Nonlinear thermal postbuckling of functionally graded graphene-reinforced composite laminated plates with circular or elliptical delamination

This research investigates the nonlinear thermal stability responses of functionally graded graphene-reinforced composite (FG-GRC) laminated plates with embedded circular and elliptical delamination as well as edge delamination, subjected to a uniform temperature rise and a variety of mechanical boundary conditions. The thermomechanical properties of the GRCs are estimated using the extended Halpin-Tsai micromechanical model that incorporates efficiency parameters to take into account nanoscale size and surface effects of the graphene reinforcement. The von Karman geometrical nonlinearity is adopted in a solution based on the third-order shear deformation theory. The nonlinear equilibrium equations derived by the minimum total potential energy principle are solved using the Ritz method in conjunction with the Newton-Raphson iterative procedure. Parametric studies reveal that the types of graphene distribution pattern and geometry of delamination zones have a substantial effect on the thermal equilibrium paths and buckling temperature of the GRC delaminated plates. FG-X graphene sheet pattern raises the critical buckling temperature and compressive strength of the baselaminate and reduces the nonlinear thermal postbuckling deflection; however, it causes a significant increase in normal stress distribution at the top and the bottom surfaces of the delaminated plates.

Automated summary

This research investigates the nonlinear thermal stability responses of functionally graded graphene-reinforced composite (FG-GRC) laminated plates with embedded circular and elliptical delamination as well as edge delamination. The study reveals that the types of graphene distribution pattern and geometry of delamination zones have a substantial effect on the thermal equilibrium paths and buckling temperature of the GRC delaminated plates.