Material Tests and Mesoscale Computer Model for Ballistic Impact on Carbon Fiber Composite

Two-dimensional (unidirectional) and 3-D woven carbon fiber reinforced plastic (CFRP) panels were produced by Albany Engineered Composites. Coupons were machined from the laminates for various mechanical tests in tension, torsion, and delamination. A batch of neat resin was also produced and the mechanical properties of the resin were determined. Some of the mechanical tests were performed at medium and high strain rates. The panels were tested under ballistic impact while recording the back face deflection with a stereo pair of high-speed cameras to perform digital image correlation. Additionally, an ultra-high-speed camera provided a better resolution of the initial (50 is) pyramid that forms after impact. The mechanical tests were used to determine the material properties of the constituents as well as the strength of the interface between matrix and fibers. The properties were incorporated in material models in LS-DYNA to perform simulations of the mechanical tests as well as the ballistic experiments. The ballistic limits, residual velocities, and deflection histories served as a validation of the model and were predicted with good accuracy for two thicknesses of the two-dimensional composite and one of the 3-D composite.