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Investigation of Nanocrystalline Fe-Cu-Nb-Mo-si-B Alloy

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Journal of Materials Science & Technology 1997年第5期13卷 425-430页

作者： Zhang Y. Shanghai Iron and Steel Research Institute Shanghai 200940 China

The soft magnetic properties are reported for newly-developed nanocrystalline Fe72.7Cu1Nb1.8-Mo2si13B9.5 and Fe73Cu1Nb1.5Mo2si13B9.5 The high frequency core losses of the new alloys are as follows: P-3/100K=473 kW.m(-3), P-2/200K=750 kW.m(-3), P-2/500K=3400 kW.m(-3), P-0.5/1000K 680 kW.m(-3), which are clearly lower than those of the early-developed Fe-Cu-Nb-si-B nanocrystalline alloys and the superior power MnZn ferrite H-7c4 The dependences of core loss on frequency and amplitude magnetic flux density have been analysed. The temperature relations of initial susceptibility have been examined for as-quenched and different annealed Fe72.7Cu1Nb1.8Mo2si13B9.5 alloy acid interpreted by using the phenomenological theory.

关键词： Mo Fe si Cu

si nanoparticles seeded in carbon-coated Sn nanowires as an anode for high-energy and high-rate lithium-ion batteries

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Materials Futures 2022年第1期1卷 113-121页

作者： Liubin Ben Jin Zhou Hongxiang Ji Hailong Yu Wenwu Zhao Xuejie Huang Songshan Lake Materials Laboratory Dongguan 523808Guangdong ProvincePeople’s Republic of China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

High-capacity and high-rate anode materials are desperately desired for applications in the next generation lithium-ion batteries.Here,we report preparation of an anode showing a structure of si nanoparticles wrapped inside Sn nanowires.This anode inherits the advantages of both si and Sn,endowing lithiation/delithiation of si nanoparticles inside the conducting networks of Sn nanowires.It demonstrates a high and reversible capacity of∼1500 mAh g−1 over 300 cycles at 0.2℃ and a good rate capability(0.2℃–5℃)equivalent to Sn.The excellent cycling performance is attributed to the novel structure of the anode as well as the strong mechanical strength of the nanowires which is directly confirmed by in-situ lithiation and bending experiments.

关键词： anode si Sn nanowire electrochemical cycling

Mechanical Properties of si and Some d-electron Metals:Force Laws, Electron Correlation and Bond-breaking

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Journal of Materials Science & Technology 1999年第4期15卷 289-295页

作者： N.H.MarChOxford University Oxford EnglandPrivate address: 6 Northcroft Road, Egham, Surrey,TW20 ODU, England Oxford University Oxford United Kingdom 6 Northcroft Road Egham Surrey TW20 ODU United Kingdom

The coordination-dependent force fleld of TersofF for covalently bonded si has been used tocalculate the cleavage force as a function of interplanar separation and hence to estimate surfaceenergies. This force field is already fitted to density functional results. The relation to bond-breaking and electron correlation will be emphasized. Finnis-sinclair-type many-body potentialshave then been used to treat some d-electron metals. In particular, results for cleavage forcein bcc Fe will be presented, and also some calculations as two perfectly planar Fe surfaces arerubbed together' at different interplanar separations. Finally, lattice dynamical models for thesteady-state propagation of a screw dislocation, and then of a crack, will be used, again within abond-breaking type of force field. For the screw dislocation propagation. a solitary wave equationis shown to follow in the 'almost continuum' limit. Energy radiated by phonons as the dislocationmoves can thereby be calculated.

关键词： Mechanical Properties of si and Some d-electron Metals Rev Electron Correlation and Bond-breaking si

Yolk-shell si/C composites with multiple si nanoparticles encapsulated into double carbon shells as lithium-ion battery anodes

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Journal of Energy Chemistry 2019年第5期28卷 124-130页

作者： Le Hu Bin Luo Chenghao Wu Pengfei Hu Lianzhou Wang Haijiao Zhang Institute of Nanochemistry and Nanobiology Shanghai UniversityShanghai 200444China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQLD 4072Australia Laboratory of Microstructure Shanghai UniversityShanghai 200444China

The conceptual design of yolk-shell structured si/C composites is considered to be an effective way to improve the recyclability and conductivity of si-based anode materials. Herein, a new type of yolk-shell structured si/C composite (denoted as TSC-PDA-B) has been intelligently designed by rational engineering and precise control. In the novel structure, the multiple si nanoparticles with small size are successfully encapsulated into the porous carbon shells with double layers benefiting from the strong etching effect of HF. The TSC-PDA-B product prepared is evaluated as anode materials for lithium-ion batteries (LIBs). The TSC-PDA-B product exhibits an excellent lithium storage performance with a high initial capacity of 2108 mAh g^-1 at a current density of 100 mA g^-1 and superior cycling performance of 1113 mAh g^-1 over 200 cycles. The enhancement of lithium storage performance may be attributed to the construction of hybrid structure including small si nanoparticles, high surface area, and double carbon shells, which can not only increase electrical conductiv让y and intimate electrical contact with si nanoparticles, but also provide built-in buffer voids for si nanoparticles to expand freely without damaging the carbon layer. The present findings can provide some scientific insights into the design and the application of advanced si-based anode materials in energy storage fields.

关键词： si/C composites Yolk-shell Multiple si nanoparticles Double carbon shells Energy storage

Study of New Way about si/si Bonding

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Rare Metals 2000年第4期19卷 290-296页

作者：刘玉岭王新张文智徐晓辉张德臣张志花 Microelectronic Research Institute Hebei University Research InstituteTianjing 300130China

A new set of technique was adopted in bonding si-si by using Ge (Ⅳ element),which is used as the substitute for the common hydrophilic method. The bond layer has no holes, and the edge bond-rate amounts to above 98%, and the bond strength is above 2156 Pa. By doping the same kind of dopant with low-resistance in Ge, the stress compensation was realized.

关键词： si Ge Bonding mechanism

High Temperature Creep behaviour of a si_3N_4 Whisker Reinforced Al-Fe-V-si Composite

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Journal of Materials Science & Technology 1998年第6期14卷 527-532页

作者： Liangming PENG Shijie ZHU Haoran CHEN and Fugang WANG(Dept. of Materials Engineering,Dalian University of Technology, Dalian 116023, China)Zongyi MA and Jing BI(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China) Dept. of Materials Engineering Dalian University of Technology Dalian 116023 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The creep behaviour of β-si3N4 whisker reinforced Al-8.5Fe-1.3V-1.7si composite has been investigated at the temperature 773 and 823 K. The results are characterized by high stress exponent and high apparent creep activation energy The creep data can be interpreted based on the incorporation of a threshold Stress and a load transfer coefficient into the power-law creep equation. A good correlation between the normalized creep rate and normalized effective stress is available which demonstrates that the creep behaviour of both the alloy and the composite is controlled by the matrix lattice self-diffusion in AI. EXamination on microstructure shows that edge dislocations exist at the interfaces between two adjacent whiskers and the intedeces emit edge dislocations in parallel paired-columns.

关键词： si Al Fe High Temperature Creep behaviour of a si3N4 Whisker Reinforced Al-Fe-V-si Composite

Growth and characterization of straight InAs/GaAs nanowire heterostructures on si substrate

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Chinese Physics B 2013年第7期22卷 377-382页

作者：颜鑫张霞李军帅吕晓龙任晓敏黄永清 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

Vertical InAs/GaAs nanowire （NW） heterostructures with a straight InAs segment have been successfully fabricated on si （111） substrate by using AlGaAs/GaAs buffer layers coupled with a composition grading InGaAs segment. Both the GaAs and InAs segments are not limited by the misfit strain induced critical diameter. The low growth rate of InAs NWs is attributed to the AlGaAs/GaAs buffer layers which dramatically decrease the adatom diffusion contribution to the InAs NW growth. The crystal structure of InAs NW can be tuned from zincblende to wurtzite by controlling its diameter as well as the length of GaAs NWs. This work helps to open up a road for the integration of high-quality III-V NW heterostructures with si.

关键词： nanowire si buffer layer adatom diffusion

A study on the interaction between ferric ion and silicic acid in hydrosphere: si-containing ferruginous deposits formed in neutral hot spring waters

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Chinese Journal Of Geochemistry 2013年第1期32卷 27-34页

作者： Gaowa Naren Akane Miyazaki Motoyuki Matsuo BAI Shuqin Kotaro Yonesu Yoshihiro Okaue Takushi Yokoyama Department of Chemistry Faculty of Science Kyushu University Department of Chemical and Biological Sciences Faculty of Science Japan Women's University Department of Chemistry Graduate School of Arts and Sciences University of Tokyo College of Environment and Resources Inner Mongolia University Department of Earth Resources Engineering Faculty of Engineering Kyushu University

Five ferruginous deposit samples formed from neutral hot springs were analyzed to determine whether they consisted of a mixture of silica, hydrous iron oxide or iron silicate by differential thermal analysis (DTA), infrared (IR) spectroscopy, powder X-ray diffraction (XRD), and 57Fe Mssbauer spectroscopy. The si/Fe atomic ratios of the deposits ranged from 0.25 to 0.45, and were smaller than those of hisingerite (12), but apparently close to those of siliceous ferrihydrite (0.250.5). si was confirmed to be present as monomeric or oligomeric silicate from the si-O stretching vibration frequencies on the IR spectra. Judging from the results of DTA, which minerals starting to produce after heating, and a relationship between si-O stretching vibration frequency and si/Fe atomic ratio proposed by Henmi et al. (1981), all the deposits in this study were concluded to be mixtures of various siliceous ferri-hydrites with low and high si/Fe atomic ratios. Moreover, by comparing the chemical properties of hot spring waters, the formation conditions of siliceous ferrihydrite were also discussed.

关键词：温泉水硅酸盐三价铁离子 si 相互作用中性铁质伸缩振动频率

Effects of Cr interlayer on mechanical and tribological properties of Cr-Al-si-N nanocomposite coating

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 62-67页

作者： Young Su HONG Se Hun KWON Tiegang WANG Doo-In KIM Jihwan CHOI Kwang Ho KIM School of Materials Science and Engineering Pusan National University National Core Research Center for Hybrid Materials Solution Pusan National University

Cr-Al-si-N coatings were deposited on SUS 304 substrate by a hybrid coating system. A Cr interlayer was introduced between Cr-Al-si-N coating and SUS 304 substrate to improve the coating adherence. The effects of Cr interlayer on the microhardness, adhesion, and tribological behavior of Cr-Al-si-N coatings were systematically investigated. The results indicate that the microhardness of the Cr-Al-si-N coatings gradually deceases with increasing thickness of Cr interlayers. The adhesion between Cr-Al-si-N and SUS 304 substrate is improved by addition of the Cr interlayers. A peak critical load of ~50 N is observed for the coating containing Cr interlayer of 60 nm as compared ~ 20 N for the coating without Cr interlayer. The thicker Cr interlayers result in reduced critical load values. Moreover, the wear resistance of the Cr-Al-si-N coatings is greatly enhanced by introducing the Cr interlayer with thickness of 60 nm in spite of the decreased microhardness. The friction coefficient of the coating system is also moderately reduced.

关键词：夹层厚度铬涂层复合涂层纳米晶摩擦学性能 si 中间层涂料机械