Interfacial damage analysis of shallow spherical shell with FGM coating under low velocity impact

Interfacial damage would seriously reduce the structures' property, especially structures with coating when under dynamic loading. In this paper, the interfacial damage of shallow spherical shell with functionally graded material (FGM) coating subjected to low velocity impact is studied. An interfacial damage analytical model is established based on the continuum theory-based interfacial damage constitutive relations. The A.E. Giannakopoulos's 2-D functionally graded material (FGM) contact model is applied to predict contact force. Motion equations for shallow spherical shell substrate and FGM coating are obtained by Reissner variation, respectively, and the dynamic analytical model is established by using interfacial connection relations to relate the motion equations for FGM coating and those for elastic shallow spherical substrate. The orthogonal collocation point method, the Newmark method and iterative method are used synthetically to solve the whole question. In numerical examples, the dynamic response of shallow spherical shell with FGM coating and contact force are obtained, and the effects of material and geometrical parameters of FGM coating on interfacial damage and contact force have been discussed.