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A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze Yu Jie Yu Yulan Lu Bo Xie Jian Chen Deyong Chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

Experimental,Numerical,and Analytical Studies on the bending of Mechanically Lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN Lin ZHOU Jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

Effect of equal channel angular extrusion on Al-6063 bending fatigue characteristics

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 395-404页

作者： J.Nemati G.H.Majzoobi S.Sulaiman B.T.H.T.Baharudin M.A.Azmah Hanim Department of Mechanical and Manufacturing Engineering University Putra Malaysia Engineering Faculty Bu-Ali Sina University School of Mechanics Islamic Azad UniversityTakestan Branch

The purpose of this investigation was to refine the grains of annealed 6063 aluminum alloy and to improve its yield stress and ul- timate strength. This was accomplished via the equal channel angular extrusion （ECAE） process at a temperature of 200℃ using route A, with a constant ram speed of 30 mm/min through a die angle of 90° between the die channels for as many as 6 passes. The experiments were conducted on an Avery universal testing machine. The results showed that the grain diameter decreased from 45 μm to 2.8 μm after 6 extru- sion passes. The results also indicated that the major improvement in fatigue resistance occurred after the first pass. The subsequent passes improved the fatigue life but at a considerably lower rate. A maximum increase of 1100% in the case of low applied stresses and an ap- proximately 2200% increase in fatigue resistance in the case of high applied stresses were observed after 5 passes. The improvement of fa- tigue resistance is presumed to be due to （1） a reduction in the size and the number of Si crystals with increasing number of ECAE passes, （2） the aggregation of Cu during the ECAE process, （3） the formation and growth of CuA12 grains, and （4） grain refinement of the A1--6063 alloy during the ECAE process.

关键词： aluminum alloys equal channel angular pressing bending fatigue life grain size microstructure

Torque and bending moment acting on a flexible shaft agitated by disk turbines in a gas–liquid stirred vessel

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Chinese Journal of Chemical Engineering 2019年第4期27卷 781-793页

作者： Yangyang Liang Zhengming Gao Dai'en Shi Haotian Li Yuyun Bao Ziqi Cai State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Mechanical Engineering School Yancheng Institute of Technology Yancheng 224051 China

The torque and bending moment acting on a flexible overhung shaft in a gas–liquid stirred vessel agitated by a Rushton turbine and three different curved-blade disk turbines(half circular blades disk turbine, half elliptical blades disk turbine, and parabolic blades disk turbine) were experimentally measured by a customized moment sensor. The results show that the amplitude distribution of torque can be fitted by a symmetric bimodal distribution for disk turbines, and generally the distribution is more dispersive as the blade curvature or the gas flow rate increases. The amplitude distribution of shaft bending moment can be fitted by an asymmetric Weibull distribution for disk turbines. The relative shaft bending moment manifests a "rising-falling-rising" trend over the gas flow number, which is a corporate contribution of the unstable gas–liquid flow around the impeller, the gas cavities behind the blades, and the direct impact of gas on the impeller. And the "falling" stage is greater and lasts wider over the gas flow number for Rushton turbine than for the curved-blade disk turbines.

关键词： Shaft bending moment Torque Disk turbines Gas–liquid flow Fluid structure interaction

Finite element modelling and experimental investigation of the impact of filling different materials in copper tubes during 3D free bending process

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Chinese Journal of Aeronautics 2020年第2期33卷 721-729页

作者： Xunzhong GUO Xuan CHENG Yong XU Jie TAO Ali ABD EL-ATY Hai LIU College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100China Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211100China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Precision Manufacturing Engineering Suzhou Vocational Institute of Industrial TechnologySuzhou 215104China

3D free bending process,an advanced metal forming technology,has attracted much attention due to its unique geometrical flexibility and *** tubes with materials may effectively reduce the distortion in the cross-section area and restrain wrinkling and collapse of tube *** the present study,the impacts of filling different materials on the copper tubes during 3D free bending process were *** have found that copper tubes filled with low melting point alloys could induce the most uniform stress distribution,which result in better formability and moderate thickness changing rates when compared to SS304 steel balls and PU *** lowest ellipticity reached to 1.467%.

关键词： 3D free bending Ellipticity Filling bending Finite element modelling Force model Thickness

Contact force and mechanical loss of multistage cable under tension and bending

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Acta Mechanica Sinica 2016年第5期32卷 891-904页

作者： Yanyun Ru Huadong Yong Youhe Zhou Key Laboratory of Mechanics on Disaster and Environment in Western China Ministry of Education of China Department of Mechanics and Engineering Sciences College of Civil Engineering and Mechanics Lanzhou University

A theoretical model for calculating the stress and strain states of cabling structures with different loadings has been developed in this paper. We solve the problem for the first- and second-stage cable with tensile or bending strain. The contact and friction forces between the strands are presented by two-dimensional contact model. Several theoretical models have been proposed to verify the results when the triplet subjected to the tensile strain, including contact force, contact stresses, and mechanical loss. It is found that loadings will affect the friction force and the mechanical loss of the triplet. The results show that the contact force and mechanical loss are dependent on the twist pitch. A shorter twist pitch can lead to higher contact force, while the trend of mechanical loss with twist pitch is complicated. The mechanical loss may be reduced by adjusting the twist pitch reasonably. The present model provides a simple analysis method to investigate the mechanical behaviors in multistage-structures under different loads.

关键词： Contact force Friction force Tension bending Mechanical loss

Effect of lamellar structural parameters on the bending fracture behavior of AA1100/AA7075 laminated metal composites

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Journal of Materials Science & Technology 2022年第4期99卷 28-38页

作者： Taiqian Mo Zejun Chen Dayu Zhou Guangming Lu Yongmeng Huang Qing Liu Joint International Research Laboratory for Light Alloys Ministry of EducationCollege of Materials Science and EngineeringChongqing UniversityChongqing 400044China Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing 210009China

The lamellar structure has an important impact on the mechanical properties of dissimilar laminated metal composites(LMCs),including the thickness ratio of dissimilar metal constituent layers and the number of ***1100 and AA7075 with thickness ratios of 1:4 and 3:4 were fabricated for multilayer AA1100/AA7075 LMCs by hot accumulative roll bonding(ARB)*** bending fracture characteristics of AA1100/AA7075 LMCs with different thickness ratios and numbers of constituent layers were *** research results indicated that AA1100/AA7075 LMCs with a low thickness ratio exhibited better bending ductility and toughness than those with a high thickness ratio,which was attributed to the crack growth resistance caused by the thickness of the soft AA1100 *** toughening mechanism introduced by crack deflection or arresting contributed to the enhancement in the toughness of the LMCs compared with that of the single 7075 Al *** bonding interfaces of AA1100/AA7075 LMCs with different numbers of layers are continuous and straight due to the high ARB temperature.A decrease in bending toughness was observed as the number of layers *** LMCs with a low number of layers,crack deflection or interface delamination is also considered a main toughening mechanism in dissimilar LMCs in addition to the thickness effect.

关键词： Laminated metal composite Mechanical properties bending Fracture behavior Toughening mechanism

Unveiling the Mechanism Behind the Asymmetric bending Compliance of Thin-Walled U-Shaped Strips:A Study Inspired by Plant Leaves

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Acta Mechanica Solida Sinica 2023年第1期36卷 156-165页

作者： Anran Wei Zhenbin Guo Fenglin Guo School of Naval Architecture Ocean and Civil Engineering(State Key Laboratory of Ocean Engineering)Shanghai Jiao Tong UniversityShanghai 200240China Institute of Semiconductor Manufacturing Research Shenzhen UniversityShenzhenGuangdong 518060China

Inspired by the shape of some plant leaves,we find that the thin-walled U-shaped strips exhibit different compliances under bending with opposite *** asymmetric bending compliance is attributed to the buckling of sidewalls of strips caused by the bending-induced *** the Euler-Bernoulli beam theory with the Kirchhoff-Love thin plate theory,a theoretical model is derived for the in-depth understanding of the sidewall *** pure bending,the critical moment applied to the strip for the sidewall buckling is found to be insensitive to the height,width and length of strip,which is the result of the compromise between the opposite geometric effects on the buckling behavior of sidewalls and the characteristics of cross *** the critical moment can be approximated as a linear function of flexural rigidity DEt^(3)/12(1-ν^(2)),where t is the wall thickness of strip,E is Young’s modulus,and v is Poisson’s *** predictions by our model agree well with the results obtained by finite element *** also investigate the buckling behavior of sidewalls for bending under transverse loads,considering the loading conditions of concentrated force and distributed *** study unveils the mechanism behind the asymmetric bending compliance of thin-walled U-shaped *** results would offer convenient guidance for the promising engineering applications related to this structure,such as the design of soft robots with enhanced locomotion performance.

关键词： bending Buckling Thin-walled beam Thin plate Bioinspired study

Effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on tensile and bending properties of high-Al-containing Mg alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 779-793页

作者： Sumi Jo Gyo Myeong Lee Jong Un Lee Young Min Kim Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Magnesium Korea Institute of Materials ScienceChangwon 51508Republic of Korea

This study investigates the effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on the uniaxial tensile and three-point bending properties of extruded Mg alloys containing high Al *** extruded Mg–9Al–1Zn–0.3Mn(AZ91)alloy contains lamellar-structured Mg_(17)Al_(12)discontinuous precipitates along the grain boundaries,which are formed via static precipitation during natural air *** extruded Mg–11Al–1Zn–0.3Mn(AZ111)alloy contains spherical Mg_(17)Al_(12)precipitates at the grain boundaries and inside the grains,which are formed via dynamic precipitation during *** to inhomogeneous distribution of precipitates,the AZ111 alloy consists of two different precipitate regions:precipitate-rich region with numerous precipitates and finer grains and precipitate-scarce region with a few precipitates and coarser *** AZ111 alloy exhibits a higher tensile strength than the AZ91 alloy because its smaller grain size and more abundant precipitates result in stronger grain-boundary hardening and precipitation hardening effects,***,the tensile elongation of the AZ111 alloy is lower than that of the AZ91 alloy because the weak cohesion between the dynamic precipitates and the matrix facilitates the crack initiation and *** bending,a macrocrack initiates on the outer surface of bending specimen in both *** AZ111 alloy exhibits higher bending yield strength and lower failure bending strain than the AZ91 *** bending specimens of the AZ91 alloy have similar bending formability,whereas those of the AZ111 alloy exhibit considerable differences in bending formability and crack propagation behavior,depending on the distribution and number density of precipitates in the *** bending specimens of the AZ111 alloy,it is found that the failure bending strain(ε_(f,bending))is inversely proportional to the area fraction of precipitates in the outer zone of bending specimen(A_(ppt)),with a relation

关键词： Mg–Al alloy Extrusion bending Precipitation Microstructure