Size-Dependent Postbuckling Behavior of FG Nanocomposite Microbeam Modeled in the Framework of MCST Considering Various Boundary Conditions

In this paper, postbuckling of functionally graded (FG) nanocomposite Timoshenko microbeam has been investigated. Using an adjusted micromechanics model of nanofillers, the effective elastic modulus of the structure is determined. The considered distribution scheme of graphene platelets (GPLs) consists of three different type schemes. To access the size-dependent nonlinear differential governing equations, assumptions of Timoshenko’s theory and a nonclassical theory named modified couple stress theory (MCST) have been utilized. After that, both sets of nonlinear governing equations and related boundary equations of microbeam are discretized exerting generalized differential quadrature method (GDQM) accompanied by a classic iteration technique to reach the buckling and postbuckling forces. The impact of diverse parameters including dimensional, size effects, GPLs-related properties and boundary edges’ type on buckling and postbuckling response of microbeam are propounded in detail. The results of this research indicate how the small scale and the GPLs-related properties simultaneously affect the postbuckling behavior of structure.