Three-dimensional exact solutions of double-coated structure with arbitrary thickness under normal point load.

• The exact solution of three-dimensional multilayer structure with arbitrary thickness under point load is derived. • The analytical method can clearly predict the critical load of interface shear delamination failure. • The stresses and displacements of the substrate, adhesive, and adherend are presented by explicit closed-form expressions. Explicit closed expressions of stresses and displacements of an adherend and an adhesive provide researchers and designers with insight into the effects of variable parameter properties on structural performance. Through potential theory method, the Green's functions of a double-coated structure under normal point load are solved using the mirror image method, where the mirror image rule satisfies the recursion law of the Fibonacci sequence. The stress distribution of the multilayer structure under the action of point load is presented in the form of an infinite series with a fast convergence rate. A guideline for the design of coating thickness and material parameters to reduce interfacial stress is developed (reduce adhesive thickness, reduce elastic modulus of adherend, increase elastic modulus of adhesive). The accuracy of the exact solution is demonstrated through comparison with contact analytical solutions. In addition, the critical load of interface shear delamination failure is predicted. The stresses and displacements of the adherend and the adhesive are presented with the solutions, which can serve as a reference for researchers and designers. [Display omitted] [ABSTRACT FROM AUTHOR]