Analysis of bending force and springback behavior of metal-polymer-metal sandwich laminates

The bending and springback behaviors of sandwich laminates are more complex than those of monolithic sheet materials because of the differences between the properties of the core and skin materials. In this study, simplified analytical and numerical models were used for analyzing the springback angle and bending force of metal-polymer-metal sandwich laminates under bending. An analytical model was used to predict springback in three-point bending. The springback angles and bending force obtained from the numerical model correlated well with the experimental results. It was found that the finite element model using solid elements in the core was advantageous for predicting the shape after bending. It was demonstrated that these models can be used to design sandwich laminates with desired flexural stiffness by appropriately choosing the volume fraction. Potential weight reduction for sandwich laminates during the air bending process was presented.