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1.
We present uniaxial tensile test results for 30–50 nm thick freestanding aluminum films. Young’s modulus and ductility were found to decrease monotonically with grain size. Reverse Hall–Petch behavior was observed with no appreciable room temperature creep. Non-linear elasticity with small irreversible deformation was observed for 50 nm thick specimens. 相似文献
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Analytical model of displacement amplification and stiffness optimization for a class of flexure-based compliant mechanisms 总被引:1,自引:0,他引:1
The paper formulates an analytical method for displacement and stiffness calculations of planar compliant mechanisms with single-axis flexure hinges. The procedure is based on the strain energy and Castigliano’s displacement theorem and produces closed-form equations that incorporate the compliances characterizing any analytically-defined hinge, together with the other geometric and material properties of the compliant mechanism. Displacement amplification, input stiffness and output stiffness calculations can simply be performed for any serial compliant mechanism. The class of amplifying compliant mechanisms that contain symmetric corner-filleted or circular flexure hinges is specifically addressed here. A parametric study of the mechanism performance is performed, based on the mathematical model, and an optimization procedure is proposed, based on Lagrange’s multipliers and Kuhn-Tucker conditions, which identifies the design vector that maximizes the performance of these flexure-based compliant mechanisms. Independent finite element simulation confirms the analytical model predictions. 相似文献
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微型电磁继电器的制作和仿真分析 总被引:4,自引:0,他引:4
介绍了一种基于MEMS技术的微型电磁继电器的制作过程和仿真分析.这种微继电器的大小约是4mm×4mm×0.5mm,主要采用普通的微加工技术来完成全部制作工艺.与传统继电器相比,这种继电器采用平面线圈来代替螺线管线圈,有利于MEMS工艺,并且提出了一种双支撑的悬臂梁结构做为活动电极,具有较高的灵敏性和稳定性.另外,还进行了一些有关线圈通过激励电流后对活动电极产生电磁力的理论计算和仿真分析,利用这些结果可以对这种电磁继电器的结构和参数进一步优化. 相似文献
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Sungho Jin 《Journal of Electronic Materials》2003,32(12):1366-1370
In packaging of microelectromechanical systems (MEMS), optical, and electronic devices, there is a need to directly bond a
wide variety of inorganic materials, such as oxides, nitrides, and semiconductors. Such applications involve hermetic-sealing
components, three-dimensional MEMS assembly components as well as active semiconductor or optical components, dielectric layers,
diffusion barriers, waveguides, and heat sinks. These materials are known to be very difficult to wet and bond with low melting-point
solders. New Sn-Ag- or Au-Sn-based universal solders doped with a small amount of rare-earth (RE) elements have been developed,
which now allow direct and powerful bonding onto the surfaces of various MEMS, optical, or electronic device materials. The
microstructure, interface properties, and mechanical behavior of the bonds as well as the potential packaging applications
of these new solder materials for MEMS and optical fiber devices are described. Various packaging-related structural, thermal,
or electrical issues in MEMS are also discussed. 相似文献
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PCR芯片和生化微分析系统 总被引:1,自引:0,他引:1
介绍了PCR微芯片的最新研究进展,给出了不同结构的PCR芯片设计原理以及特点,介绍由PCR芯片为主要单元的集成微全分析系统的相关研究,同时简要介绍了对PCR的仿真模拟等。 相似文献
10.
Recent experiments have shown that metallic materials display significant size effects when the characteristic length scale of non-uniform plastic deformation is close to a micron. Couple stress plasticity has been developed to explain such phenomena by Fleck and Hutchinson. The mechanical behaviors of ultra-thin nickel beams in different boundary conditions were studied with the hybrid element developed for couple stress plasticity before. Strong scale effects are found when the beam's thickness is close to the material characteristic length scale. Such phenomena will disappear if the beam' s thickness is greatly larger than the material characteristic length scale. The scale effect is the beams inherent property and it does not change with the change of support conditions. 相似文献