Thermoelastic damping in micromechanical circular plate resonators with radial pre-tension

Abstract

Thermoelastic damping (TED) is one of the main energy dissipation mechanisms in micro/nano resonators and one of the major concerns in respect to performance of micro-electromechanical systems and nano-electromechanical systems devices. In this article, we report that application of pre-tension stress on micro/nano circular plate resonators not only increases the resonant frequency, but also reduces TED. Analytical expressions of TED in micro-plate resonators, subjected to uniform radial pre-tension stress around its edge, are derived by means of thermal energy method. Thermal conductions along both the thickness direction and the radial direction are taken into account. TED obtained by using 2-D thermal conduction model is expressed in the form of infinite series and the convergence of the series is also discussed. Numerical results show that application of pre-tension is able to considerably reduce TED of micro-plate resonators. The effects of the dimensions, ratio of thickness to radius and vibration modes of circular plate resonators on TED are examined. This study indicates that application of pretension in micromechanical resonators could be a viable means to modulate resonant frequency and TED.