Residual Strength Characterization of Laminated Composites Subjected to Impact Loading
SourceAn analogy between damage inflicted by a single-point hard-particle impact and damage inflicted by inserting a flaw of known dimensions in a static tensile coupon is discussed. The results suggest that residual strength can be predicted as a function of kinetic energy of impact by executing two experiments, a static tension test on an unflawed specimen and a static tension test on a coupon previously subjected to a single-point impact. The model appears to be accurate for impact velocities which are less than the penetration velocity. For velocities above complete penetration, the residual strength is identical to the static strength of a coupon with a hole having the same diameter as the impacting particle. Comparison of various materials indicates that the impact strength of composite materials is strongly influenced by the strain energy to failure of the reinforcement.