Skin-core adhesion in high performance sandwich structures

The aim of this study is to characterize the interfacial fracture toughness of a micro-lattice core based sandwich structure from quasi-static to dynamic rates of loading. The modified three-point bend (MTPB) sandwich beam was used to characterize the interfacial properties of these sandwich structures. Dynamic tests were undertaken of up to 3 m/s using a purpose-built instrumented drop-weight impact tower. Data reduction was accomplished through the use of a compliance calibration procedure similar to that used for characterizing the delamination resistance of composites. The flexural properties of sandwich beams were investigated through three-point bend tests at a cross-head displacement rate of up to 3 m/s. A detailed examination of the impact region highlighted the failure processes in these systems and this was related to the data from the quasi-static flexural tests. The globalized deformation and energy absorption during progressive were also discussed.