Experimental results of medium velocity impact tests for reinforced foam core braided composite structures

Abstract

Absorbing impact energy at subsystem level is an attractive idea that is emphasized by new composite reinforcement techniques such as stitching or pinning. This paper reports experimental results of medium velocity impact tests carried out on several arrangements of reinforced foam/braided composite structures. The tests consisted of a steel ball shot at a velocity of 110 m/s from a gas gun impacting the structures on their leading edge. Post-mortem tomography analysis delivered very rich information which shed light on the damage mechanisms that the composite structures underwent. In addition, two fast-speed cameras were used to derive the energy absorption during the impact. Absorption capabilities were also compared with those of dynamic crushing tests (reported in a companion paper) and some designs clearly exhibited promising behavior as shock absorbers.