Effects of interface stiffness and delamination on resonant oscillations of metal laminates

In the present study, the effects of the interface stiffness and delamination of the metal laminates were investigated. In the modal analysis, the natural oscillation mode of the laminate consisting of two copper sheets with various interface conditions was analyzed by using a finite element method. The interface delamination decreases the natural frequency for the out-of-plane oscillation mode whereas it has no effect on that for the in-plane mode. The interface stiffness affects the natural frequency for both the out-of-plane and in-plane modes. Its influence was more obvious when the stiffness is lower than that of the matrix for the out-of-plane mode whereas there was an opposite trend for the in-plane mode. In the experiment, the resonant frequency of two copper sheets bonded by the adhesive was measured. As well as the simulation, the lower interface stiffness and the interface delamination decreased the resonant frequencies