A series of instrumented impact tests have been carried out using two different CFRP laminates, IM6/937 with a relatively brittle matrix and T800H/3900-2 with a toughened matrix. Two impactor masses differing from each other by a factor of 20 were used to study the effect of impact velocity and rate of loading.
Differences in the target impact response were found when the panels were impacted with the same energy but at different velocities. The higher velocities led consistently to slightly higher measured peak forces, but lower maximum deflections. This difference is reflected in the resultant damage state. The measured delamination area is larger for the high-mass impacts at the same incident impact energy, particularly for the tough matrix system. However, when the delamination size is correlated with the impactor energy loss, the mass effect disappears. The low-mass, high-velocity impacts create large contact forces, which leads to significant fiber breakage on the impact face. Fiber breakage throughout the rest of a panel is lower, which can be explained by the lower maximum panel deflections observed in low-mass impacts. An energy balance that takes into account the work done in delamination and fiber breakage gives good agreement with the measured impactor energy loss over the complete range of impact energies tested.