1. Static and dynamic instability of nanowire-fabricated nanoelectromechanical systems: effects of flow damping, van de Waals force, surface energy and microstructure
- Author
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Keivani, Maryam, Koochi, Ali, Abadian, Naeime, Rezaei, Morteza, and Abadyan, Mohamadreza
- Subjects
Electromechanical devices -- Properties -- Analysis ,Surface energy -- Analysis ,Damping (Mechanics) -- Analysis ,Microstructure -- Analysis ,Physics - Abstract
Surface energy and microstructure-dependent size phenomena can play significant roles in physical performance of nanoelectromechanical systems (NEMS). Herein, the static and dynamic pull-in instability of cantilever and double- clamped NEMS fabricated from conductive cylindrical nanowires with circular cross section is studied. The Gurtin-Murdoch surface elasticity in combination with the couple stress continuum theory is employed to incorporate the coupled effects of surface energy and microstructure-dependent size phenomenon. Using Green-Lagrange strain, the higher order surface stress components are incorporated into the governing equation. The effect of gas damping is considered in the model as well as structural damping. The nonlinear governing equation is solved using analytical reduced order method. The effects of various parameters on the static and dynamic pull-in parameters, phase plans, and stability threshold of the nanowire-based structures are demonstrated. Key words: couple stress theory, surface effect, cylindrical nanowire, dynamic pull-in instability, gas damping. L'energie de surface et les phenomenes de taille a dependance micro-structurelle peuvent jouer des roles importants dans les performances physiques de systemes nanoelectromecaniques (NEMS). Ici, nous etudions l'instabilite de collage, statique et dynamique, des NEMS cantilevers et clampes deux fois, fabrique a partir de nanofils cylindriques conducteurs a section circulaire. Nous utilisons l'elasticite de surface de Gurtin-Murdoch avec la theorie du second gradient pour incorporer les effets couples de l'energie de surface et des phenomenes de taille a dependance micro-structurelle. Utilisant l'approche de Green-Lagrange pour les deformations, nous incorporons les composantes d'effort de surface d'ordre eleve dans les equations directrices. Notre modele inclut les effets d'amortissement dus au gaz, ainsi qu'a la structure. L'equation directrice non lineaire est solutionnee en utilisant une methode d'ordre reduit analytique. Nous demontrons les effets des differents parametres sur l'instabilite de collage, statique et dynamique, sur les plans de phase et sur le seuil de stabilite des structures basees sur le nanofil. [Traduit par la Redaction] Mots-cles: theorie de l'effort de surface, effet de surface, nanofil cylindrique, instabilite de collage dynamique, amortissement du augaz. PACS Nos.: 85.85.+j, 62.23.Hj, 46.70.De, 05.45.-a., 1. Introduction Micro- and nanoelectromechanical systems (NEMS) are increasingly used in various engineering and science branches (i.e., mechanics, chemistry, optics, biology, electronics, etc.). Nowadays, nanoNEMS are used to develop nanodevices [...]
- Published
- 2016
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