Analysis of deflection, natural frequency and damping of microactuators reinforced by SWCNT under electric actuation

This paper studies the static deflection, natural frequency and the quality factor of structural damping in the microactuators made from single wall carbon nanotubes reinforced polymers. The microactuator is assumed as a clamped–clamped microbeam under electrical load, and it has been assumed that the midplane of the microbeam is stretched when it is deflected. The microbeam has viscoelastic damping due to its polymeric structure, and is modeled as the Kelvin–Voigt model. The equation of motion has been derived using the Newton’s second law. The static deflection and natural frequency have been obtained using Galerkin method, and the quality factor of viscoelastic damping has been obtained using the strained parameter perturbation method. Also, the quality factor of thermoelastic damping of system was estimated using the theory derived in previous works. It has been shown that using single wall carbon nanotubes reinforced polymers, one may construct a microactuator with resonance frequency larger than the resonance frequency of the current microactutaor where their deflections are the same. It is a much desirable property in the design of microswitches and microresonators. Also, it shows that in this system the structural damping is larger than its value in the current microresonators made from silicon, which is an undesirable property.