Modeling the effects of material properties on the pull‐in instability of nonlocal functionally graded nano‐actuators

Dynamic pull‐in behavior of nonlocal functionally graded nano‐actuators by considering Casimir attraction is investigated in this paper. It is assumed that the nano‐bridge is initially at rest and the fundamental frequency of nano‐structure as a function of system parameters is obtained asymptotically by Iteration Perturbation Method (IPM). The effects of actuation voltage, nonlocal parameter, properties of FGM materials and intermolecular force on the dynamic pull‐in behavior are studied. It is exhibited that two terms in series expansions are adequate to achieve the acceptable approximations for fundamental frequency as well as the analytic solution. Comparison between the obtained results based on the asymptotic analysis and the reported experimental and numerical results in the literature, verify the effectiveness of the asymptotic analysis.