▎ 摘　　要

Microelectromechanical systems (MEMS) have attracted researchers' attention due to their various applications. Microplates with piezoelectric face sheets are the impending choice for MEMS. Hence, in this paper, an analysis of free vibrations of such microplates reinforced with graphene platelets resting on an elastic foundation and subjected to an external voltage in a thermal ambient is performed. The first-order shear deformation theory and a modified couple stress theory are employed to derive their kinetic and strain energies. The thermomechanical features of the core layer, reinforced with graphene platelets, are determined using the Halpin-Tsai micromechanical model. The Ritz technique is used to find the associated natural frequencies for different boundary conditions. The impact of geometry of graphene platelets, their weight fraction, temperature increment, external voltage, and boundary conditions on the outcomes are examined. The results obtained showed that decrement of the fundamental natural frequency of the microplates depends on the increment of temperature.