Shahid Rajaee Teacher Training University (SRTTU) Journal of Computational & Applied Research in Mechanical Engineering (JCARME) 2228-7922 7 1 2017 08 01 The effect of small scale and intermolecular forces on the nonlinear Pull-in instability behavior of nano-switches using differential quadrature method 109 125 639 10.22061/jcarme.2017.639 EN Seyyed Mohammad Fatemi Mechanical Engineering Department, Shahrekord University, Shahrekord, Iran Yaghoub Tadi Beni Faculty of Engineering, Shahrekord University, Shahrekord, Iran Journal Article 2016 04 30 Using differential quadrature method, this study investigated pull-in instability of beam-type nano-switches under the effects of small-scale and intermolecular forces including the van der Waals and the Casimir forces. In these nano-switches, electrostatic forces were served as the driving force, and von-Karman type nonlinear strain was used to examine nonlinear geometric effects. To derive nonlinear governing equations as well as the related boundary conditions for the nano-beam, variation method was used. Besides, to study the influence of size effect, the nonlocal elasticity theory was employed and the resulting governing equations were solved using differential quadrature method. Finally, the pull-in parameters were studied using the nonlocal theory and the results were compared with the numerical results of the classical continuum theory as well as experimental results contained in the references. Results demonstrated that taking into consideration the von-Karman type nonlinear strain increases the beam stiffness and hence, the pull-in voltage. Besides, use of the small scale, compared with the classical theory of elasticity, yields results much closer to experimental results. https://jcarme.sru.ac.ir/article_639_f11271896958e0f695a3a15e441a4e60.pdf