Experimental Study of Tensile Preloading Influence on the Mechanical Behaviour of Pseudo-Ductile Hybrid Composite under High-Velocity Impact

Abstract

The hybridisation of fibre-reinforced plastics is one of the perspective technological methods that make it possible to reduce the sensitivity of polymer composites to stress concentration and increase their damage tolerance. In this case, hybridisation means a combination of different types of reinforcing fibres in one yarn, one layer or one package. In most published papers, the authors investigated the mechanical behaviour of hybrid fibre-reinforced plastic under static loading or low-velocity impact conditions only. At the same time, statically preloaded structures made of composite materials can also be subjected to high-velocity impact. Tensile or compressive preloading affects not only the amount of energy absorbed by the composite but also changes the deformation and fracture pattern. This paper presents the results of the experimental study of the mechanical behaviour of a woven carbon/aramid hybrid composite under tensile preloading and high-velocity impact. Pre-tensioned specimens of homogeneous and hybrid composites were subjected to a high-velocity impact by a steel spherical projectile with the velocities up to 900 m/s. The experimental results showed that the hybrid composite had the lowest sensitivity of the ballistic limit to the tensile preloading.