Divergence Instability of an Extensible Microplate Subjected tononlinear Electrostatic Pressure

摘要

An improved mathematical model in order to study mechanical behavior of an extensible microplate subjected to nonlinear electrostatic pressure was presented. In this model, the effect of stretching due to fixed boundary conditions and residual stresses because of fabrication process on static instability of the microplate was studied. The derived nonlinear partial integro-differential governing equation considering stretching and residual stresses effects, using of Step-by-Step Linearization Method (SSLM), was linearized. By applying the finite difference method (FDM) to a rectangular mesh, the linearized equation was discretized. By considering the stretching stresses effect, the present mathematical model shows a highly reasonable prediction of divergence instability as compared with previous existing model. The obtained results show that the residual stresses have considerable effects on Pull-in phenomenon. Axial stresses due to stretching and tensile residual stresses increase pull-in voltage and compressive residual stresses decrease it.