyte. Furthermore, the cell performance remained stable after 120 h long-term operation, demonstrating 1CoGDC electrolyte appear outstanding performance and potential application in MS-SOFCs.
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DOI
高影响因子
Journal of the Mechanical Behavior of Biomedical Materials
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2023
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IF 3.9
Mengxing Ge,Deqiao Xie,Youwen Yang,Zongjun Tian
Over the past few years, biodegradable ceramic scaffolds have gained significant attention in the field of bone repair. Calcium phosphate (Ca 3 (PO 4 ) 2 )- and magnesium oxide (MgO)-based ceramics are biocompatible, osteogenic, and biodegradable, making them attractive for potential applications. However, the mechanical properties of Ca 3 (PO 4 ) 2 are limited. We developed a magnesium oxide/calcium phosphate composite bio-ceramic scaffold characterized by a high melting point difference, using vat photopolymerization (VP) technology to address this issue. The primary goal was to fabricate high-strength ceramic scaffolds using biodegradable materials . In this study, we investigated ceramic scaffolds with varying MgO contents and sintering temperatures . We also discussed the co-sintering densification mechanism of high and low melting-point materials associated with composite ceramic scaffolds. During sintering, a liquid phase was generated, which filled up the pores generated during the vaporization of additives (such as resin) under the influence of capillary force . This led to an increase in the extent of ceramic densification realized. Moreover, we found ceramic scaffolds with 80 wt% MgO exhibited the best mechanical performance. This kind of composite scaffold performed better than pure MgO scaffold. The results reported herein highlight that high-density composite ceramic scaffolds can be potentially used in the field of bone repair.
研究领域:
生物材料学
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骨修复领域
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
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2025
·Vol. 51
·期 10
·12663-12672
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IF 5.6
Jiali Li,Hanlu Xing,Shijie Xue,Tao Ma,Jun Sun,Kun Hu,Lin Chen,Xiaoxiao Li,Yi Gong,Xian Zhang,Xingyou Tian
The application field of low temperature co-fired ceramics (LTCC) has been further expanded with the development of electronic packaging technology. Nevertheless, during the preparation process, solvents often volatilize leading to toxicity to humans and environmental pollution. Furthermore, in certain applications, LTCC materials must possess higher strength and thermal conductivity . Herein, we developed a kind of Bi 2 O 3 -B 2 O 3 -SiO 2 -CuO-Al 2 O 3 (BBSCA)/Al 2 O 3 /Al 2 O 3 fibers LTCC composites, synthesized by aqua-based molding and hot-press solid-state reaction method. The addition of Al 2 O 3 fibers can construct the two-dimensional structure and enhance thermal conductivity of the composites. When the Al 2 O 3 fibers content reaches 2 wt%, the resulting composite exhibits a significant bending strength of 308 MPa and an elevated thermal conductivity of 9.31 W/(m·K). Additionally, the composites exhibit excellent dielectric properties , with a dielectric constant of 10.17 and tanδ = 1.24 × 10 −3 at 13 GHz. This work provides a novel approach to construct high-strength and high thermal conductivity LTCC based on environmentally friendly preparation processes.
研究领域:
材料科学
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陶瓷与复合材料
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电子封装
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热管理
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介电材料
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2024
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IF 3.5
Hongbin An,Ruoyu Chen,Saisai Li,Lingfeng Huang,Wenbao Jia,Qianfang Wu,Aiqing Mao
Powder synthesis is crucial for achieving the densification and facilitating widespread applications of high entropy carbide (HEC). Specifically, the production of fine particle-size powders is essential to enhance the densification of HECs. Consequently, this paper proposes the molten salt method for synthesizing HEC powders. The synthesis process successfully yielded (Ta Nb Ti V) C powders with a particle size of only 0.44 µm at 1400°C, exhibiting a uniform distribution of each element. Subsequent densification of (Ta Nb Ti V) C within the 1700–1900°C temperature range was carried out using spark plasma sintering. It was observed that as the densification temperature increased, the densification and mechanical properties of HEC significantly improved. This study presents innovative ideas for the preparation of HEC at lower temperatures.
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 Thermal Science
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2025
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IF 2.6
Li Chuan,Han Li,Li Qi,Du Yanping,Wu Yuting
Cold sintering as a new technology for the fabrication of ceramic composites could overcome the shortcomings of traditional high temperature sintering approach and achieve dense structure in the composite at a relatively low temperature (<200°C). In this work, a shape stabilization phase change composite is fabricated and investigated by dint of such new fabrication approach, in which a mixed nitrate salt of NaNO 3 -KNO 3 is used as phase change material and magnesia powder is acted as structure skeleton. Using of deionized water as sintering additive, the effects of sintering agent content, sintering temperature, uniaxial pressure and time on the composite microstructure characteristics and macroscopic properties are evaluated. The results show that the liquid salt could be effectively accommodated in the magnesia skeleton, forming a dense and stable structure in the composite. There is existence of optimal cold sintering parameters at which a benign combination of mechanical strength and thermal cycling performance could be attained in the composite. Under the sintering temperature of 150°C, duration time of 8 min, uniaxial pressure of 150 MPa, and water mass content of 7%, the fabricated composite exhibits a heat storage density of 610 kJ/kg at its potential utilization temperature range of 30°C–580°C and a compressive strength over 240 MPa with a dense density higher than 98%, demonstrating that it can be a viable alternative used in thermal energy storage domains.
研究领域:
材料科学
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能源工程
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2024
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IF 3.5
Xiaohui Wu,Xixi Wang,Yulan Jing,Yuanxun Li,Hua Su
With the emergence of 5G–6G communication technology, the miniaturization and integration of electronic components are crucial. Ba 3 Ti 4 Nb 4 O 21 (BTN) ceramics with hexagonal structures have attracted special attention due to their high dielectric constant, which shows greater application potential in communication base stations and dielectric resonators. However, its high sintering temperature and low-quality factors also greatly limit the application field. In this paper, boric acid (H 3 BO 3 ) as a dopant, was used to investigate the influence on the structure, microstructure, Raman spectrum, and microwave properties for Ba 2.92 Cu 0.08 (Zn 1/3 Nb 2/3 ) 2 Ti 2 Nb 4 O 21 (BCZTN)- x HB (0.25≤ x ≤1.25 wt%) ceramics. The results reflected that H 3 BO 3 was an effective additive, which could promote ceramic densification, accelerate grain growth and uniform distribution, and enhance its microwave performance. Among them, high densification was 93.92 ± 0.35%, and the Q × f value ∼16981 ± 340 GHz at x = 0.75, was more than 2∼3 times higher than other BTN-based ceramics. Superior microwave dielectric properties were achieved for 0.75 wt% H 3 BO 3 -doped BCZTN ceramic sintered at 900°C: ε r ∼42.35 ± 0.48, Q× f ∼16981 ± 340 GHz, and τ f ∼40.02 ± 1.43 ppm/°C. More encouragingly, BCZTN-0.75HB ceramic did not chemically react with Ag, which suggested that it had the potential to be a candidate material for low-temperature co-fired ceramics base station communication devices.
研究领域:
材料科学
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电子工程
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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）