Article
Chemistry, Physical
Xian Zhang, Yongping Pu, Lei Zhang, Xiang Lu, Yating Ning, Jinbo Zhang, Yangchao Shang
Summary: This paper systematically investigates the effects of annealing atmosphere on the dielectric properties of Sr1-xErxTiO3 ceramics (x = 0-0.014). The x = 0.012 ceramic samples annealed in air exhibit stable insulation resistivity of over 109 & omega; & BULL; cm (DC 0-150 V), CP (16,635 @ 1 kHz, 16,822 @ 1 MHz), and ultralow dielectric loss (0.006 @ 1 kHz, 0.02 @ 1 MHz). Through comprehensive analysis of dielectric responses, X-ray photoelectron spectroscopy (XPS), UV-visible absorption spectrum, and complex impedance data, it is found that defect dipoles [TiTi VO TiTi], [ErTi VO], and [Er ErTi] form in Sr1-xErxTiO3 (x = 0.012) ceramic annealed under flowing air. By simulating the industrial environment using variable temperature in situ resistance monitoring equipment, this study provides insights into the insulating properties and microscopic mechanism of oxygen vacancy diffusion in ceramics under different voltages and temperatures, which is significant for achieving desired colossal permittivity, ultra-low dielectric loss, and insulation resistivity performance in real applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Nanoscience & Nanotechnology
Xian Zhang, Yongping Pu, Lei Zhang, Jinbo Zhang, Yating Ning, Yangchao Shang, Xiang Lu, Xuqing Zhang
Summary: In this study, high-performance Sr1-xErxTiO3 ceramics were successfully prepared by adjusting the sintering atmosphere. The ceramic sintered in hydrogen exhibited colossal permittivity, ultralow dielectric loss, and excellent frequency and temperature stability. The outstanding properties of these ceramics were attributed to the defect dipoles and defect clusters, as revealed by various analysis techniques.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Ceramics
Bo Wang, Yongping Pu, Lei Zhang, Yangchao Shang, Jiamin Ji, Tianchen Wei, Tao Ouyang, Shiyu Zhou, Dawei Wang
Summary: In this study, active defect dipoles were induced in polycrystal ceramics to achieve high colossal permittivity, low dielectric loss, and high insulation resistivity. The results showed stable dielectric performance under external stimulus, with high permittivity, low dielectric loss, and high insulation resistivity.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Jiangtao Fan, Gang He, Zhenzhu Cao, Yongfan Cao, Zhen Long, Zhanggui Hu
Summary: Through the synthesis of a system of acceptor Gd3+ and donor Ta5+ co-doped (Gd0.5Ta0.5)xTi1-xO2 (GTTOx, x = 0, 0.01, 0.02, 0.04, 0.06) ceramics, dielectric response is enhanced. A colossal permittivity (CP, 2.65 x 104@1 kHz, 2.37 x 104@1 MHz), a very low dielectric loss (tano, 0.007@1 kHz, 0.03@1 MHz), good stability of frequency (20-106 Hz) and temperature (RT-250 degrees C, D epsilon 0 (T)/epsilon 030 < +/- 15%, at 1 kHz) were achieved simultaneously in GTTO0.01 ceramic. The main reasons for the improved dielectric properties are the synergistic effect of the electron pinning defect-dipole (EPDD) model, the internal blocking layer capacitance (IBLC) mechanism, and electrode response. This work provides a promising approach for the design of defect-related high-performance giant dielectric ceramics.
JOURNAL OF MATERIOMICS
(2023)
Article
Chemistry, Physical
Kai Zhang, Lingxia Li, Menglong Wang, Weijia Luo, Wenbo Wang
Summary: By adjusting donor ions doping and the distribution of oxygen vacancies, BaTiO3 ceramics with colossal permittivity and high insulation resistivity can be achieved, providing a technical basis for the preparation of single-layer microchip capacitors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Electrical & Electronic
M. Bourguiba, Z. Raddaoui, S. El Kossi, Thamraa Al-shahrani, A. Dhahri, M. Chafra, J. Dhahri, H. Belmabrouk
Summary: The study investigated the dielectric and optical processes of LBCMT manganite, demonstrating normal behavior in terms of dielectric constants and non-Debye type relaxation phenomena. The Nyquist plots were adjusted by an appropriate equivalent circuit, indicating inductance related to grains and grain boundaries. The activation energies for conduction and relaxation mechanisms were found to be <1 eV, suggesting mainly ionic conductivity of oxygen rather than electronic conductivity and oxygen vacancies. The optical properties were studied using spectroscopic ellipsometry, revealing the refractive index and extinction coefficient at room temperature.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Noppakorn Thanamoon, Prasit Thongbai
Summary: By adjusting the sintering conditions, including temperature and duration, TNTO ceramics with ultra-high dielectric permittivity and low loss tangent were successfully prepared. The analysis of phase structure and microstructure provided insights into the mechanism for the colossal permittivity behavior.
MATERIALS RESEARCH EXPRESS
(2023)
Article
Chemistry, Physical
Jiangtao Fan, Zhen Long, Haitao Zhou, Gang He, Zhanggui Hu
Summary: (Tm+Nb) co-doped TiO2 ceramics were prepared and their phase, microstructure, and dielectric properties were investigated. The ceramics with a co-doping concentration of 0.01 exhibited ultralow dielectric loss and colossal permittivity, showing excellent temperature and frequency stability in a certain range. The dielectric properties of the ceramics were influenced by several factors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Theeranuch Nachaithong, Narong Chanlek, Pairot Moontragoon, Pornjuk Srepusharawoot, Prasit Thongbai
Summary: Ti1-x(Co1/3Ta2/3)xO2 ceramics prepared by a mixed oxide method exhibit low dissipation factor and excellent temperature stability, with high dense sintered-ceramics having low tan delta of 0.015-0.043 and high dielectric permittivities of 7.0-9.1 x 104 at 1 kHz. The microstructure of the ceramics shows homogeneous distribution of the dopants. Impedance spectroscopy reveals the electrically heterogeneous microstructure and the contributions of intrinsic and extrinsic factors to dielectric relaxations. The high permittivity is attributed to intrinsic defect dipoles and extrinsic internal barrier layer capacitor (IBLC) effects, while the low tan delta is primarily caused by the IBLC effect associated with high resistance and defect dipoles.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Physical
Jakkree Boonlakhorn, Narong Chanlek, Jedsada Manyam, Pornjuk Srepusharawoot, Prasit Thongbai
Summary: The dielectric permittivity of CaCu3Ti4O12 was enhanced by doping with Mg at the Cu site, and further enhanced by codoping with Ge at the Ti site. The enhancement was attributed to the increased ratio of grain size to grain boundary thickness and increased free charge inside semiconducting grains. The double-step reduction in the low-frequency loss tangent was due to the enhanced resistance of the insulating grain boundaries from the segregation of the Cu-rich phase.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Biochemistry & Molecular Biology
Noppakorn Thanamoon, Narong Chanlek, Pornjuk Srepusharawoot, Ekaphan Swatsitang, Prasit Thongbai
Summary: A novel giant dielectric (GD) oxide with extremely large dielectric permittivity and low loss tangent was reported in this study, attributed to the synthesis of Lu3+/Nb5+ co-doped TiO2 (LuNTO) ceramic with appropriate co-dopant concentration. The remarkable dielectric properties of LuNTO ceramics were due to their inhomogeneous microstructure, composed of semiconducting grains, ultra-high-resistance grain boundaries, and secondary microwave phase particles. The enhancement of grain boundary properties was identified as key to improving the overall dielectric properties of GD oxides.
Article
Engineering, Electrical & Electronic
Vishnu Shankar Rai, Santosh Pandey, Vinod Kumar, Manish Kumar Verma, Atendra Kumar, Shruti Singh, Dinesh Prajapati, K. D. Mandal
Summary: This paper reports the synthesis and characterization of Mg-doped and undoped BCTO ceramics, with XRD, TEM, AFM, dielectric and impedance spectroscopic analysis confirming their properties. The high dielectric constant was attributed to the IBLC mechanism, and impedance and modulus studies indicated the presence of Maxwell-Wagner relaxation in the ceramics. The ceramics exhibited Arrhenius behavior in the temperature range of 300-500 K.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Jiangtao Fan, Zhen Long, Zhanggui Hu
Summary: High-performance giant dielectric ceramic materials are prepared in this study, and the sample with x = 0.01 shows the best dielectric performance. The dielectric constant varies with frequency, being related to the electron-pinned defect-dipole effect at high frequencies and the internal barrier layer capacitance effect and electrode effect at low and medium frequencies.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Liang Zhang, Shuaishuai Feng, Nan Wang, Jiamao Li, Hailing Li, Dong Xu
Summary: In this study, (Sr + Sb) co-doped TiO2 colossal dielectric ceramics were successfully fabricated using flash sintering technology under an electric field of 500 V cm(-1). The flash sintering parameters, phase structure, and electrical properties of the ceramics were analyzed. Compared to conventional sintering methods, the flash sintering process reduced the sintering temperature by approximately 200 degrees C and the sintering time by 90% (18 min, 1150 degrees C). The co-doped TiO2 ceramics showed excellent dielectric properties (epsilon' > 10(4)). The successful preparation of co-doped rutile TiO2 dielectric ceramics expands the application range of flash sintering technology and holds great research significance.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Wided Hizi, Hedi Rahmouni, Nima E. Gorji, Ahlem Guesmi, Naoufel Ben Hamadi, Lotfi Khezami, Essebti Dhahri, Kamel Khirouni, Malek Gassoumi
Summary: La0.9Sr0.1MnO3 nanoparticles were prepared using the citrate-gel route and sintered at different temperatures. The increase in sintering temperature led to an increase in grain size and a shift in the metal-semiconductor transition temperature of the material. The electrical properties were found to be influenced by the microstructure of the material and the relaxation phenomenon.
Article
Chemistry, Physical
Zhenpeng Xu, Lingxia Li, Shihui Yu, Mingkun Du, Weijia Luo
JOURNAL OF ALLOYS AND COMPOUNDS
(2019)
Article
Chemistry, Physical
Wenbo Wang, Lingxia Li, Te Lu, Ning Zhang, Weijia Luo
JOURNAL OF ALLOYS AND COMPOUNDS
(2019)
Article
Materials Science, Multidisciplinary
Kai Zhang, Lingxia Li, Menglong Wang, Wenbo Wang, Weijia Luo
Article
Chemistry, Physical
Weijia Luo, Lingxia Li, Bowen Zhang, Jianli Qiao
JOURNAL OF ALLOYS AND COMPOUNDS
(2020)
Article
Materials Science, Ceramics
Kai Zhang, Lingxia Li, Menglong Wang, Weijia Luo
CERAMICS INTERNATIONAL
(2020)
Article
Materials Science, Multidisciplinary
Wei Peng, Lingxia Li, Shihui Yu, Pan Yang, Kangli Xu, Weijia Luo
Summary: High-performance flexible transparent p-CuI films were successfully prepared on polycarbonate substrates, exhibiting polycrystalline with zinc blende structure and highly preferred oriented (1 1 1) plane. These films show excellent electrical performance with high average transmittance and conductivity, surpassing rigid p-type transparent conductors prepared at high temperatures. Additionally, the flexible p-CuI films demonstrate superior durability and flexibility, making them promising for flexible and wearable electronics.
Article
Chemistry, Physical
Kai Zhang, Lingxia Li, Menglong Wang, Weijia Luo, Wenbo Wang
Summary: By adjusting donor ions doping and the distribution of oxygen vacancies, BaTiO3 ceramics with colossal permittivity and high insulation resistivity can be achieved, providing a technical basis for the preparation of single-layer microchip capacitors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Ceramics
Shun Wang, Weijia Luo, Lingxia Li, Mingkun Du, Jianli Qiao
Summary: The multilayer architecture of ZnTi0.97Ge0.03Nb2O8-TiO2-ZnTi0.97Ge0.03Nb2O8 ceramics demonstrates advantages and control over microwave dielectric properties. Through the interaction of components in the tri-layer structure, a cooperative optimization of microwave dielectric properties is achieved.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Physics, Applied
Weijia Luo, Xubin Wang, Shun Wang, Xueqian Wang, Zetan Liu, Lingxia Li, Fan Hu, Yongzheng Wen, Ji Zhou
Summary: Currently, the miniaturization requirements of microwave or terahertz perfect absorbers using dielectric ceramic-based metamaterials cannot be met due to the low dielectric constant. In this study, we introduced conductivity loss through the carburizing process in order to improve the absorbers, and demonstrated the mechanism using electromagnetic simulation. By establishing a carburizing channel in Ba4Sm9.33Ti18O54 ceramics with an appropriate dielectric constant, the microwave absorbance was doubled and the period was reduced by half compared to pure ceramic-based absorbers. This approach can be extended to various metamaterials using dielectric resonance, offering an effective strategy for device miniaturization and potentially breaking the restrictive relationship between device size and dielectric constant.
APPLIED PHYSICS LETTERS
(2022)
Article
Materials Science, Ceramics
Zheng Sun, Xiaosong Lvu, Weijia Luo, Jingda Guo, Qiuyue Wang, Jingru Hua
Summary: This study investigated the effects of BCu additive on the microstructure and microwave dielectric properties of ZZNT ceramics. The results showed that a small amount of BCu could significantly reduce the sintering temperature and form rutile-like and Zn0.17Nb0.33Ti0.5O2 secondary phases. The BCu-added ceramics also demonstrated excellent chemical compatibility with Ag electrode, making them suitable for LTCC applications.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Ceramics
Weijia Luo, Xubin Wang, Baiheng Bai, Jianli Qiao, Xingcong Chen, Yongzheng Wen, Jingbo Sun, Lingxia Li, Ji Zhou
Summary: This study successfully establishes the relationship between internal strain and dielectric loss by synthesizing and designing specific structure of tungsten bronze ceramics, and concludes that controlling internal strain can effectively reduce dielectric loss. This research is of great significance for the development of future all-ceramic non-Hermitian devices.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2024)
Article
Chemistry, Multidisciplinary
Weijia Luo, Xubin Wang, Xingcong Chen, Siyong Zheng, Shiqiang Zhao, Yongzheng Wen, Lingxia Li, Ji Zhou
Summary: We propose a new strategy for constructing high-performance metamaterials in extreme environments by combining metamaterial design with materials optimization. By utilizing a monomeric ceramic meta-atom, we are able to achieve nearly perfect absorption with high temperature stability in the microwave/millimeter-wave bands. This breakthrough surpasses the temperature limitation of conventional plasmonic absorbers and opens up new possibilities for the development of integrated high-performance metamaterial wireless sensors.
MATERIALS HORIZONS
(2023)
Article
Chemistry, Multidisciplinary
Shun Wang, Weijia Luo, Yafeng Lu, Xubin Wang, Siyong Zheng, Runni Zhao, Lingxia Li, Ji Zhou
Summary: This study first prepared a donor-acceptor modified ZTN-CNx ceramic for constructing low-loss broadband metamaterial devices, increased the Q x f value, and designed a millimeter-wave broadband metamaterial reflector.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Materials Science, Multidisciplinary
Lingxia Li, Xubin Wang, Weijia Luo, Shun Wang, Tian Yang, Ji Zhou
Summary: A novel strategy of trivalent ion (Al3+ and Ga3+) co-substitution in tungsten bronze structural Ba4Nd9.33Ti18O54 ceramics for millimeter-wave metamaterials is proposed in this study. The results show a significant increase in Q(f) values and effective balance of miniaturization, power dissipation, and temperature stability under stable temperature characteristics.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Crystallography
Di Wu, Bei Zhang, Weijia Luo, Huaxiang Zhu, Jun Xu, Lina Zhou, Baohong Hou, Wei Chen
Summary: Two theoretical methods were employed to analyze the effects of sodium sulfate on the nucleation behavior of taurine. The higher sodium sulfate concentration increases the solid-liquid interfacial energy, changing the nucleation rate. Molecular modeling techniques showed that sodium sulfate modifies the crystal morphology of taurine.
CRYSTAL RESEARCH AND TECHNOLOGY
(2021)
Article
Materials Science, Ceramics
Dan Zhao, Yi Feng, Zhipeng Pi, Fan Zhang
Summary: Phase equilibria in the ZrO2-GdO1.5-TaO2.5 (ZGTO) system were experimentally investigated, and the differences between ZGTO and the existing ZrO2-YO1.5-TaO2.5 (ZYTO) were discussed. The study is useful for thermodynamic assessment of ZGTO and can guide the design of novel thermal barrier coatings materials.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yutaka Ohya, Wingki Mey Hendra, Chika Takai-Yamashita, Takayuki Ban
Summary: Diffusion couples of rutile and corundum single crystals were prepared and examined to study the solid solution and precipitation of corundum in rutile during cooling. Different precipitation forms of corundum were observed under different cooling conditions.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Jiaming Zhan, Yunfa Guo, Hao Wang
Summary: This study systematically investigates the mechanical behaviors of calcium fluoride in humid environments. The effects of water on the deformation and plastic enhancement of CaF2 under indentation are explored through microindentation experiments, atomic simulations, and Raman spectroscopy measurement.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Hangfeng Zhang, Henry Giddens, Theo Graves Saunders, Matteo Palma, Isaac Abrahams, Haixue Yan, Yang Hao
Summary: The relationship between low and high frequency tunabilities in tin substituted barium titanate ceramics was investigated. It was found that there are differences in tunabilities at different frequencies due to the different activities of larger ferroelectric domains and polar nanoclusters.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Kaibiao Xi, Jiacheng Liu, Beibei Song, Huarong Cheng, Yihao Li, Xiaole Yu, Mupeng Zheng, Mankang Zhu, Yudong Hou
Summary: Composite modulation in the superparaelectric state of the BTBZ-CT system is proposed as an effective strategy to achieve both NTCC and excellent energy storage performance in dielectric ceramics. The addition of BZ and CT to BT ferroelectrics can move the SPE state to the normal use temperature zone, resulting in enhanced NTCC characteristics and energy storage performance. Furthermore, intentional precipitation of CT at grain boundaries can refine the grain size, increase the bandgap, and strengthen the local electric field distribution, thereby enhancing the breakdown electric field.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Hamed Salimkhani, Lovro Fulanovic, Till Froemling
Summary: The demand for robust multilayer ceramic capacitors with high-temperature and high-power capabilities is increasing rapidly. However, cost-effective production is a challenge. This study investigates the use of Na0.5Bi0.5TiO3-based materials as promising lead-free options. By adding sintering aids, the sintering temperature of Na0.5Bi0.5TiO3-BaTiO3-CaZrO3-BiAlO3 solid solutions was successfully reduced to 975 degrees C, suitable for co-sintering with Cu electrodes without adverse effects on capacitor properties.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Mingxing Li, Ran Mo, Zeshui Xu, Jie Zhou, Conglin Zhang, Xuefeng Cui, Fang Ye, Laifei Cheng, Ralf Riedel
Summary: Polymer infiltration and pyrolysis is an effective method for preparing ceramic matrix composites. The transformation of polymer to ceramic during the process affects the residual stress and interface behavior in the composites.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yan Kang, Lin Chen, Chang-Jiu Li, Guan-Jun Yang
Summary: A novel abradable seal coating with low hardness and high bonding strength was successfully designed and prepared. This coating has significantly higher abradability and erosion resistance compared to metal-based coatings, and can retain excellent abradability and have a long lifetime during service.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Qingzhong Song, Xiangdong Zha, Ming Gao, Yingche Ma
Summary: This study analyzes the influence of calcia refractory purity on the properties of calcia crucibles. Higher purity calcia results in well-developed grains and improved hydration resistance, leading to better high-temperature strength and thermal shock resistance. In contrast, lower purity calcia crucibles exhibit inferior properties. Therefore, high-purity calcia is considered a potential refractory for manufacturing oxide crucibles.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Sehreish Abrar, Faisal Nazeer, Zhuang Ma, Ling Liu, Abdul Malik, Mustafa Kamal, Abdullah G. Al-Sehemi
Summary: To raise the operating temperature of Si-based ceramic matrix composites (CMCs), researchers have applied thermal/environmental barrier coating (T/EBCs) materials, typically rare earth silicates. However, the high thermal conductivity and the mismatch of thermal expansion have been major challenges in developing new materials that can offer thermal insulation and environmental protection to CMCs. In this study, entropy engineering was used to create a multicomponent equi-atomic single-phase pyro silicate with extremely low thermal conductivity and enhanced water vapor corrosion resistance. The research findings show the potential of high entropy disilicates in achieving ultra-low thermal conductivity and low weight loss in corrosive environments.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Zi-bo Niu, Daxin Li, Dechang Jia, Zhihua Yang, Kunpeng Lin, Paolo Colombo, Ralf Riedel, Yu Zhou
Summary: In this study, SiBCN ceramics with a special structure were prepared to improve the oxidation resistance. The effect of the structure on oxidation behavior and kinetics was investigated, revealing that the special structure can effectively inhibit heterogeneous oxidation and enhance the oxide layer composition.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Melike Donmez, Metehan Erdogan, Cihangir Duran
Summary: The limited densification of CeO2 ceramics was improved by using an anorthite-based glass, resulting in high dielectric constant and quality factor with minimum dielectric loss. The CeO2-(anorthite-based) glass ceramic showed promising results in terms of low temperature densification and microwave properties.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
S. Rahmati, R. G. A. Veiga, J. Mostaghimi, T. Coyle, A. Dolatabadi
Summary: This study provides an atomic-scale description of the high-velocity impact of alpha-Al2O3 particles onto an alpha-Al2O3 substrate during Aerosol Deposition (AD). The results suggest that the crystal orientation plays a crucial role in both plasticity and damage of the nanoparticles. Impact velocity has a direct correlation with plasticity and fragmentation, but adhesion efficiency has only a marginal increase. The crucial element lies in the substrate's surface alterations caused by the fragments left on the substrate after impact.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Bo-Wen Chen, Yan-Mei Kan, De-Wei Ni, Chun-Jing Liao, Hong-Da Wang, Yu-Sheng Ding, Shao-Ming Dong
Summary: This study characterized the long-term and repeated ablation properties of modified Cf/HfC-SiC composites with YB4-Al2O3-Si3N4 under an air plasma torch. The structural stability and viscosity of the oxide layer were found to affect the ablation resistance of the composites. By forming nano c-HfO2 grains and high-viscosity Al-Si-Y-O glassy phase, the structural stability of the oxide layer was improved, resulting in enhanced ablation resistance. However, the oxidation of Si3N4 led to the formation of NO, NO2, and excessive SiO2 glassy phase, which resulted in a porous structure and reduced the viscosity of the oxide layer. Therefore, the addition of Si3N4 decreased the ablation resistance of the composites.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yongxing Wei, Huawei Zhang, Siyuan Dong, Changqing Jin, Chenxing Bai, Junle Dai, Zengzhe Xi, Zhonghua Dai, Zengyun Jian, Li Jin
Summary: In this study, solid solutions of xBi(Ni1/2Hf1/2)O-3-(1 - x)PbTiO3 (xBNH-PT) were synthesized to investigate their phase boundary behaviors and physical properties. The presence of a tetragonal-pseudocubic phase boundary and a spontaneous ferroelectric-relaxor transition at specific compositions were confirmed. The introduction of a tetragonal-pseudocubic phase boundary improved the piezoelectric properties and suppressed the spontaneous ferroelectric-relaxor transition.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
