On the snap-through instability of post-buckled FG-CNTRC rectangular plates with integrated piezoelectric layers

The present paper deals with postbuckling characteristics of carbon nanotube reinforced composite (CNTRC) rectangular plates with integrated piezoelectric layers subjected to in-plane compressive loads. The von Karman type of geometrical nonlinearity is taken into consideration to account for the large deformations of the plate. The dispersion of CNTs may be uniform or functionally graded and the distribution of electric potential across the thickness of piezoelectric layers is simulated by a combination of linear and sinusoidal functions. Generalized differential quadrature method is employed to discretize nonlinear stability equations, boundary conditions and Maxwell equation and then nonlinear system of equations is solved using a displacement control strategy. A comprehensive parametric study is presented to provide an insight into effects of CNT dispersion and volume fraction, geometrical parameters, type of in-plane load, boundary conditions, thickness of piezoelectric layers and external applied voltages on the postbuckling behaviors of the nanocomposite plate. It is shown that snap-through type of instability, which is known as secondary instability, occurs during postbuckling regime. It is revealed that both volume fraction and dispersion of the CNTs could affect the snap-through characteristics of the plate. It is found that snap-through instability is sensitive to thickness of the piezoelectric layers.