Equilibrium stability of a three-layered plate of functional-gradient material with a prestressed layer

We investigate the static stability of a composite elastic plate consisting of three layers of a functional gradient material. The middle layer is pre-deformed in two directions and rigidly attached to the external initially non-stressed layers. A linearized boundary conditions and linearized equilibrium equations are obtained. The derived system of partial differential equations is solved numerically. In the space of strain parameters we obtain the zone of stability. The influence of various models of a functionally gradient material on the stability is analyzed.