Composite tube under low velocity impact

Advanced applications of tubes made of carbon-epoxy composites in which the main external load is torque, have been recently developed in the industrial and sports fields. In order to use these high specific performance material components, a fundamental problem for the designer is the low energy and velocity impact behavior. In fact such load events are very common during normal service life and their real effects on in-service component behavior are not well understood. In the present work the results of an experimental test campaign performed with the aim of evaluating the mechanical behavior of tubular structures under impact, with and without torsional pre-load, are presented. In particular, the aspects on which the research was focused are the stacking sequence and the pre-load level, that proved to be a key factor for the impact response of the material. A numerical model based on the Ansys software was developed to describe the material behavior up to the first load drop.