It is not easy to isolate the damage mechanisms associated with low-velocityimpact in composites using traditional experiments. In this work, a new experiment ispresented with the goal of generating data representative of progressive damageprocesses caused by low-velocity impact in composite materials. Carbon fiberreinforced polymer test specimens were indented quasi-statically such that a biaxialbendingstate of deformation was achieved. As a result, a three-dimensional damageprocess, involving delamination and delamination-migration, was observed anddocumented using ultrasonic and x-ray computed tomography. Results from twodifferent layups are presented in this paper. Delaminations occurred at up to threedifferent interfaces and interacted with one another via transverse matrix cracks.Although this damage pattern is much less complex than that of low-velocity impacton a plate, it is more complex than that of a standard delamination coupon test andprovides a way to generate delamination, matrix cracking, and delamination-migrationin a controlled manner. By limiting the damage process in the experiment to threedelaminations, the same damage mechanisms seen during impact could be observedbut in a simplified manner. This type of data is useful in stages of model developmentand validation when the model is capable of simulating simple tests, but not yetcapable of simulating more complex and realistic damage scenarios.
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