The effect of the arrangement of corrugated composite on the R-curve of the sandwich structures with hybrid corrugated/foam core under mode I loading

The application of the sandwich structures in industries such as aircrafts and wind turbine blades has had a significant growth over the years due to the high bending stiffness to weight ratio these structures provide. Of the main parameters in the design of these structures is the fracture resistance. In this research, the debonding of the face sheet and core in the sandwich structures with hybrid corrugated/foam core is experimentally investigated on asymmetric DCB specimens. The value of strain energy release rate (G) of the specimens with various corrugated composite arrangements in core is calculated based on the compliance method. Eventually, the effect of the amount of composite area on the interface between face sheet and core on the R-curve behavior is investigated. Moreover, the effect of the occurrence of fiber bridging phenomena is studied on the trend of the R-curve of the aforementioned specimens. The results represent that the presence and increase of the corrugated composite area in the interface between face sheets and core significantly increases the fracture toughness of these structures compared to the case where there is just foam area in the interface.