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Enhanced wetting and properties of carbon/carbon-Cu composites with Cr_3C_2 coatings by Cr-solution immersion method

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Journal of Materials Science & Technology 2018年第3期34卷 458-465页

作者： Bo Kong Jinming Ru Hongdi Zhang tongxiang fan State Key Laboratory for Metal Matrix Composite Shanghai Jiaotong University Institute of Advanced Manufacturing and Modern Equipment Technology Jiangsu University

A facile ammonium-dichromate solution immersion method was introduced to synthesize the copperwettable Cr3C2 coating on and inside the carbon-carbon （C/C） preform. The formation mechanism and the microstructures of the Cr3C2 coatings were studied. The contact angle between molten copper and the C/C decreased from 140°to 60°, demonstrating the significant improvement in the wettability. The Cr3C2- coated C/C-Cu composite with only 4.2% porosity and 3.69 gcm^-3 density was manufactured through copper infiltration. As a result, the thermal and electrical conductivity of the modified C/C-Cu increased significantly due to the infiltrated copper. Also the mechanical properties of the composites including both the flexural and compressive strengths were enhanced by over 100%. The modified C/C-Cu composite exhibited lower friction coefficients and wear rates for different load levels than those of the commercial C/Cu composite. These results demonstrate the potential of the modified C/C-Cu material for use in electrical contacts.

关键词： Enhanced wetting and properties of carbon/carbon-Cu composites with Cr3C2 coatings by Cr-solution immersion method Cr Cu

EFFECT OF SILICON CARBIDE VOLUME FRACTION UPON INTERFACE REACTION IN SiC_p/Al COMPOSITES

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中国有色金属学会会刊：英文版 1999年第2期9卷 158-163页

作者： fan, tongxiang Shi, Zhongliang Zhang, Di Wu, Renjie Shanghai Jiao Tong Univ Shanghai China

１ＩＮＴＲＯＤＵＣＴＩＯＮＤｉｓｃｏｎｔｉｎｕｏｕｓｌｙｒｅｉｎｆｏｒｃｅｄｍｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓａｒｅｖｅｒｙａｔｒａｃｔｉｖｅｉｎａｅｒｏｓｐａｃｅａｎｄａｕｔｏｍｏｔｉｖｅｉｎｄｕｓｔｒｙｆ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＤｉｓｃｏｎｔｉｎｕｏｕｓｌｙｒｅｉｎｆｏｒｃｅｄｍｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓａｒｅｖｅｒｙａｔｒａｃｔｉｖｅｉｎａｅｒｏｓｐａｃｅａｎｄａｕｔｏｍｏｔｉｖｅｉｎｄｕｓｔｒｙｆｏｒｔｈｅｉｒｐｒｏｐｅｒｔｉｅｓ...

关键词： SiCp/Al compositeremelting recyclinginterface reactionreinforcement volume

Electron theory analysis about the influence of Cr and Mn on the carbide spheroidization by heat treatment

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Chinese Science Bulletin 1998年第15期43卷 1312-1317页

作者： Yifu Ye tongxiang fan Yuxia Shang Shandong Univ Technol Coll Mat Sci & Engn Jinan 250061 Peoples R China Shanghai Jiao Tong Univ Inst Composite Mat Shanghai 200030 Peoples R China

It is found that the distribution of covalent electron pair number and covalent bond energy was nonuniform in carbides Fe 3C, (Fe,Cr) 3C and (Fe,Mn) 3C, in which the energy difference between the strongest and the weakest bonds is very great. A criterion of covalent bond breaking during the heat treatment of M 3C pattern carbide is presented as follows. If the heat energy \%E\-\%w from heat treatment is higher than the diffusion activation energy \%Q\% of carbon atom in γ_Fe, the less the covalent bond energy \%E\% α is, the earlier the covalent bond α will be broken. According to the criterion, why the breaking of (Fe,Mn) 3C network was easier than that of Fe 3C network and why the breaking of (Fe, Cr) 3C network was more difficult than that of Fe 3C network are explained. It is indicated that Mn promoted the carbide to be spheroidized and Cr hindered the carbide from spheroidization during the heat treatment of carbides spheroidization.

关键词： M 3C pattern carbide carbide spheroidization valence electron structure.

Significant strengthening of copper-based composites using boron nitride nanotubes

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1764-1778页

作者： Naiqi Chen Quan Li Youcao Ma Kunming Yang Jian Song Yue Liu tongxiang fan State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Institute of Materials China Academy of Engineering PhysicsMianyang 621900China

Nanotubes, such as boron nitride nanotubes (BNNTs) and carbon nanotubes (CNTs), exhibit excellent mechanical properties. In this work, high-quality BNNTs were synthesized by ball milling and annealing. Subsequently, well-dispersed 3vol%BNNTs/Cu and 3vol%CNTs/Cu composites were successfully prepared using ball milling, spark plasma sintering, and followed by hot-rolling. Moreover, the mechanical properties and strengthening mechanisms of BNNTs/Cu and CNTs/Cu composites were compared and discussed in details. At 293 K,both BNNTs/Cu and CNTs/Cu composites exhibited similar ultimate tensile strength (UTS) of~404 MPa, which is approximately 170%higher than pure Cu. However, at 873 K, the UTS and yield strength of BNNTs/Cu are 27%and 29%higher than those of CNTs/Cu, *** difference can be attributed to the stronger inter-walls shear resistance, higher thermomechanical stability of BNNTs, and stronger bonding at the BNNTs/Cu interface as compared to the CNTs/Cu interface. These findings provide valuable insights into the potential of BNNTs as an excellent reinforcement for metal matrix composites, particularly at high temperature.

关键词： boron nitride nanotubes copper matrix composites excellent mechanical property strengthening mechanism

Growth kinetics of titanium carbide coating by molten salt synthesis process on graphite sheet surface

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1858-1864页

作者： Xiaoyu Shi Chongxiao Guo Jiamiao Ni Songsong Yao Liqiang Wang Yue Liu tongxiang fan State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective *** study investigates the reaction process and growth kinetics involved in MSS,shedding light on key aspects of the *** involvement of Ti powder through liquid-phase mass transfer is revealed,where the diffusion distance and quantity of Ti powder play a crucial role in determining the reaction rate by influencing the C content gradient on both sides of the ***,the growth kinetics of the carbide coating are predominantly governed by the diffusion behavior of C within the carbide layer,rather than the chemical reaction *** analyze the kinetics,the thickness of the carbide layer is measured with respect to heat treatment time and temperature,unveiling a parabolic relationship within the temperature range of 700-1300℃.The estimated activation energy for the reaction is determined to be 179283 J·mol^(-1).These findings offer valuable insights into the synthesis of carbide coatings via MSS,facilitating their optimization and enhancing our understanding of their growth mechanisms and properties for various applications.

关键词： titanium carbide graphite molten salt kinetic analysis

KOH-assisted aqueous synthesis of bimetallic metal-organic frameworks and their derived selenide composites for efficient lithium storage

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 601-610页

作者： Shuya Zhang Yanchun Xue Yutang Zhang Chengxing Zhu Xingmei Guo Fu Cao Xiangjun Zheng Qinghong Kong Junhao Zhang tongxiang fan School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200240China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China Foshan(Southern China)Institute for New Materials Foshan 528200China

To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)*** them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly *** assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 *** is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.

关键词： potassium hydroxide assisted aqueous strategy bimetallic zeolitic imidazolate frameworks bimetallic selenide lithium-ion batteries long cycle performance

金属/陶瓷润湿性的实验表征和理论预测研究进展

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材料导报 2019年第21期33卷 3606-3612页

作者：屈伟范同祥上海交通大学金属基复合材料国家重点实验室

金属/陶瓷体系的润湿性研究在金属与陶瓷的连接、金属液的熔炼和提纯、浸渗法和液相法制备复合材料等领域都有着重要意义。金属熔体在陶瓷表面的润湿过程中,会出现基板在熔体中溶解、界面吸附和互相反应等,是一种较为复杂的物理化学现... 详细信息

金属/陶瓷体系的润湿性研究在金属与陶瓷的连接、金属液的熔炼和提纯、浸渗法和液相法制备复合材料等领域都有着重要意义。金属熔体在陶瓷表面的润湿过程中,会出现基板在熔体中溶解、界面吸附和互相反应等,是一种较为复杂的物理化学现象。有关金属/陶瓷润湿性的实验和理论研究一直是国际上材料学领域的热点之一。目前金属/陶瓷润湿性主要通过测量接触角θ(借助Young’s方程计算)来得出,润湿性表征方法存在较大局限性,特别是接触角对实验条件高度敏感,其往往难以准确反映润湿性,以及适用于高熔点合金与陶瓷体系的方法较为缺乏。因此,除对接触角测试方法进行改进外,很多研究者也试图通过理论计算来考察润湿性,但至今尚未发展出能够很好地应用于所有金属/陶瓷体系的理论预测模型。润湿性实验表征方法的近期研究主要集中在改良座滴法、滴定法、毛细上升法和感应熔化法等。其中,改良座滴法相比传统座滴法能够消除熔体表面氧化膜的影响。感应熔化法可以使高熔点合金(如Ti合金等)熔化,具有独特优势(相比之下其他几种方法只适用于Al系、Mg系等低熔点合金与陶瓷的体系)。在理论预测模型方面,除直接基于Young’s方程,根据表面张力模型来研究润湿性外,也有学者尝试结合YoungDupré方程,从热力学和原子键的角度揭示反应界面润湿性的内在规律。同时,将润湿视为一种反应现象,对界面反应吉布斯自由能变化和润湿过程中表面相的能量变化加以考虑,也形成了一种新的定性衡量润湿性的标准。此外,研究者还在润湿铺展动力学方面取得了一些重要成果,包括直接根据金属形核理论来计算润湿角,以及利用如流体动力学模型、分子动力学模型、反应控制模型和扩散控制模型等来预测金属/陶瓷体系的润湿速率。本文主要从润湿过程的机制、接触角的测试方法和用以预测润湿性的理论模型三个方面,综述了金属/陶瓷润湿性领域的实验和理论研究进展。

关键词：润湿金属/陶瓷界面接触角理论模型毛细上升法感应熔化法表面张力模型润湿铺展动力学

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液/固晶面润湿性实验与模拟研究方法

材料导报 2022年第9期36卷 139-150页

作者：郑棋文范同祥上海交通大学金属基复合材料国家重点实验室

液/固晶面润湿问题在钎焊、金属基复合材料液相法制备等领域都有着重要研究意义。研究发现，固体晶面结构会显著影响液/固界面润湿性。研究液体在固体特定晶面上的润湿行为，对于深入理解润湿过程及更有针对性地改善材料液/固界面润湿... 详细信息

液/固晶面润湿问题在钎焊、金属基复合材料液相法制备等领域都有着重要研究意义。研究发现，固体晶面结构会显著影响液/固界面润湿性。研究液体在固体特定晶面上的润湿行为，对于深入理解润湿过程及更有针对性地改善材料液/固界面润湿性具有重要意义。目前研究液/固晶面润湿性的实验测量方法主要为座滴法，然而该方法针对强弱界面结合体系的测量结果对实验条件均较敏感，且受限于特定晶面基板是否容易制备，因此仍不能在液/固晶面润湿性的研究中推广采用。微观模拟方法不仅可以建立不同晶面的固体结构，同时有效避免了实验条件的影响，故对预测实验结果具有独特的优势。用于液/固晶面润湿性研究的微观尺度模拟方法包括分子动力学、第一性原理计算以及Ab-initio分子动力学。目前分子动力学方法主要应用于强界面结合的金属/金属体系，通过模拟实际物理条件下的熔化和润湿过程，可研究润湿性、界面反应、铺展动力学以及探究温度对润湿的影响，然而有效势函数的缺乏限制了该方法在其他体系的推广，且势计算结果的准确性与可靠性严重依赖势函数的参数选择。电子尺度的第一性原理计算可探究弱界面结合体系中不同晶面取向下润湿性差异的根本原因、强界面结合体系中界面微观构型对初始润湿性的影响、反应后熔体/反应产物界面成键特点以及平衡润湿性差异，但是该方法的缺点是计算原子个数有限，需要绝对零度的模拟温度。Ab-initio分子动力学是前两种方法的结合，虽然不依赖于势函数的参数选择，但是仍受限于计算原子个数和模拟效率。本文从每种方法的基本原理、实验操作或模型构建及优缺点等三个方面，阐述了弱/强界面结合体系中液/固晶面润湿性研究进展，并对三种微观模拟方法的未来改进方向进行了展望。

关键词：液/固界面润湿晶面结构实验测量分子动力学第一性原理 Ab-initio分子动力学

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铸造耐热铝合金的研究进展及展望

材料导报 2022年第2期36卷 153-161页

作者：张华炜刘悦范同祥上海交通大学金属基复合材料国家重点实验室

随着资源和环境问题日益突出,世界各国均对汽车工业节能减排提出了迫切的要求。用铸造耐热铝合金替代铸铁可大幅度减轻车身质量因此铸造耐热铝合金成为新一代汽车发动机缸体和活塞的主流材料。然而,商业铸造铝合金的高温性能并不能较好... 详细信息

随着资源和环境问题日益突出,世界各国均对汽车工业节能减排提出了迫切的要求。用铸造耐热铝合金替代铸铁可大幅度减轻车身质量因此铸造耐热铝合金成为新一代汽车发动机缸体和活塞的主流材料。然而,商业铸造铝合金的高温性能并不能较好地满足当前应用需求,并且快速凝固铝合金和铝基复合材料受限于高昂成本和制备复杂性而不能被大范围推广。因此,目前学术界和产业界的研究多集中于铸造铝合金耐热性能的提升和新型高温强化机理的探索。铸造耐热铝合金可分为三个体系:Al-Si、Al-Cu和Al-Mg。其中,Al-Si合金因具备优异的铸造流动性等成型特性而被大范围研究和应用。通过添加多种元素进行合金化,在铝合金中形成各种熔点高、热稳定性好的金属间化合物阻碍晶界运动和位错滑移是目前主流的强化方式。而经过热处理和Si相变质,进一步调控合金的组织结构也是一种重要的强化手段。此外,优化熔炼和铸造工艺,减少夹杂和铸造缺陷对提高铸造铝合金的高温强度也有重要意义。值得注意的是,近年来的研究表明第二相的三维网状互联结构与合金高温性能的提升存在密切关系。在高温强度以外,国内外学者也致力于研究铸造铝合金的蠕变性能、疲劳性能和热暴露性能。本文从体系组成和国内外商用产品两方面归纳了铸造耐热铝合金的发展和应用,分析了铸造铝合金组织结构调控的基本手段,总结了铸造铝合金高温性能的最新研究成果,同时对铸造耐热铝合金的未来研究方向进行了展望。

关键词：铸造铝合金耐热铝合金合金化热处理高温性能