The influence of nanoparticles embedded in a matrix on the responses of composite structures to low velocity impacts

摘要

In passive safety structures, the use of composite materials has increased significantly for many years because of their high specific properties and high energy absorption capacities. The purpose of this experimental study was to describe the behavior of Kevlar woven composite materials under low-velocity impacts. Different matrices (with and without nano-reinforcement) were considered. The role of the nano-reinforcement is to bring significant improvement with low concentration, thereby avoiding sacrificing other desirable properties. Tests were performed with a drop-weight tower on square plates clamped in a circular fixture. A video camera fixed underneath the plate during impact was used to record the damage that occurred during impact. Macroscopic impact scenarios were proposed based on the correlations between the photographs, displacement, and loading histories. Cross sections of the damaged areas were inspected with an optical microscope in order to reveal the micro-mechanisms that were involved in the dissipation of the impact energy.