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Experimental and Numerical Investigation on Impact Performance of Carbon Reinforced Aluminum Laminates

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Journal of Materials Science & Technology 2010年第4期26卷 327-332页

作者： S.h. song Y.S. Byun T.W. Ku W.J. song J. Kim B.S. Kang National Core Research Center Pusan National University Busan 609-735 Korea Dept. of Aerospace Engineering Pusan National University Busan 609-735 Korea Industrial Liaison Innovation Cluster Pusan National University Busan 609-735 Korea

It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, ABAQUS. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.

关键词： Fiber metal laminates (FML) Carbon reinforced aluminum laminates (CARAL) Numerical simulation Impact performance

Plastic Effect on the Sliding Inception Bet ween a Cylinder and a Rigid Flat

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Acta Mechanica Solida Sinica 2019年第1期32卷 1-16页

作者： S.Zhang J.huan h.song X.Liu Y.G.Wei LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China Department of Mechanical Engineering Johns Hopkins UniversityBaltimoreMD 21218USA College of Engineering Peking UniversityBeijing 100871China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

The effec ts of mat erial plasticity and local slip on the sliding inception of asperity are studied in the present ***,a semi-analytical solution is derived under the full-stick condition to analyze the effect of material plasticity on sliding ***,a friction model with contact stiffness criterion is proposed to study the cases from partial-slip condition to full-stick *** element simulations with the provided model are used to present the friction *** friction coefficient of full-s tick interface converges at a st able value,approxima tely *** saturation appears as the normalized contact interference u*is larger than 3.A transition mechanism from slip-dominated to yield-dominated takes place in the sliding *** simulation results are compared with the semi-analytical solution.

关键词： Mat erial yielding Local slip Contact stiffness criterion Finite element simulation

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多模式网络化控制系统稳定性分析

控制理论与应用 2006年第5期23卷 749-755页

作者：郑刚谭民 song Y h 中国科学院软件研究所通用软件实验室北京100080 中国科学院自动化研究所北京100080 布鲁内尔大学电子与计算机工程系英国伦敦

网络传输引起的时滞在网络化控制系统中经常出现．针对存在多个运动模式的网络化控制系统,建立了时滞混杂自动机模型,分析了系统平衡点的稳定性,给出了平衡点保持稳定的充分条件在于构造的与离散状态相关的Lyapunov泛函在离散状态的切... 详细信息

网络传输引起的时滞在网络化控制系统中经常出现．针对存在多个运动模式的网络化控制系统,建立了时滞混杂自动机模型,分析了系统平衡点的稳定性,给出了平衡点保持稳定的充分条件在于构造的与离散状态相关的Lyapunov泛函在离散状态的切换时刻是非增的．当时滞混杂自动机中连续性子系统为线性时不变时滞系统时,可以利用线性矩阵不等式方法来寻找系统的公共Lyapunov泛函,并求解使系统平衡点保持稳定的时滞上界．最后,给出了一个例子说明了分析结果．

关键词：网络控制混杂系统稳定性时滞系统线性矩阵不等式

GRAIN-BOUNDARY PRECIPITATION UNDER IRRADIATION IN DILUTE BINARY ALLOYS

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 365-374页

作者： S.h.song Z.X.Yuan J.Liu R.G.Faulkner SchoolofMaterialsandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China InstituteofPolymerTechnologyandMaterialsEngineering LoughboroughUniversityLoughboroughLe-icestershireLE113TUUK

Irradiation-induced grain boundary segregation of solute atoms frequently bring about grain boundary precipitation of a second phase because of its making the solubility limit of the solute surpassed at grain boundaries. Until now the kinetic models for irradiation-induced grain boundary precipitation have been sparse. For this reason, we have theoretically treated grain boundary precipitation under irradiation in dilute binary alloys. Predictions of γ' -Ni3Si precipitation at grain boundaries are made for a dilute Ni-Si alloy subjected to irradiation. It is demonstrated that grain boundary silicon segregation under irradiation may lead to grain boundary γ'-Ni3Si precipitation over a certain temperature range.

关键词： segregation precipitation grain boundary irradiation

heavy Metals in Brown Rice(Oryza sativa L.) and Soil After Long-Term Irrigation of Wastewater Discharged from Domestic Sewage Treatment Plants

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Pedosphere 2011年第5期21卷 621-627页

作者： B.Y.ChUNG C.h.song B.J.PARK J.Y.ChO Advanced Radiation Technology Institute Korea Atomic Energy Research Institute(KAERI) Korea Testing & Research Institute(KTR) Department of horticultural Science Chungbuk National University Department of Bio-environmental Chemistry Chonbuk National University

A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals(Pb,Cd,Cu,and Zn) into brown rice(Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time(3 years).The range of Pb,Cd,Cu,and Zn was 5.10 ± 0.01,0.105 ± 0.017,5.76 ± 0.42,and 23.56 ± 1.40 mg kg-1,respectively in the domestic wastewater-irrigated soil,and 0.370 ± 0.006,0.011 ± 0.001,0.340 ± 0.04,and 2.05 ± 0.18 mg kg-1,respectively,in the domestic wastewater-irrigated brown *** results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb,Cd,Cu,and Zn in soil and brown rice(P he concentrations of heavy metals in brown rice were lower than the recommended tolerable levels proposed by the Joint FAO/WhO Expert Committee on Food ***,the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.

关键词： accumulation domestic wastewater ground water irrigation P2O5 total N

NONLOCAL ThEORY STUDY ON FRACTURE TOUGhNESS OF CERAMIC MATERIALS

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Acta Metallurgica Sinica(English Letters) 1996年第4期9卷 256-262页

作者： X.h.song(Centre for Materials Research and Analysis,Wuhan University of Technology,Wuhan 430070,China )

The theoretical calculation formulas for the plane strain fracture toughness of mode Ⅰand Ⅱcracks of ceramic materials are deduced in this paper by using the nonlocal elasticity theory and maximum tensile stress criterion The deduced formulas, which are independent of crack geometry,bear a relation to material *** is shown through experiment that the theoretical value of fracture toughness is the lower limit of testing value. The theoretical calculation formulas for fracture toughness relate the macro-mechanical performance of materials with the micro-structural parameters and,therefore, are beneficial to fully understanding the physical mechanism of material rupture.

关键词： nonlocal elasticity theory fracture toughness,ceramic material

AB INITIO CALCULATION OF ThE ELASTIC AND OPTICAL PROPERTIES OF Al3Sc COMPOUND

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Acta Metallurgica Sinica(English Letters) 2007年第6期20卷 425-428页

作者： M. song D.h. Xiao State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083 China

The ab initio method has been performed to explore the elastic and optical properties of Al3Sc compound, based on a plane wave pseudopotential method. It can be seen that the calculated equilibrium lattice parameter and elastic constants are in reasonable agreement with the previous experimental data. The elastic constants satisfy the requirement for mechanical stability in the cubic structure of the Al3Sc compound. The optical property calculations show that a strong absorptive peak exists from O-15eV and a relative small absorptive peak exists around 30eV. The form is caused by the optical transitions between high s, p, and d bands, and the latter results from the optical transitions from high s, p, and d bands to the low 2p band.

关键词： intermetallic compound Al3Sc, elastic property optical property ab initio calculation

PhOSPhORUS GRAIN BOUNDARY SEGREGATION IN A P-DOPED 2.25Cr1Mo STEEL

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 639-644页

作者： D.D.Shen Z.X.Yuan J.Liu S.h.song L.Q.Wen ThehubeiProvinceKeyLaboratoryofCeramicsandRefractories WuhanUniversityofScienceandTechnologyWuhan430081China SchoolofMaterialsScienceandEngineering NanjingUniversityofAeronauticsandAstronauticsNanjing210016China

Grain boundary segregation of phosphorus during tempering at 540℃ after quenching from 980℃ is examined for a P-doped 2.25Cr1Mo steel by means of Auger electron spectroscopy. The solute-boundary binding energy and the diffusion coefficient for phosphorus are determined by virtue of the measured segregation kinetics along with the equilibrium segregation theory. The obtained values of the above parameters are discussed with comparison to those found in the literature for low-alloy steels.

关键词： segregation grain boundary low-alloy steel phosphorus

Magnetic/Magnetostrictive Properties Together with Resistivity and Corrosion Behaviors of CoFe_2 and Its Composite with CoFe_2N

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Journal of Materials Science & Technology 2017年第7期33卷 744-750页

作者： B.Q.Geng Y.Q.Ma M.Wang Z.L.Ding W.h.song B.C.Zhao Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

The CoFe_2alloy（CF） was prepared by reducing CoFe_2O_4 in the h_2 ambient. Subsequently the CF sample was nitrided in the Nh_3 atmosphere to produce the composite of CoFe_2N and CoFe_2. The magnetostriction, thermal expansion, resistivity and corrosion resistance of CF sample and the nitrided sample（CFN）at 1000？C were investigated. The saturation magnetostriction coefficiency λ_s and thermal expansion coefficient ？ at 300 K for the nitrided CFN were 50 ppm and 10 ppm/K, respectively, approximately equal to those for the CF sample. however, compared with CF, CFN presents a decrease in temperature coefficient R_λ（300 K） of magnetostriction by 11%. The smaller resistivity and improved corrosion resistance in the h_2SO_4 solution may expand the applications of the CoFe_2 in the fields needing lower resistivity or in the acidic environment.

关键词： CoFe alloy CoFe_2N alloy Magnetostriction Resistivity Corrosion resistance