Experimental Method for Mode I Dynamic Fracture Toughness of Composite Laminates Using Double Cantilever Beam Specimens

摘要

To perform predictive crash simulations on composite structures, it is necessary to provide reliable input data for the cohesive material models often used to describe delamination processes in composite materials. For quasi-static loadings, the mode I fracture toughness measurement has been standardized. However, for high-rate of loading, additional challenges arise. Consequently, no test standard has yet been defined for the mode I fracture toughness evaluation under high rates of loading. Therefore, this research aims at developing an experimental procedure to characterize the dynamic fracture toughness of a fast running crack in carbon fiber-reinforced epoxy matrix composite T700/M21. The dynamic fracture toughness is characterized using the Double Cantilever Beam test under several loading rates up to 17 m.s~(-1). An experimental protocol has been developed to identify the dynamic energy release rate GID for the mode I crack opening with various crack speeds a.