CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhongya Zhang,Lijuan Zhang,Guangwu Wen,Yongzhao Hou,Nannan Zhu,Cheng Zhong,Jing Xue,Chuncheng Wei,Shuang Li
In this paper, polysilazane photocurable slurry with low viscosity and excellent rheological properties was prepared with β-Si 3 N 4 filler. Digital light processing (DLP) technique was utilised to form green bodies through optimized printing parameters. It was found that the introduction of β-Si 3 N 4 filler reduced the shrinkage and improved the mechanical properties of the polysilazane derived SiCN ceramics. The flexural strength of the resulted ceramics reached a maximum of 253.0 ± 15.1 MPa while 20 wt% of β-Si 3 N 4 powder was added, and the fracture toughness increased to 3.1 ± 0.3 MPa m 1/2 at 30 wt% of the β-Si 3 N 4 powder addition. The shape of the introduced β-Si 3 N 4 particles were believed to be faveriable for uniform dispersion in the printing slurry without agglomeration. In the following pyrolysis treament the β-Si 3 N 4 powders promoted the release of gaseous products so that maintained the structure integrety of the printed parts and the rod-like β-Si 3 N 4 particles enhanced the energy dissipation during ceramic fracture. In this study, silicon-based composite of β-Si 3 N 4 /SiCN ceramics with excellent mechanical properties were prepared by DLP additive manufacturing technology, which confirmed the feasibility and the great potential of photo-curing additive manufacturing technology in the manufacturing of SiCN ceramic matrix composites with complex structures.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2021
·
IF 5.039
Bing Liu,Chun-miao Du,Yong-zhen Zheng,Gui-yong Xiao,Chuan-zhong Chen,Yu-peng Lu
The effect of nano-scaled Si 3 N 4 particles on the microstructure, mechanical and electrochemical behavior of hopeite (Zn 3 (PO 4 ) 2 ·4H 2 O) conversion coating on pure titanium was investigated. Different concentrations of nanoparticles were dispersed into the phosphating bath to incorporate the process of coating deposition. The XRD results demonstrated that nano-Si 3 N 4 were doped into the coatings without any decomposition or reaction with the hopeite phase. A finer and denser microstructure of the composite coating could be obtained at the addition of 0.5 g/L Si 3 N 4 in comparison with the pure hopeite coating. Moreover, the composite coating presented a higher bonding strength and corrosion resistance related to the refinement of microstructure and filling of the embedded nanoparticles. It is suggested that the incorporation of nano-Si 3 N 4 particles in conversion coating is a promising approach for performance optimization.
研究领域:
材料科学
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电化学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Gaoxi Cui,Tongyang Li,Ziyue Wang,Lujie Wang,Yuan Yu,Huaguo Tang,Zhuhui Qiao
Soft metal as the second phase to enhance the mechanical and tribological properties of Si 3 N 4 ceramics was a focus of current research. Limited by the doping method and the low melting point of the metal, there were often phenomena such as nonuniform distribution and melting overflow of the second phase, which seriously deteriorated the properties of Si 3 N 4 . In this study, Cu-containing Si 3 N 4 was prepared by in-situ method using copper citrate as the second phase additive. The highly dispersed second phase helped Si 3 N 4 achieve significant improvements in fracture toughness and tribological properties. The phase composition, microstructure, hardness, fracture toughness, and tribological properties of Cu-containing Si 3 N 4 were investigated. XRD results indicated that the reinforcement phase was in the form of Cu 3 Si. When the Cu 3 Si phase content was 3 wt%, the fracture toughness of Cu-containing Si 3 N 4 could be increased by 27.1 % compared to the Si 3 N 4 . When the Cu 3 Si phase content reached 12 wt%, the wear rate at room temperature was reduced by 59 % compared to the substrate. The toughing mechanism could be summarized as the crack bridging and deflection of the Cu 3 Si phase. The anti-wear mechanism could be concluded as the reduction of micro-cracks in the friction film with the participation of Cu 3 Si phase, thus reducing the loss in the friction process.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yuelong Wang,Jianjun Tian,Haoyang Wu,Baorui Jia,Xingyu Li,Yiming Zhang,Zhirui Zhang,Xuanhui Qu,Mingli Qin
Si 3 N 4 ceramics were prepared using novel two-step sintering method by mixing α -Si 3 N 4 as raw material with nanoscale Y 2 O 3 –MgO via Y(NO 3 ) 3 and Mg(NO 3 ) 2 solutions. Si 3 N 4 composite powders with in situ uniformly distributed Y 2 O 3 –MgO were obtained through solid–liquid (SL) mixing route. Two-step sintering method consisted of pre-deoxidization at low temperature via volatilization of in situ-formed MgSiO 3 and densification at high temperature. Variations in O, Y, and Mg contents in Si 3 N 4 –Y 2 O 3 –MgO during first sintering step are discussed. O and Mg contents decreased with increasing temperature because SiO 2 on Si 3 N 4 surface reacted with MgO to form low-melting-point MgSiO 3 compound, which is prone to volatilize at high temperature. By contrast, Y content hardly changed due to high-temperature stability of Y–Si–O–N quaternary compound. In the second sintering step, skeleton body was densified, and the formation of Y 2 Si 3 O 3 N 4 secondary phase occurred simultaneously. Two-step sintered Si 3 N 4 ceramics had lower total oxygen content (1.85 wt%) than one-step sintered Si 3 N 4 ceramics (2.51 wt%). Therefore, flexural strength (812 MPa), thermal conductivity (92.1 W/m·K), and fracture toughness (7.6 MPa⋅m 1/2 ) of Si 3 N 4 ceramics prepared via two-step sintering increased by 28.7%, 16.9%, and 31.6%, respectively, compared with those of one-step sintered Si 3 N 4 ceramics.
研究领域:
材料科学
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机械工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Houbao Liu,Wei Wang,Zhenbang Cheng
Effective thermal management materials are crucial for modern electronics, aerospace, and energy applications. This study investigates a novel approach by constructing a Si₃N₄ skeleton with a triply periodic minimal surface (TPMS) structure and reinforcing phase change materials (PCM) with boron nitride (BN) to develop Si₃N₄@BN/PCM composites that exhibit enhanced thermal conductivity, thermal stability and electrical insulation. Utilizing digital light processing 3D printing, a Si₃N₄ TPMS structure was prepared and subsequently reinforced with BN via vacuum-assisted infiltration into PCM. The incorporation of 3D Si₃N₄ skeleton and 2D BN flakes created a dual-scale network within the PCM, significantly increasing thermal conductivity from 0.24 W/m·K to 2.04 W/m·K. The presence of Si₃N₄ and BN notably improved thermal stability and reduced the coefficient of thermal expansion. Additionally, electrical insulation properties improved with an increase in volume resistivity and breakdown strength to 5.1 × 10 1 ⁴ Ω·cm and 62.4 kV/mm, respectively. This work demonstrates that Si₃N₄@BN/PCM composites effectively integrate high thermal conductivity, stability, and electrical insulation, thereby meeting the stringent demands of thermal management applications.
研究领域:
材料科学
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热能工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Feng Wang,Jinwei Yin,Dongxu Yao,Yongfeng Xia,Kaihui Zuo,Hanqin Liang,YuPing Zeng
Porous Si 3 N 4 ceramics were fabricated through gelcasting followed by pressureless sinter at 1690 °C. Oil-in-water (O/W) Si 3 N 4 suspensions were prepared by mixing paraffin O/W emulsion and Si 3 N 4 suspensions, sodium alginate was used as gelling agent. The casted suspensions were quickly gelled by spraying calcium chloride aqueous solution onto the surface, thus oil was enwrapped into the green bodies. The porous Si 3 N 4 ceramics had spherical-shaped pores both with and without adding O/W emulsion. As changing the O/W emulsion content in the suspension, porous Si 3 N 4 ceramics with high open porosity of 60.1–63.9% and flexural strength of 44.5–34.6 MPa were obtained.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2023
·Vol. 20
·期 6
·3754-3765
·
IF 2.1
Quan Li,Zhicheng Wang,Yang Wang,Jian Yang
High-density Si 3 N 4 -SiC ceramic nanocomposites have exceptional mechanical properties, but little is known about their electromagnetic wave absorption (EMA) capabilities. In this paper, the effects of sintering temperature and starting material compositions on the dielectric and EMA properties of hot-pressed Si 3 N 4 -SiC ceramic nanocomposites were investigated. The real and imaginary permittivities of Si 3 N 4 -SiC ceramic nanocomposites increase with increasing sintering temperature or SiC content, particularly at the sintering temperature of 1850°C and SiC content of 50 wt.%. This is primarily due to the improvement of interfacial and defect polarizations, which is caused by the doping of nitrogen into the SiC nanocrystals during the solution-precipitation process. The real and imaginary permittivities of Si 3 N 4 -SiC ceramic nanocomposites show decreasing trends as sintering aid content increases. Si 3 N 4 -SiC ceramic composites have both good EMA and mechanical properties when they are sintered at 1850°C with 30 wt.% SiC and 5–8 wt.% sintering aids. The minimum reflection loss and maximum flexural strength reach -58 dB and 586 MPa, respectively. Materials with multilayered structural designs have both strong and broad EMA properties.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2024
·
IF 1.8
Zhuoqun Han,Jia Liu,Weiwei Wang,Qingxuan Zhou,Zhicheng Zhao,Yongning Han,Yingying Wang,Yang Wang,Futian Liu,Ling Li
Si 3 N 4 ceramics with high mechanical properties and thermal conductivity, exhibiting fine and bimodal microstructure, were prepared by adjusting the Er 2 O 3 /MgO ratio and hot-pressing sintering at 1800°C for 4 h. The microstructure, grain distribution, lattice oxygen content, mechanical properties, and crack propagation process of the sintered bulk samples were systematically investigated. It was found that a low Er 2 O 3 /MgO ratio contributed to the densification of Si 3 N 4 ceramics, whereas a high Er 2 O 3 /MgO ratio favored the grain growth of Si 3 N 4 ceramics. In this research, the grain size distribution and average diameters as well as their impact on mechanical properties were examined. When the ratio of Er 2 O 3 /MgO was 3:1, Si 3 N 4 had a larger average diameter and higher thermal conductivity, but the mechanical properties were somewhat reduced. When the ratio of Er 2 O 3 /MgO was 2:2, the sample displayed enhanced mechanical performance, which can be explained by the formation of a bimodal structure. The research indicates that it is feasible to control the microstructure and optimize the mechanical properties of Si 3 N 4 ceramics by tailoring the sintering additives.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
KEY ENGINEERING MATERIALS
·
2016
·
IF 0
Ping Ping Zhang,Hong Sheng Wang,Ling Li,Lai Lv,Qing Li Zhang
The vacuum-sintering technology was adopted to prepared Si3N4-SiC composite ceramic, a type of Radar Wave-Absorbing materials (RAW). The mechanical performances of the composite materials were tested and the influences of SiC powers on the mechanics performances and microstructure of Si3N4 ceramics were investigated. The results show that the sintering density, the content of size ofβ-Si3N4 and the strength of Si3N4-SiC all decrease along with the increase of SiC powers in sample, compared with the pure matrix Si3N4 .Meanwhile, Relationship between SiC content and relative permittivity of Si3N4-SiC within the frequency range of 8.2–12.4 GHz (X-band) was studied. The average of relative permittivityεof Si3N4-SiC increased from 7.878 to 13.88 and the average of dielectric loss tanδincreased from 5.6×10-3 to 0.7869 when the content of SiC increased from 0 to 15 wt.%. The excellent microwave absorbing abilities of Si3N4–SiC ceramic were attributed to the interfacial polarization at interface between Si3N4 and SiC and at grain boundary between SiC nanocrystals.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xuanzhi Chen,Yehua Li,Youwu Liu,Pengjin Huang,Haidong Wu,Shanghua Wu,Xin Deng
Si 3 N 4 ceramics were sintered at 1850 °C and 2 MPa in a nitrogen atmosphere, using Gd 3 Si 2 C 2 -MgO as a sintering aid. The impact of Gd 3 Si 2 C 2 content and sintering dwell time at 1850 °C on the relative density, microstructure, and thermal conductivity of the Si 3 N 4 ceramics was investigated. The results indicate that under 4 h of sintering, increasing Gd 3 Si 2 C 2 content significantly enlarges Si 3 N 4 grain size while reducing microstructural uniformity; however, after 8 h, grain size refines and uniformity markedly improves. This phenomenon is mainly attributed to the increase in Gd 3 Si 2 C 2 content, which raises the number of β-Si 3 N 4 nucleation sites, thereby facilitating grain growth during short-term sintering; whereas during long-term sintering, the further enlarged grains generate a spatial hindrance effect, promoting the homogenization of the microstructure. Furthermore, under the same Gd 3 Si 2 C 2 content, extending the sintering time is beneficial to the growth of silicon nitride grains and the reduction of the glass phase, enhancing the continuity of Si 3 N 4 /Si 3 N 4 interfaces and thereby improving the thermal conductivity of Si 3 N 4 ceramics. The maximum thermal conductivity of 107.25 W·m −1 ·K −1 was achieved with a Gd 3 Si 2 C 2 content of 1 mol% and a sintering period of 8 h at 1850 °C.
研究领域:
材料科学
·
陶瓷
·
热性能
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 19
·194001
·
IF 3.551
Bo Wang,Xin Huang,Xiao-Nan Zhou,Qiang Zhi,Liu-Cheng Hao,Zi-Xuan Li,Shan Zhao,Bao-Qiang Hou,Jian-Feng Yang,Kozo Ishizaki
One-dimensional Si3N4 nanostructures are desirable for constructing nanoscale electric and optoelectronic devices due to their peculiar morphologies. Herein, a facile and environmentally friendly catalyst-free method is proposed to synthesize ultra-long single crystal α-Si3N4 nanobelts via carbothermal nitridation of carbon nanotubes at 1750 °C. The obtained α-Si3N4 nanobelts with a flat surface (thickness of ∼150 nm, length of several millimeters) exhibited an extremely high aspect ratio, perfect crystal structure, and high specific surface area of 7.34–10.09 m2 g−1. In addition, the width was increased from approximately 80 nm to 8 μm by increasing the holding time from 1 to 3 h. The nanobelt formation was governed by the vapor–solid (VS) reaction between SiO vapor, N2 and carbon nanotubes, and the vapor–vapor reaction between SiO, CO and N2. The former was responsible for the initial nucleation and successive base-growth of α-Si3N4 nanotubes. The latter additionally contributed to the nanorod and subsequent proto-nanobelt formation and to the growth of the nanobelts. During high-temperature annealing at 1750 °C, the original Si3N4 nanotubes gradually transformed into nanorods, and, finally, nanobelts with stable shapes as a result of surface energy minimization.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Applied Ceramic Technology
·
2021
·Vol. 18
·期 4
·1183-1191
·
IF 1.968
Sen Wang,Feng Liang,Saisai Li,Liang Tian,Shaowei Zhang,Quanli Jia,Shuai Chang,Sheng Yan,Haijun Zhang
Monophase α-Si 3 N 4 was prepared by a salt melt strategy using Si as a starting material. The results showed that molten salt enhanced the conversion of Si to monophase α-Si 3 N 4 , and some as-synthesized α-Si 3 N 4 nanoparticles had a hexagonal platelet morphology. The α-Si 3 N 4 hexagonal nanoplatelets had an average lateral dimension of about 170 nm and a thickness of about 5.2 nm. The nitridation of Si in molten salt was investigated by a thermal quenching method, and the silicon halide intermediate products were detected by X-ray photoelectron spectroscopy. Silicon halides possessing higher reactive activity facilitated the nitridation of Si and nucleation of α-Si 3 N 4 . Furthermore, the lattice mismatch between α-Si 3 N 4 and the salts was calculated, suggesting that the lateral growth of α-Si 3 N 4 nanoplatelets had been guided by the salt crystal structure. Based on the results, the relevant formation mechanism of α-Si 3 N 4 nanoplatelets was proposed.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）