Damage mechanics from high velocity micro-particle impacts on polyethylene tape.*

Understanding damage mechanics is important when designing materials that will be exposed to high velocity particle impacts, such as polymer-based erosion coatings for helicopter rotor blades or impact shields for satellites. Here, we investigate the high-velocity impact deformation response of ultra-high molecular weight polyethylene (UHMWPE) tape to determine the fundamental impact dynamics and to evaluate how material processing can modify the tape’s mechanical behaviors. Using a laser-induced projectile impact test, we conduct impact experiments using steel particles (~15-30 μm diameter) against UHMWPE tape with linearly structured fibrals at velocities up to 500 m/s. The particles are monitored pre- and post-impact with an ultra-high-speed 16-frame camera with nanosecond time resolution. Post-mortem damage morphologies are assessed as a function of particle impact speed. Based on real-time and post-mortem observations, we discuss the damage mechanisms of the UHMWPE tape under supersonic micro-particle impacts.