JOURNAL OF ALLOYS AND COMPOUNDS
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2026
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IF 6.7
Muhammad Saqib,Mohsin Raza,Ali Asghar,Qumail Arshad,Muhammad Irfan Hussain,Umair Ali,Danish Ali,Cho-Pei Jiang,Zhangwei Chen
Si 3 N 4 ceramics have great potential for applications in mechatronics, biomedical implants and other advanced industries. 3D printing such as vat photopolymerization (VPP) helps the fabrication of highly complex-shaped ceramics that have not been possible with conventional manufacturing methods. However, the primary challenge is the poor dispersion and high light absorption of Si 3 N 4 powder, which leads to high slurry viscosity and limited printability. This study presents a comprehensive strategy for fabricating high-performance Si 3 N 4 ceramics via VPP by synergistically optimizing slurry formulation and sintering kinetics. We systematically engineered a 50 vol% solid loading slurry by identifying the optimal content of dispersant as 2 wt% of solid powder and the photoinitiator as 3 wt% of resin, achieving an excellent balance of low viscosity (2.58 Pa·s at 30 s −1 ) and enhanced curing depth (69 µm). The core innovation lies in uncovering the critical role of sintering heating rate on the final microstructure and properties. A detailed investigation of four heating rates (5–0.5 °C/min) at 1600°C revealed that the slowest rate (0.5 °C/min) is paramount. It promoted superior densification (64.67% relative density), controlled anisotropic shrinkage, and significantly increased three-point bending strength to 209.67 ± 2.51 MPa, a 95% improvement over the fastest rate. The work establishes that coupled optimization of rheology, curing, and most importantly, sintering thermal profile is essential for unlocking the full mechanical potential of VPP-fabricated Si 3 N 4 , providing a validated blueprint for high-performance, complex-shaped ceramic components.
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2021
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IF 5.302
Rui-Lin Lin,Wei-Chao Bao,Jun-Jie Yu,Wei-Ming Guo,Hua-Tay Lin
Based on the previous work on Si 3 N 4 -ZrB 2 , the addition of 2.5 vol.% ZrB 2 promoted α - to β -Si 3 N 4 phase transformation, bimodal microstructure, and toughness and strength improvement after hot-pressing at 1500 °C. However, the mechanism needed to be further explored. In the present work, the effect of ZrB 2 and its oxide impurities (ZrO 2 and B 2 O 3 ) on phase composition, microstructure and mechanical properties of Si 3 N 4 ceramics with MgO-Yb 2 O 3 additives were studied. Results showed that the addition of B 2 O 3 had no influence on Si 3 N 4 ceramics, whereas the addition of ZrO 2 inhibited the α - to β -Si 3 N 4 phase transformation, formed an uniform equiaxed microstructure, and deceased the toughness and strength. The positive effect of oxide impurities can be eliminated. Based on the STEM analysis , the possible reason was that the addition of ZrB 2 led to the formation of Si-Mg-O-N-Yb-Zr-B liquid phase , and then promoted α - to β -Si 3 N 4 phase transformation.
研究领域:
材料科学
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陶瓷
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机械工程
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高影响因子
MATERIALS LETTERS
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2022
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IF 3.574
Shiqin Wan,Xu Hao,Zheng Zhao,Chang Yu,Mengyi Li,Qi Wang
In this work, silicon nitride nanowires (Si 3 N 4 NWs) were successfully prepared by a modified carbothermal reduction method, using graphite felt as a growth substrate and in the absence of the catalysts. The synthesized Si 3 N 4 NWs exhibited smooth surface, uniform morphology and high aspect ratios. The high purity and high crystallinity of Si 3 N 4 NWs were confirmed by XRD , XPS , etc. More importantly, the vapor–solid (VS) growth mechanism of Si 3 N 4 NWs was proposed. It is indicated that the graphite felt played a crucial role in increasing the proportion of the gas-phase reaction to obtain large-scale Si 3 N 4 NWs. The Si 3 N 4 NWs produced by this approach have the advantages of high yield, high purity and low cost, which are very prospective for application.
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高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Wanyin Ge,Honglei Yin,Chenhui Lu,Xinmeng Zhang,Panpan Song,Mingsheng Ma,Zhifu Liu,Ye Tian
The core issue of light emitting diodes (LEDs) for actual application is the thermal stability of phosphors. Silicon nitride (Si 3 N 4 ) is generally recognized as especially important structural material due to its excellent mechanical properties at extreme high temperature. In this work, Si 3 N 4 : Eu was demonstrated to be an excellent luminescence functional material for LEDs. The discarded corner-waster silicon raw material was utilized to act as the precursor. The Si 3 N 4 :Eu phosphor was synthesized by a facile nitriding process at elevated temperature. The pure α-Si 3 N 4 :Eu nanorods were successfully obtained by adjusting the doping concentration of Eu. It is coexistence with mixed-valence (divalent and trivalent) for Eu in α-Si 3 N 4 according to X-ray photoelectron spectroscopy. The synthesized α-Si 3 N 4 :Eu nanorods showed bright yellow under the excitation of 365 nm (UV) and white luminescence by 460 nm chip (Blue). The Si 3 N 4 :Eu nanorods possess excellent thermal stability, maintains nearly 70% of the origin intensity even at temperatures over 300 °C. The Si 3 N 4 :Eu nanorods demonstrated comparable performance to commercial YAG:Ce 3+ (YAG). Moreover, the long-term thermal stability of Si 3 N 4 :Eu nanorods is superior to commercial YAG, revealing the enhanced service performance. This work not only presents a facile Si 3 N 4 :Eu nanorods green synthesis route from waste utilization, but also offers an enhanced service performance for the high temperature LEDs application.
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JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2022
·Vol. 104
·期 1
·105-115
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IF 2.606
Yang Haixia,Yue Xiandong,Ye Feng
Porous Si 3 N 4 /silica aerogel composites were prepared by sol impregnation with porous Si 3 N 4 as the framework, and the microstructure evolution and properties of the composites were studied in detail at high temperature. Porous Si 3 N 4 had a strong skeleton structure, which effectively inhibited the pore collapse of the aerogel, kept the nanostructure stable to 1100 °C, and significantly improved the temperature resistance of the silica aerogel. Preventing the growth of gel particles and pore collapse at temperatures above 1100 °C was difficult, and the silica aerogel gradually crystallised. When the temperature reached 1300 °C, the aerogel inside was completely crystallised, and the nanopore structure basically disappeared. The specific surface area of the composite decreased with increasing temperature, whereas the pore size and thermal conductivity increased with increasing temperature. The high-temperature thermal insulation performance was tested, and the composite material exhibited low thermal conductivity (0.254 W m −1 K −1 ) at even 1300 °C, which suggests this composite is suitable for thermal insulation use in a high-temperature environment.
Graphical abstract
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高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zhiyuan Ma,Huichao Cheng,Jinglian Fan,Zhenwei Wang,Zhanggen Liu
In this study, to improve the fracture toughness of Si 3 N 4 ceramics and overcome the reduction in the hardness caused by toughening, the Si 3 N 4 -based composite ceramics were prepared by spark plasma sintering . Fixed amounts of Y 2 O 3 (7 wt%) and TiC (8 wt%) together with Mo adjusted in the range of 0-8 wt% were incorporated into the Si 3 N 4 matrix. Besides, Si 3 N 4 composites were also prepared as control groups by excluding TiC and Mo. The results reveal that the addition of TiC improves the hardness of the Si 3 N 4 composites by inhibiting the transformation from α-Si 3 N 4 to β-Si 3 N 4 and grain refinement. Meanwhile, the high hardness of the composites is maintained even after toughening with Mo. The addition of Mo promotes the nucleation and phase transformation of α-Si 3 N 4 by promoting the transfer of the Si and N atoms. At the same time, molybdenum silicide is formed in-situ, improving fracture toughness through various toughening mechanisms. The Si 3 N 4 composites with 8 wt% TiC and 8 wt% Mo sintered at 1700 °C exhibit the optimal properties, with Vickers hardness and fracture toughness determined to be 18.25 GPa and 10.2 MPa•m 1/2 , respectively.
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
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IF 4.495
Weide Wang,Dongxu Yao,Hanqin Liang,Yongfeng Xia,Kaihui Zuo,Jinwei Yin,Yu-Ping Zeng
The effect of YH 2 on densification, microstructure, and thermal conductivity of Si 3 N 4 ceramics were investigated by adjusting the amount of YH 2 in the range of 0–4 wt% using a two-step sintering method. Native SiO 2 was eliminated, and Y 2 O 3 was in situ formed by a metal hydride reduction reaction, resulting in various Y 2 O 3 /SiO 2 ratios. Full densification of YH 2 -doped samples could be achieved after sintering at 1900 °C for 4 h. The Y 2 O 3 /SiO 2 ratio had a significant influence on the composition of crystalline secondary phases. Besides, the increased Y 2 O 3 /SiO 2 ratio is conducive not only to the grain growth but also to the reduction of activity of SiO 2 in the liquid phase, resulting in enlarged purified grains, reduced volume fraction of intergranular phases and increased Si 3 N 4 -Si 3 N 4 contiguity. Ultimately, the thermal conductivity increased by 29 % from 95.3 to 123.0 W m −1 K −1 after sintering at 1900 ℃ for 12 h by the substitution of Y 2 O 3 with YH 2 .
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高影响因子
CERAMICS INTERNATIONAL
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2019
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IF 3.45
Honghui Ding,Yuan Hu,Xiaolei Li,Zhihao Zhao,Huiming Ji
Porous Si 3 N 4 ceramics were fabricated by pressureless sintering at 1550 °C for 2 h with YbF 3 -MgF 2 composite sintering aids, systematically investigated for the effect of sintering aids addition on the microstructure and mechanical properties , further explored the formation process and sintering mechanism. The α-β phase transition rate of all samples approached 100% and MgF 2 showed a positive effect on the elongating of β-Si 3 N 4 crystal grains in morphology. The apparent porosity of porous Si 3 N 4 ceramics ranged from 34% to 39%. In addition, when 2.5 wt% YbF 3 was replaced by the same amount of MgF 2 , the flexural strength sharply increased to 298 MPa, an increase of ~49%, while the porosity increased to 37%, an increase of ~15%. With MgF 2 content increasing from 0 to 7.5 wt%, the structure factor reached a minimum of 3.23 when MgF 2 addition was 2.5 wt%, which demonstrated unparalleled superiority in mechanical properties compared with previous studies due to a more preferred form of morphology of connected rod-like β-Si 3 N 4 crystals network. Besides, our research indicated that MgF 2 addition could develop higher aspect ratio of β-Si 3 N 4 grains and had obviously positive effect on the elongating characteristic of β-Si 3 N 4 grains, which was related to the activation energy variation for nucleation on the different facets.
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高影响因子
COMPOSITES PART B-ENGINEERING
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2019
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IF 6.864
Shanshan Xiao,Hui Mei,Daoyang Han,Laifei Cheng
SiC nw /C/Si 3 N 4 porous ceramic composites with layer-by-layer structure were successfully fabricated by freeze drying, carbonization and chemical vapor infiltration processes for excellent room and high temperature electromagnetic (EM) wave absorption properties . The sandwich-like structure within the layer and the capacitor model structure between the layers are formed inside of the composite, and these structures are beneficial to the EM wave consumption. The EM absorption properties are optimized by regulating the relative contribution of the polarization loss (primarily provide by SiC nw and defects in carbon phase) and the conductance loss (primarily offered by the conductive network formed by the carbon thin film). As an antioxidant protective layer, Si 3 N 4 ceramic coating is prepared on the outside of the carbon film . The prepared SiC nw /C/Si 3 N 4 porous composites show high absorption efficiency (exceed −39.7 dB), wide absorption band (cover the whole X band), small density (0.92 g/cm 3 ), thin thickness (2.9 mm), and excellent high-temperature stability (stable up to 873 K). The unique structures not only facilitate EM wave absorption, but also enable the composite a compressive strength of 168 MPa.
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2018
·Vol. 101
·期 11
·4870-4875
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IF 2.956
Wei-Ming Guo,Li-Xiang Wu,Jun-Jie Yu,Ling-Yong Zeng,Shi-Kuan Sun,Jing-Xi Li,Shang-Hua Wu,Hua-Tay Lin,Cheng-Yong Wang
Based on the previous work on Si 3 N 4 –ZrB 2 [Wu et al. J Eur Ceram Soc ;2017,37:4217], the influence of ZrB 2 addition on the phase and microstructure evolution of Si 3 N 4 –ZrB 2 composites was emphatically investigated, and the mechanical properties were compared with pure Si 3 N 4 ceramics. It was revealed that the ratio of β- to (α+β)-Si 3 N 4 significantly increased from 14.3% in pure Si 3 N 4 ceramics to 39.8% in Si 3 N 4 with 15 vol% ZrB 2 addition, indicating that the introduction of ZrB 2 promoted α- to β-Si 3 N 4 phase transformation. As a consequence, the microstructure of the composite showed the bimodal distribution, containing both elongated and equiaxed Si 3 N 4 grains. For the pure Si 3 N 4 , Vickers hardness, fracture toughness and flexural strength was 22.8 GPa, 7.6 MPa m 1/2 , and 334.5 MPa, respectively. In contrast, the composite of Si 3 N 4 –30 vol% ZrB 2 simultaneously possessed an excellent combination of mechanical properties: 19.5 GPa in hardness, 9.8 MPa m 1/2 in toughness and 702.0 MPa in strength. Present study suggested that Si 3 N 4 -based ceramics with high hardness, high toughness, and high strength could be obtained by the combination of appropriate ZrB 2 content and low hot-pressing temperature.
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高影响因子
CERAMICS INTERNATIONAL
·
2017
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IF 2.986
Wenhu Hong,Shun Dong,Ping Hu,Xiaoguang Luo,Shanyi Du
Enhanced microwave absorption properties of porous PDC-SiC/Si 3 N 4 ceramics were successfully prepared through in situ growth of Si 3 N 4 nanowires (NWs) by the unidirectional freeze casting of Si 3 N 4 /camphene slurries with various polycarbosilane (PCS) contents at 1400 °C in N 2 . Si 3 N 4 NWs were in situ formed in the pore channels via a vapor-solid (VS) mechanism, the content of Si 3 N 4 NWs increased with increasing of PCS content, which tailored the microstructure and mechanical property of porous PDC-SiC/Si 3 N 4 ceramics. With the increase of PCS content, the minimum reflection coefficient (RC) of porous PDC-SiC/Si 3 N 4 ceramic decreased from −20.2 dB to −56.2 dB, and the effective absorption bandwidth (EAB) increased from 5.3 to 7 GHz, demonstrating that the porous PDC-SiC/Si 3 N 4 ceramics decorated with Si 3 N 4 NWs had a superior microwave-absorbing ability, which could be ascribed to the electronic dipole polarization and interfacial scattering enhanced by the various interfaces among Si 3 N 4 , in-situ formed PDC-SiC nanograins, nanosized carbon and Si 3 N 4 NWs phases. These findings provide significance guidance in the development of new broadband EM absorbing materials.
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高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qingxuan Zhou,Yang Wang,Zhuoqun Han,Jia Liu,Jie Zhao,Wei Chu,Zhicheng Zhao,Jian Li,Zhiqiang Cheng,Ling Li,Futian Liu
Due to the low powder content characteristic of digital light processing in the preparation of ceramic green bodies, significant challenges arise in obtaining high-density, high-performance Si 3 N 4 ceramic. Sintering aids exert a critical influence on the densification and properties of Si 3 N 4 ceramics. To further improve the performance of 3D-printed Si 3 N 4 ceramics, Si 3 N 4 ceramics were fabricated using DLP technology combined with gas pressure sintering employing different ratios of La 2 O 3 -MgO as sintering aids. The ceramic slurries, microstructures, and ceramic performance were studied systematically. The results showed that increasing the proportion of· La 2 O 3 powder enhanced the rheological and curing properties of Si 3 N 4 ceramic slurries. Varying the La 2 O 3 -MgO ratio affected the composition of the liquid phase, leading to differences in the densification and grain growth of Si 3 N 4 ceramics. The average grain size increased with higher ratios of La 2 O 3 -MgO, and reached a maximum value of 0.91 μm with a ratio of 9:1. With the increase of the La 2 O 3 -MgO ratio, the bulk density and shrinkage rate of the ceramics initially increased and then declined. In addition, the flexural strength and fracture toughness of the ceramics peaked at a ratio of 3:7 for La 2 O 3 -MgO, measuring 577 ± 16.28 MPa and 5.84 ± 0.17 MPa m 1/2 , respectively. These results demonstrate that high-performance Si 3 N 4 ceramics can be effectively prepared using DLP technology by adapting the ratio of sintering additives.
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高影响因子
危险品化学品经营许可证（带存储）