MESOSCALE MODELING OF BALLISTIC IMPACT ON PLAIN WEAVE COMPOSITE

The goal of this work is to study energy absorbing mechanisms of plain weave composites. Experiments were conducted of 17-grain fragment simulating projectiles impacting singlelayer plain weave S-2 glass/epoxy composites. The focus of the experiments was on determining the ballistic limit velocity. A mesoscale finite element model was developed that includes woven fabric architecture. The mesoscale model includes tow-tow delamination modeled with the cohesive zone model using traction-separation laws determined from finite element models of cracking in fiber-matrix microstructure. The mesoscale model predicted ballistic limit velocity with 1% error. In contrast, a continuum model with effective plain weave properties predicted limit velocity with 6% error. The mesoscale model includes additional energy dissipation mechanisms such as tow-tow delamination, tow pullout, and frictional sliding, which are investigated. Finally, the single-layer model was extended to multi-layer composite penetration, and the impact versus residual velocities were compared with experimental results from the literature.