Impact-Induced Damage Progression in 2-D and 3-D Woven Composite Systems

The role of fabric architecture on the impact-induced damage progression and perforation resistance of glass-fiber reinforced vinyl-ester resin panels under dynamic loading condition is investigated. Three fabric preforms are considered: a 2-dimensional, plain-woven laminate, a commercially available biaxially reinforced warp-knit, and a 3-dimensional, orthogonally woven preform. Composite samples are subjected to multiple impacts, until perforation, and the impactor position and acceleration are monitored throughout each event, resulting in a visualization of dynamic energy dissipation. Failure modes of the various material systems are characterized. The radial damage expansion was smallest for the 2-d laminate, larger for the biaxially-reinforced warp-knit, and largest for the 3-d orthogonal woven composite. The 3-d composite survived more hits and dissipated more total energy than the other systems. The difference may be due to the additional energy absorption mechanisms, which involve the crimped portion of z-tows in the 3-d composites. This implies that failure may be controlled by manipulation of the properties of the z-tows. It also indicates that the surface condition of 3-d orthogonally woven composites can strongly affect the progression of impact-induced damage.