Thermo-electro-mechanical buckling analysis of sandwich nanocomposite microplates reinforced with graphene platelets integrated with piezoelectric facesheets resting on elastic foundation

This paper investigates on the buckling treatment of a three layered rectangular nanocomposite microplate resting on elastic foundation. The core is a laminated nanocomposite layer reinforced with graphene platelets bonded with two piezoelectric facesheets. The microplate is subjected to thermo-electro-mechanical loads. The governing equations are developed in the framework of the first order shear deformation theory alongside with the modified couple stress theory. The effective laminated nanocomposite core layer thermo-mechanical properties are determined by the Halpin-Tsai micromechanical model. The Ritz method is employed to discretize the governing equations of motion in order to achieve the buckling loads for different boundary condition types. The outcomes are developed for both thermo-electrical and electro-mechanical buckling examinations. For the latter case, the microplate is studied when it is subjected to uniaxial, biaxial, and shear mechanical loads. The effects of boundary condition types, the external applied voltage, the graphene platelet distribution pattern, the elastic foundation parameters and the graphene platelet weight fraction as well as its geometrical features on the buckling loads are studied. The results reveal that the types of boundary condition, the graphene platelet dispersion pattern, the graphene platelet weight fraction, and the applied voltage affect noticeably the thermal/mechanical buckling load. Moreover, when the elastic foundation effect is considered the increment percent in the thermal and shear mechanical buckling loads is not affected by the graphene platelets dispersion pattern while for some certain boundary condition types, the graphene platelets distribution pattern affects the increment percent of the critical uniaxial and biaxial mechanical loads.