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Microstructure and Oxidation Behavior of ZrB_(2)-SiC Ceramics Fabricated by Tape Casting and Reactive Melt Infiltration

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无机材料学报 2024年第8期39卷 955-964页

作者： TAN Min CHEN Xiaowu YANG Jinshan ZHANG Xiangyu KAN Yanmei ZHOU Haijun XUE Yudong dong shaoming State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with *** comparison to the conventional preparation method,reactive synthesis allows for the more facile production of ultra-high temperature ceramics with fine particle size and homogeneous *** this work,ZrSi_(2),B4C,and C were used as raw materials to prepare ZrB_(2)-SiC via combination of tape casting and reactive melt infiltration herein referred to as ZBC *** sample of ZrB_(2)-SiC was also prepared using ZrB_(2) and SiC as raw materials through an identical process designated as ZS *** analysis of both ceramic groups revealed smaller and more uniformly distributed particles of the ZrB_(2) phase in ZBC ceramics compared to the larger particles in ZS *** sets of ceramics underwent cyclic oxidation testing in the air at 1600℃for a cumulative duration of 5 cycles,each cycle lasting 2 *** of the oxidation behavior showed that both ZBC ceramics and ZS ceramics developed a glassy SiO_(2)-ZrO_(2) oxide layer on their surfaces during the *** layer severed as a barrier against *** ZBC ceramics,ZrO_(2) is finely distributed in SiO_(2),whereas in ZS ceramics,larger ZrO_(2) particles coexist with glassy SiO_(2).The surface oxide layer of ZBC ceramics maintains a dense structure because the well-dispersed ZrO_(2) increases the viscosity of glassy SiO_(2),preventing its crystallization during the ***,some SiO_(2) in the oxide layer of ZS ceramics may crystallize and form a eutectic with ZrO_(2),leading to the formation of ZrSiO_(4).This leads to cracking of the oxide layer due to differences in thermal expansion coefficients,weakening its barrier *** analysis of the oxidation resistance shows that ZBC ceramics exhibit less increase in oxide layer thickness and mass compared to ZS ceramics,su

关键词： ultra-high temperature ceramic ZrB2-SiC oxidation behavior reactive melt infiltration

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结构陶瓷——承载人类文明的基石

无机材料学报 2024年第6期39卷 569-570页

作者：董绍明王京阳倪德伟中国科学院上海硅酸盐研究所上海200050 中国科学院金属研究所沈阳110016

陶瓷,作为人类文明史上具有里程碑意义的人工合成材料,不仅承载着中华民族的骄傲,更是中华民族智慧和创新精神的集中体现。经过数千年的沉淀与演化,陶瓷已发展成为一个博大精深、丰富多彩的材料体系。传统陶瓷与先进陶瓷交相辉映,共同... 详细信息

陶瓷,作为人类文明史上具有里程碑意义的人工合成材料,不仅承载着中华民族的骄傲,更是中华民族智慧和创新精神的集中体现。经过数千年的沉淀与演化,陶瓷已发展成为一个博大精深、丰富多彩的材料体系。传统陶瓷与先进陶瓷交相辉映,共同构筑起人类文明的物质基石。其中,先进结构陶瓷更是以其耐高温、抗腐蚀以及优异的力学性能等特性.

关键词：结构陶瓷先进陶瓷人工合成材料传统陶瓷力学性能抗腐蚀创新精神耐高温

Interconnected graphene scaffolds for functional gas sensors with tunable sensitivity

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Journal of Materials Science & Technology 2020年第23期58卷 16-23页

作者： Xiao You Jinshan Yang Mengmeng Wang Hongda Wang Le Gao shaoming dong State Key Laboratory of High Performance Ceramics&Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China University of Chinese Academy of Sciences Beijing100039China

In this work,the interconnected graphene scaffolds are prepared by three-dimensional(3 D)printing for multifunctional gas detection with tunable *** scaffolds with regularly aligned graphene conductive networks exhibit significant mechanical strength and high electrical stability to multi-direction deformation,which can be attributed to the typical core-shell structure of graphene and *** resistance of the free-standing scaffolds can realize the real-time response to H_(2) O and NO_(2),and the relative resistance change to 100 ppm H_(2) O and 100 ppm NO_(2) can reach 2%and 2.5%,*** charge doping of the oxidizing gases is considered to be the main reason for various response sensitivities of the scaffolds with different orthogonal layers,in which the interconnected conductive network can generate a large specific surface area and significantly improving the adsorption of the target gases and the transfer of *** controllable fabrication of regular structure has appropriately great potential for further optimizations and applications in gas detection.

关键词： Graphene scaffolds Interconnected network 3D printing Gas sensors Multifunctional gas detection

陶瓷基复合材料涡轮动叶榫头元件静强度实验及缺陷影响

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航空材料学报 2024年第4期44卷 77-84页

作者：蒋婷王子媛郭洪宝洪智亮陈小武秦浩张翔宇董绍明中国航发商用航空发动机有限责任公司先进技术研究部上海201199 中国科学院上海硅酸盐研究所上海201899

陶瓷基复合材料(ceramic matrix composites,CMC)涡轮动叶榫头是动叶装配与承受离心载荷的关键。为了研究熔渗工艺制备CMC榫头在叶片旋转径向拉伸载荷下的力学行为,验证榫头内部质量对其静拉伸强度与破坏模式的影响,设计并制备燕尾形CM... 详细信息

陶瓷基复合材料(ceramic matrix composites,CMC)涡轮动叶榫头是动叶装配与承受离心载荷的关键。为了研究熔渗工艺制备CMC榫头在叶片旋转径向拉伸载荷下的力学行为,验证榫头内部质量对其静拉伸强度与破坏模式的影响,设计并制备燕尾形CMC高压涡轮动叶榫头元件试件,对其进行单轴静态拉伸实验,采用X射线CT无损检测对实验前试件内部质量进行扫描,采用DIC与声发射方法对实验过程进行监测。结果表明:燕尾形CMC榫头在单轴静态拉伸下保持完好接触,其静态拉伸强度与破坏模式对其内部质量(尤其是分层缺陷)非常敏感。试件不含分层缺陷时,损伤起始于榫头颈部,并迅速扩展,损伤起始载荷与最大破坏载荷接近,断口呈横向锯齿状;试件内部含分层缺陷时,损伤起始于缺陷,分层逐渐扩展并导致试件断裂,损伤起始载荷下降99.05%,最大破坏载荷下降14.29%,断口位置与分层缺陷一致。

关键词：陶瓷基复合材料熔渗法涡轮动叶榫头分层缺陷

Microstructure and mechanical properties of 3D Cf/SiBCN composites fabricated by polymer infiltration and pyrolysis

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Journal of Advanced Ceramics 2021年第1期10卷 28-38页

作者： Bowen CHEN Qi DING Dewei NI Hongda WANG Yusheng DING Xiangyu ZHANG shaoming dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

In this work,three-dimensional(3D)Cf/SiBCN composites were fabricated by polymer infiltration and pyrolysis(PIP)with poly(methylvinyl)borosilazane as SiBCN *** 3D microstructure evolution process of the composites was investigated by an advanced X-ray computed tomography(XCT).The effect of dicumyl peroxide(DCP)initiator addition on the crosslinking process,microstructure evolution,and mechanical properties of the composites were *** the addition of a DCP initiator,the liquid precursor can cross-linking to solid-state at 120℃.Moreover,DCP addition decreases the release of small molecule gas during pyrolysis,leading to an improved ceramic yield 4.67 times higher than that without DCP *** 7 PIP cycles,density and open porosity of the final Cf/SiBCN composite with DCP addition are 1.73 ***^(-3)and〜10%,respectively,which are 143.0%higher and 30.3%lower compared with the composites without DCP *** a result,the flexural strength and elastic modulus of Cf/SiBCN composites with DCP addition(371 MPa and 31 GPa)are 1.74 and 1.60 times higher than that without DCP addition(213 MPa and 19.4 GPa),respectively.

关键词： Cf/SiBCN ceramic matrix composites dicumyl peroxide(DCP) X-ray computed tomography(XCT)

Effects of interfacial residual stress on mechanical behavior of SiC_(f)/SiC composites

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Journal of Advanced Ceramics 2022年第1期11卷 94-104页

作者： Xiaowu CHEN Guofeng CHENG Jinshan YANG Jianbao HU Chunjin LIAO Xiangyu ZHANG shaoming dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Analysis and Testing Center for Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Layer-structured interphase,existing between reinforcing fiber and ceramics matrix,is an indispensable constituent for fiber-reinforced ceramic composites due to its determinant role in the mechanical behavior of the ***,the interphase may suffer high residual stress because of the mismatch of thermal expansion coefficients in the constituents,and this can exert significant influence on the mechanical behavior of the ***,the residual stress in the boron nitride(BN)interphase of continuous SiC fiber-reinforced SiC composites was measured using a micro-Raman *** effects of the residual stress on the mechanical behavior of the composites were investigated by correlating the residual stress with the mechanical properties of the *** results indicate that the residual stress increases from 26.5 to 82.6 MPa in tension as the fabrication temperature of the composites rises from 1500 to 1650℃.Moreover,the increasing tensile residual stress leads to significant variation of tensile strain,tensile strength,and fiber/matrix debonding mode of the *** sublayer slipping of the interphase caused by the residual stress should be responsible for the transformation of the mechanical *** work can offer important guidance for residual stress adjustment in fiber-reinforced ceramic composites.

关键词： ceramic matrix composites Raman spectroscopy mechanical properties residual stress

Nanoinfiltration behavior of carbon nanotube based nanocomposites with enhanced mechanical and electrical properties

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Journal of Materials Science & Technology 2021年第12期71卷 23-30页

作者： Mengmeng Wang Jinshan Yang Xiao You Chunjing Liao Jingyi Yan Jing Ruan shaoming dong State Key Laboratory of High Performance Ceramics&Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China University of Chinese Academy of Sciences Beijing100039China ShanghaiTech University Shanghai201210China

In this work,carbon nanotube(CNT)based nanocomposites with high mass fraction are proposed by in-situ bridging carbon matrix into CNT paper through optimized chemical vapor infiltration(CVI).Nanoinfiltration behavior of CNTs is basically investigated under the CVI *** contact between each CNT can be strengthened and the conductive pathways can be established,resulting in the better mechanical and electrical *** with the pristine CNT paper,the CNT/C composite after pyrolysis process confirms a remarkable advance in tensile strength(up to 310±13 MPa)and Young’s modulus(up to 2.4±0.1 GPa).Besides,a notable feature of electrical conductivity also shows an improvement up to 8.5 S/cm,which can be attributed to the mass fraction of CNT(41 wt%)breaking the limits of percolation thresholds and the efficient densification of this sample to establish the conductive *** study has a broad application in the development of the multi-functional electrical and engineering materials.

关键词： Carbon nanotube Chemical vapor infiltration(CVI) Nanocomposites

Fabrication and microstructure of ZrB_2–ZrC–SiC coatings on C/C composites by reactive melt infiltration using ZrSi_2 alloy

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Journal of Advanced Ceramics 2018年第1期7卷 64-71页

作者： Chaoqiang XUE Haijun ZHOU Jianbao HU Hongda WANG Jiayue XU shaoming dong School of Materials Science and Engineering Shanghai Institute of Technology Structural Ceramics and Composites Engineering Research Center Shanghai Institute of Ceramics Chinese Academy of Sciences State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences

ZrB_2–ZrC–SiC ternary coatings on C/C composites are investigated by reactive melt infiltration of ZrSi_2 alloy into pre-coatings. Two different pre-coating structures, including porous B_4C–C and dense C/B, are designed by slurry dip and chemical vapor deposition(CVD) process respectively. The coating prepared by reactive melt infiltration(RMI) into B_4C–C presents a flat and smooth surface with a three-layer cross-sectional structure, namely interior SiC transition layer, gradient ZrB_2–ZrC–SiC layer, and ZrB_2–ZrC exterior layer. In comparison, the coating prepared by RMI into C/B shows a more granular surface with a different three-layer cross-sectional structure, interior unreacted B–C pre-coating layer, middle SiC layer, and exterior ZrB_2–ZrC–ZrSi_2 layer. The forming mechanisms of the specific microstructures in two coatings are also investigated and discussed in detail.

关键词： ultra-high temperature ceramics(UHTCs) coating reactive melt infiltration(RMI) alloy

Fabrication and efficient electromagnetic waves attenuation of three-dimensional porous reduced graphene oxide/boron nitride/silicon carbide hierarchical structures

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Journal of Materials Science & Technology 2023年第24期155卷 192-201页

作者： Qiuqi Zhang Xiao You Li Tian Mengmeng Wang Xiangyu Zhang Ying Shi Jinshan Yang shaoming dong School of Materials Science and Engineering Shanghai University Shanghai 200444 China State Key Laboratory of High Performance Ceramics & Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China University of Chinese Academy of Sciences Beijing 100049 China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 China

In this work,hierarchical hybrid composites consisting of porous three-dimensional reduced graphene oxide(3D-rGO)skeleton and lamellar boron nitride(BN)/silicon carbide(SiC)coatings are prepared by chemical vapor infiltration(CVI)*** graphene framework prepared by 3D printing and frozen self-assembly exhibits a lightweight structure and a perforated conductive network,which extends the transmission path of incident *** introduced ceramic coatings can effectively tune the impedance matching degree and supply a lossy phase,and the hierarchical structure of the composites enhances the multiple scattering of the incident *** expected,the 3D-rGO/BN/SiC composites possess an excellent absorbing performance with a minimum reflection loss value of–37.8 dB,and the widest effective absorbing bandwidth(RL<–10 dB)of 5.90 GHz is *** controllable fabrication of composites can provide a guideline for rational design and fabrication of high-performance electromagnetic waves absorbing materials in practical applications.

关键词： Porous network structure Hierarchical structure Electromagnetic wave absorbing High attenuation ability Effective absorbing bandwidth