Bending response of sandwich panels with graded core: 3D elasticity analysis

Sandwich panels are used in a wide variety of applications including aircraft, aerospace, naval/marine, construction, and transportation industries where strong stiff and light structures are required. Due to the mismatch of properties between the face sheets and the core, stress concentrations can occur at these interfaces, often leading to delamination, which is a major concern. One solution to this problem is the introduction of a functionally graded core, in which the properties vary gradually from the face sheets to the center, thus eliminating any abrupt changes in properties. This paper presents the results of an investigation into the behavior of sandwich panels, with stiffness of the core graded in the thickness direction, on the basis of the recently developed 3D elasticity solution. The use of graded core to improve performance of sandwich structures, especially under localized loading, is examined and discussed.