Thermoelastic Damping in Bilayered Microbeam Resonators with Annular-cross Section

The design of high quality factor (Q-factor) resonator requires consideration of thermoelastic damping (TED), which is an internal energy dissipation mechanism and determines the upper limit of the Q-factor. The previous works of TED models for microbeams mainly focus on the microbeams with rectangular or circular cross-section. Thus, there is a lack of study aiming at the microbeam with annular cross-section. In this paper, a TED model for the bilayered microbeam with annular cross-section is proposed on basis of Zener's theory and Green function method. The constraints of microbeam is cantilevered and excited by axial sinusoids. The results calculated by the present model agree well with those obtained by the finite element method (FEM) model, proving the validity of predicting TED values for bilayered microbeam.