Influence of the Deformation Rate on the Delamination of Laminated Composite Materials

Abstract

It is well known that delamination is one of the most critical mechanism of failure of laminated composite materials. It supposes an important load capacity reduction, it is difficult to see and his evolution modify the failure of the component. Composite delamination depends on their fracture toughness. On the other hand, impacts are the most dangerous loads for those materials due to the important deformation rate induced in the material. This work analyses the influence of load velocity in the fracture toughness, for modes I and II, in textile carbon/epoxy, up to an impact velocity of 0,190 m/s. For that range, results show that the mode I fracture toughness decrease with velocity, while for mode II it remains nearly constant. However, the load velocities analyzed are yet far from those induced in a low speed impact. We propose to continue this research by increasing deformation rates using drop tower impact techniques, to observe if the trend observed so far is maintained on increasing speed.