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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 227-234页

作者： Yang Wu Yun-Chang Xin Xiang-Sheng Xia Bo Feng Yan-Bin Wang Zu-De Zhao Southwest Technology and Engineering Research Institute International Joint Laboratory for Light Alloys College of Materials Science and Engineering Chongqing University Guangdong Institute of Materials and Processing Guangdong Academy of Sciences

Mg AZ31/A1 7050 laminate was fabricated by co-extrusion directly from the as-cast Mg AZ31 and Al 7050 billets. The influence of annealing temperature and annealing time on microstructure and mechanical behavior of the extruded Mg/Al laminate was systematically studied. Results show that annealing treatments at 250 ℃ for 3 h or at 350 ℃ for 3 h do not result in an obvious grain coarsening of Mg layer and cannot remove the heterogeneous structure. Annealing does not vary texture in the Mg layer, a large fraction of //ND and a small fraction of //TD, but the intensity of component //ND weakens to some extent. Lamellar microstructure in the A1 layer remains after annealing at250 ℃ for 3 h or at 350 ℃ for 3 h. High fractions of the texture components S and cube exist in the extruded sample, and annealing treatment hardly changes their fractions. Post-annealing treatment will largely reduce yield strength of extruded plate and increase plasticity slightly. The yield strength drops from 302 MPa to 206 MPa after annealing at 250 ℃ for 3 h and to 141 MPa after annealing at 350 ℃ for 3 h. The elongation to fracture increases from 1.5% to 5.4% after annealing at 250 ℃ for 3 h and to 4.8% at 350 ℃ for 3 h. The corresponding mechanism was discussed.

关键词： laminate composite Annealing Microstructure Texture Mechanical property

Rational design of a laminate-structured flexible sensor for human dynamic plantar pressure monitoring

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Microsystems & Nanoengineering 2024年第4期10卷 201-210页

作者： Zuoping Xiong Yuanyuan Bai Lianhui Li Zhen Zhou Tie Li Ting Zhang School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefeiAnhui 230026P.R.China i-lab Nano-X Vacuum Interconnected WorkstationSuzhou Institute of Nano-Tech&Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)SuzhouJiangsu 215123P.R.China Suzhou Leanstar Electronic Technology Co. LtdSuzhouJiangsu 215000P.R.China

Flexible sensors are essential components in emerging fields such as epidermal electronics,biomedicine,and humancomputer interactions,and creating high-performance sensors through simple structural design for practical applications is increasingly ***,challenges still exist in establishing efficient models of flexible piezoresistive pressure sensors to predict the design required for achieving target *** work establishes a theoretical model of a flexible pressure sensor with a simple laminated and enclosed *** the modeling,the electrical constriction effect is innovatively introduced to explain the sensitization mechanism of the laminated structure to a broad range of pressures and to predict the sensor *** experimental results confirmed the effectiveness of the theoretical *** sensor exhibited excellent stability for up to three million cycles and superior durability when exposed to salt solution owing to its simple laminated and enclosed structural ***,a wearable sensing system for real-time collection and analysis of plantar pressure is constructed for exercise and rehabilitation monitoring *** work aims to provide theoretical guidance for the rapid design and construction of flexible pressure sensors with target performance for practical applications.

关键词： Rational laminated laminate

Reinforcing effect of laminate structure on the fracture toughness of Al3Ti intermetallic

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 678-686页

作者： Yang Cao Dan-dan Zhang Pei-jun Zhou Kun Liu Wu-yi Ming Jun Ma Mechanical and Electrical Engineering Institute Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory of Superlight Materials&Surface Technology Ministry of Education Harbin Engineering UniversityHarbin 150001China

Metal/intermetallic laminate composites can improve the mechanical properties of intermetallic materials using metal layers. In recent years, titanium aluminide intermetallics have received increasing attention due to their excellent performance properties, such as high melting point, high specific strength and stiffness, and good corrosion resistance. However, the low fracture toughness of Al3Ti alloys at room temperature has greatly limited their application, and fiber or particle reinforcement has not shown a significant toughening effect. Research into the reinforcing effects of the interface and near-interface zone on the fracture behavior of Al3Ti is lacking. Ti/Al3Ti metal/intermetallic laminate composite was synthesized from titanium and aluminum foils using vacuum hot-pressed sintering technology. The microstructure of the prepared material was analyzed by scanning electron microscope and electron backscattered diffraction. Results illustrate that both Ti and Al3Ti were single-phase and there was a noticeable stress concentration on the interface. To obtain indentation and cracks, loads were applied to different locations of the composite by a microhardness tester. The growth path of the cracks was then observed under microscope, showing that crack propagation was prevented by the interface between the Ti and Al3Ti layers, and the cracks that propagated parallel to the laminate shifted to the interface. Fracture toughness of the different areas, including Al3Ti layers, interface, and near-interface zone, were measured by the indentation fracture method. The fracture toughness at and near the interface was 1.7 and 2 times that of the Al3Ti layers, respectively. Results indicate that crack blunting and crack front convolution by the laminate structure was primarily responsible for increased toughness.

关键词： interface titanium tri-aluminide intermetallic titanium/titanium tri-aluminide metal/intermetallic laminate composite toughening effect indentation fracture method

Magnetic-Field-Induced Stress-Birefringence in laminate Composites of Terfenol-D and Polycarbonate

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Chinese Physics Letters 2013年第7期30卷 233-235页

作者： LUO Xiao-Bin WU Dong ZHANG Ning Magneto-electronic Lab and Key Lab of Optical-electronic Techniques of Jiangsu ProvinceNanjing Normal UniversityNanjing 210046

The laminate composites that can show the magneto-birefringence effect are suggested and fabricated by the product of magnetostriction and *** a magnetic field no stronger than 1900 Oe,a phase difference of~3.3π is observed for a trilayer composite Tb_(1-x)Dy_(x)Fe_(2-y)/polycarbonate/Tb_(1-x)Dy_(x)Fe_(2-y) with a polycarbonate layer at a size of 5×2.75×20 mm^(3) at room temperature,resulting in a half-wave magnetic field of no greater than 270 Oe.

关键词： laminate composites composite

Internal friction peak and damping mechanism in high damping aluminium alloy laminate

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中国有色金属学会会刊：英文版 2001年第1期11卷 123-127页

作者：张迎元中国船舶重工集团河南洛阳 471039

A new aluminium alloy laminate characterized by high damping, corrosion resistance and weldablity was developed. The laminate designed for required aforesaid functions was actually a composite material, which was made of two anti corrosive layers (Al), two damping layers (ZnAl alloy) and one reinforcing layer (AlMg alloy) by hot rolling. The damping characteristics were studied and it was found that there was an internal friction peak at about 50 ℃ on internal fraction vs temperature curve for the laminate. For this reason, the activation energy of the peak was calculated. The origin and damping mechanism for this peak was researched by means of SEM, TEM, X ray and DSC. It is considered that the peak is caused by the interaction between dislocations and point defects in damping layers (AlZn alloy). i.e. by the movement of dislocations dragging point defects under the action of thermal activation. The laminate is remained at room temperature for a long time, it will weaken or even disappear with the restoration of the crystal microstructure and the reduction of the dislocation density in the ZnAl alloy layers. The mechanism of the peak is in conformity with that of the dislocation induced damping. [

关键词： aluminium alloy laminate composite damping internal friction

Mechanical properties and damping characteristics of laminate

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中国有色金属学会会刊：英文版 1994年第3期4卷 102-105页

作者： Luo, Binghui Zhou, Shanchu Song, Youreng(Department of Materials Science and Engineering ,Celtral South University of Technology , Changsha 410083)

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＤＡＭＰＩＮＧＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＬＡＭＩＮＡＴＥＬｕｏ，Ｂｉｎｇｈｕｉ；Ｚｈｏｕ，Ｓｈａｎｃｈｕ；Ｓｏｎｇ，Ｙｏｕｒｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔ... 详细信息

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＤＡＭＰＩＮＧＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＬＡＭＩＮＡＴＥＬｕｏ，Ｂｉｎｇｈｕｉ；Ｚｈｏｕ，Ｓｈａｎｃｈｕ；Ｓｏｎｇ，Ｙｏｕｒｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥ...

关键词： laminate internal friction relaxation process viscous motion

ANALYTICAL－GENERALIZED VARIATIONAL METHOD ABOUT SOLUTION OF SIF AND CONSERVATIVE INTEGRAL FOR DELAMINATlONS OF laminate BEAM

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Chinese Journal of Aeronautics 1994年第1期7卷 23-31页

作者： Zhang Xing Meng Qingchun(Faculty 508,Beijing University of Aeronautics and Astronautics, Beijing,China,100083)

AbstractIn this paper,first of all,the eigen expansions of stress and displacement fields satis-fying all governing equations, boundary conditions along crack surfaces and conditions ofcontinuity along hgament of two dissimilar media are ***, the formula of con-servative integral J1 for the above media with interface crack is established and applied tothe case of detamination of composite laminate beam stacked ***,the coefficients of the above expansions are determined by generalized variational method,then the values of J1 can be *** stress intensity factor Kn found directly fromthe leading term of the above expansions agrees with that indirectly from J1 satisfactorily,the convergency of results with increase of number of terms in the above expansions is verynice and values of J1 obtained from different paths of integration keep constantaccurately.

关键词： BEAM ANALYTICAL AND ABOUT CONSERVATIVE DELAMINATlONS FOR GENERALIZED INTEGRAL laminate

laminate Tailoring of Composite Tubular Structures to Improve Crashworthiness Design at Off-Axis Loading

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Open Journal of Composite Materials 2018年第3期8卷 84-109页

作者： A. Rabiee H. Ghasemnejad Centre for Structures Assembly and Intelligent Automation Cranfield University Cranfield UK

This paper presents experimental and numerical investigation on the parameters effecting energy absorption capability of composite tubular structures at oblique loading to improve crashworthiness performance. Various inclined angles of 5°, 10°, 20° and 30° were selected for the study of off-axis loading. The results indicate that by increasing the lateral inclination angle the mean crushing force and also energy absorption capability of all tested sections decreased. From design perspective, it is necessary to investigate the parameters effecting this phenomenon. The off-axis loading effect that causes significant reduction in energy absorption was investigated and the effected parameters were improved to increase energy absorption capability. To establish this study, 10° off-axis loading was chosen to illustrate the obtained improvement in energy absorption capability. Five cases were studied with combinations of ply-orientation and flat trimming with 45° chamfer. This method was applied to the integrated 10° off-axis loading and the final results showed significant improvement in energy absorption capability of composite absorbers. Finite element model (FEM) was developed to simulate the crushing process of axial and off-axis composite section in LS-DYNA and the results were in good agreement with the experimental data.

关键词： Crashworthiness Composites laminate Tailoring Off-Axis Oblique

Interval Analysis Method on the Buckling of Composite laminate

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Chinese Journal of Aeronautics 2005年第3期18卷 218-222页

作者：邱志平李飞杨嘉陵 Institute of Solid Mechanics Beijng University of Aeronautics and Astronautics Beijng 100083 China

A method named interval analysis method, which solves the buckling load of composite laminate with uncertainties, is presented. Based on interval mathematics and Taylor series expansion, the interval analysis method is used to deal with uncertainties. Not necessarily knowing the probabilistic statistics characteristics of the uncertain variables, only little information on physical properties of material is needed in the interval analysis method, that is, the upper bound and lower bound of the uncertain variable. So the interval of response of the structure can be gotten through less computational efforts. The interval analysis method is efficient under the condition that probability approach cannot work well because of small samples and deficient statistics characteristics. For buckling load of a special cross-ply laminates and antisymmetric angle-ply laminates with all edges simply supported, calculations and comparisons between interval analysis method and probability method are performed.

关键词： laminate buckling load uncertain parameter interval analysis probabilistic statistics method

Interlaminar Fracture Toughness of Epoxy Glass Fiber Fly Ash laminate Composite

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Materials Sciences and Applications 2014年第4期5卷 231-244页

作者： Ajit Bhandakkar Niraj Kumar R. C. Prasad Shankar M. L. Sastry Department of Metallurgical Engineering and Materials Science Indian Institute of Technology Bombay Mumbai India Mechanical Aerospace and Structural Engineering Washington University in St. Louis Saint Louis USA

Epoxy glass fiber laminate composite (PMCs) are finding ever increasing applications in aerospace and automobile industries due to its high strength to weight ratio and resistance to aqueous environment. Additions of particulate reinforcements in the polymer matrix are reported to improve the Interlaminar Shear Strength and Interlaminar Fracture Toughness of the composites. In the present investigation, epoxy glass fiber laminate composites were processed using hand layup and vacuum bagging technique. The particulate reinforcement precipitator fly ash (25 - 45 μm) was added in the epoxy matrix by mechanical mixing up to 10 wt%. The effects of fly ash reinforcement on the mechanical properties and Interlaminar Fracture Toughness were studied before and after exposure to aqueous fog in a salt fog chamber at 45°C. In unexposed condition Mode I interlaminar fracture toughness of epoxy glass fiber laminate composite improved by the addition of fly ash reinforcement 10% (By weight) by 49.43% and when it was subjected to aqueous fog for 10 days the interlaminar fracture toughness improved 58.42%. Exposure to aqueous fog for 10 days causes plasticization of resin matrix and weakening of fiber/matrix interface results in improvement in interlaminar fracture toughness. The fracture surfaces were analyzed using scanning electron microscopy.

关键词： Interlaminar Fracture Toughness Epoxy Glass Fiber laminate Composite Fly Ash