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MICROSTRUCTURE AND MACROSEGREGATION OF Al-7%Si ALLOY SOLIDIFIED UNDER COMPLEX EFFECTS OF ELECTROMAGNETIC AND CENTRIFUGAL FORCES

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Acta Metallurgica Sinica(English Letters) 1997年第2期10卷 105-114页

作者： Y.F. zhu W.q. zhang Y.S. Yang q.M. Liu and z.q. Hu (State Key Lab. of RSA, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015,Chilla) Inst of Metal Research Chinese Acad of Sciences Shenyang China

Macrosegregations and microstructures of Al-7%Si alloy solidified under complex of fects of magnetic field and centrifugal forces are studied by means of a set of selfdesigned electromagnetic centrifugal casting (EMCC) device. It is shown that electromagnetic field (EMF) has an important effect on the macrosegregation of centrifugal casting specimen of Al-7%Si alloy in two respects: one is that there exists always a kind of convection in the liquid in front of the S/L interface caused by effect ofthe electromagnetic force; the other is that different atomic clusters of solidparticles with different physical characteristics are subjected to quite different electromagnetic (Lorentz) force. Therefore, their movements get changed. In addition, the formation process of a complex band structure consisting of primary α-Al dendrites and (α-Al+β-Si) eutectics in hypoeutectic Al-Si alloys during EMCC and the effect of EMF are discussed.

关键词： electromagnetic field (EMF) centrifugal force Al-7%Si alloy macrosegregation solidification microstructure convection

Lithium niobate electro-optical modulator based on ion-cut wafer scale heterogeneous bonding on patterned SOI wafers

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Photonics Research 2025年第1期13卷 106-112页

作者： zHUOYUN LI YANG CHEN SHUXIAO WANG FAN XU qIANG XU JIANMIN zHANG qIANNAN zHU WENCHENG YUE XIN ou YAN CAI MINGBIN YU State Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences School of Microelectronics Shanghai University Shanghai IndustrialμTechnology Research Institute Shanghai Mingkun Semiconductor Co. Ltd.

This paper presents the design, fabrication, and characterization of a high-performance heterogeneous silicon on insulator (SOI)/thin film lithium niobate (TFLN) electro-optical modulator based on wafer-scale direct bonding followed by ion-cut technology. The SOI wafer has been processed by an 8 inch standard fabrication line and cut into 6 inch for direct bonding with TFLN. The hybrid SOI/LN electro-optical modulator operated at the wavelength of 1.55μm is composed of couplers on the Si layer and a Mach–zehnder interferometer (MzI) structure on the LN layer. The fabricated device exhibits a stable value of the product of half-wave voltage and length (VπL) of around 2.9 V·cm. It shows a good low-frequency electro-optic response flatness and supports 96 Gbit/s data transmission for the NRz format and 192 Gbit/s data transmission for the PAM-4 format.

关键词： Complementary metal oxide semiconductors Effective refractive index Lithium niobate Material properties Silicon modulators Thin films

STRUCTURE OF Al-Cu EUTECTIC ALLOY SOLIDIFIED IN COMPLEX FIELD OF CENTRIFUGAL AND ELECTROMAGNETIC FORCES

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Acta Metallurgica Sinica(English Letters) 1997年第2期10卷 120-126页

作者： W.q. zhang Y.F. zhu Y.S. Yang and z.q. Hu (State Key Lab. of RSA, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015,China) Inst of Metal Research Chinese Acad of Sciences Shenyang China

The effects of magnetic field on macro and microstructure of Al-CuAl2 eutectic alloy produced by electromagnetic centrifugal casting have been erperimentally investigated in the present paper. Electromagnetic stirring can lead to columnar formation in the cuter region and equiaxed in the inner, and otherwise cause the lamellae coarsened and the microstructure morphology to change from lamella to rod and then to block,if the electromagnetic stirring is intensified.

关键词： electromagnetic stirring centrifgal force Al-Cu eutectic alloy

Influence of Re on the Properties of a NiCoCrAlY Coating Alloy

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Journal of Materials Science & Technology 2011年第5期27卷 408-414页

作者： J.J. Liang H. We Y.L. zhu X.F. Sun z.q. Hu M.S. Dargusch X.D. Yao Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China School of Materials & Mining Engineering The University of Queensland QLD 4072 Australia

MCrAIY can serve as stand-alone overlay coatings or bond coats in thermal barrier coating systems, and its properties play a vital role in determining the performance of these coating systems. In order to further understand the behavior of MCrAIY coatings, several NiCoCrAIY model alloys with different levels of Re （0.3 wt%, O wt%, and 9 wt%） were investigated. Microstructural observation showed the addition of Re promoted the precipitation of Cr-rich phases, such as α-Cr and σ. The presence of α-Cr lowered the coefficient of thermal expansion （CTE） of the coating alloys, which could reduce the CTE mismatch at the scale-metal interface. The solid solution strengthening effect of Re is responsible for an increase in Rockwell hardness of the coating alloys. But the isothermal oxidation resistance at 1100℃ was deteriorated due to the precipitation of brittle α-Cr phase, a phase of inferior oxidation resistance compared with β-NiAI and γ-Ni.

关键词： NiCoCrAIY Phase constitution Oxidation Thermal expansion behavior Hardness

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Mg-Li ALLOY WITH Ca ADDITION

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 355-361页

作者： H.B. Li G. C. Yao z.q. Guo Y.H. Liu H.J. Yu H.B. Ji School of Materials ＆ Metallurgy Northeastern University Shenyang 110004 China

Mg-9wt%Li-2wt%zn alloy was prepared and studied in this article. The addition of Ca to the alloy from 0.1wt% to 1wt% can refine the α-Mg and the best effect of refinement occurs when Ca content is 0.4wt%-0.5wt%. The billets can be rolled to thin sheets at room temperature, from which it is obvious that the addition of Ca improves alloys ormalin. while it decreases with the excess addition of Ca. The results also show that the ultimate tensile strength （UTS） and yield strength （YS） of the alloy with lwt% Ca may rise by 28% and 25%, respectively, however, the elongation decreases. It is clarified that the adsorption of proper Ca on the grain boundaries refines α-Mg and improves the tensile properties, but the presence of excess Ca and stable Ca2Mg6zn3phase worsens the elongation.

关键词： calcium Mg-Li-zn alloy cold rolling microstructure tensile property

DYNAMIC STRAIN AGING BEHAVIOR OF K40S ALLOY

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 473-477页

作者： F.M. Yang, X.F. Sun, H.R. Guan and z.q. HuInstitute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The dynamic strain aging behavior during tensile tests of K40S alloy has been investigated in the temperature range of 25-1100℃ with the strain rate range from 10-4 to 10-3s-1. The results show that four different types of serration, identified as A, B, C and E type serration were observed in the temperature range of 300-600℃. The strain exponents for onset of the serrated flow were calculated as 1.21, 2.19 and 1.61, and the activation energies as 121, 40 and 67kJ/mol for E, B and C type serration respectively. The main mechanism for dynamic strain aging discussed in light of the strain exponent and the activation energy.

关键词： dynamic strain aging serrated flow strain exponent activation energy

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.q.Ye z.q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Understanding the Influence of inerter in vibration systems

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Understanding the Influence of inerter in vibration systems

When joggers meet robots:the past,present,and future of research on humanoid robots

第三届海峡两岸动力学、振动与控制学术会议

作者： Michael z.q. Chen 黄立锡 Lab of Aerodynamics and Acoustics Dept of Mechanical Engineering and HKU Zhejiang Institute of Research and Innovation The University of Hong Kong 香港大学机械工程系

Inerter is a recently proposed concept and a device with the property that the applied force at its two terminals is proportional to the relative acceleration between them. As a new passive mechanical element, the performance benefits of using inerters in various mechanical systems have been well demonstrated. This work investigates the influence of inerter on the natural frequencies of vibration systems. By

关键词： Understanding the Influence of inerter in vibration systems

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Bio-Design and Manufacturing 2019年第2期2卷 108-118页

作者： George H.z.Liu Michael z.q.Chen Yonghua Chen Department of Mechanical Engineering The University of Hong KongPokfulamHong KongPeople’s Republic of China School of Automation Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China

Spawned by fast-paced progress in new materials and integrate circuit technology,the past two decades have witnessed tremendous development of humanoid robots for both scientific and commercial purposes,*** response and daily life *** the root of this trend are the increasing research interests and cooperation opportunities across different laboratories and *** application-driven requirements of high effectiveness and reliability of humanoid robots led intensive research and development in humanoid locomotion and control *** spite of the progress in the area,challenges such as unnatural locomotion control,inefficient multi-motion planning,and relatively slow disturbances recovery set further requirements for the next generation of humanoid ***,the purpose of this work is to review the current development of highly representative bipedal humanoid robots and discuss the potential to move the ideas and models forward from laboratory settings into the real *** this end,we also review the current clinical understanding of the walking and running dynamics to make the robot more human-like.

关键词： Humanoid robot Walking dynamics Dynamic control Bio-inspired gait Robot efficiency Shock absorption