Ballistic performance and damage analysis of CFRP laminates under uniaxial pretension and precompression

This study investigated the perforation of Carbon Fiber Reinforced Plastic (CFRP) laminate plates by rigid spheres at various impact velocities. The ballistic impact tests were conducted under three preloading conditions: uniaxial tension, uniaxial compression, and no preload. A one-stage gas gun accelerated rigid steel sphere projectiles to velocities between 195 m/s and 782 m/s. A high-speed camera was employed to capture the impact and residual velocities of the projectiles. Sufficient experimental data was obtained to fit accurate ballistic limits using the Lambert-Jonas ballistic equation. Experiment results showed that both pretension and precompression decreased the ballistic limit velocity of the testing plates. Energy absorption declined sharply when the impact velocity exceeded the ballistic limit velocity, then remained stable at about 30%. Failure modes were analyzed based on surface and cross-sectional damage observations. A theoretical model based on energy absorption was developed to predict the effect of preloading conditions on the ballistic limit.