Ballistic performance of quasi-isotropic CFRP laminates under low velocity impact

Abstract

The perforation characteristics of fiber reinforced laminates is crucial for the design of protective civil and military structures. This paper investigates the perforation characteristics (ballistic limit velocity, residual velocity, perforation energy) of cross ply and quasi-isotropic (QI) carbon fiber reinforced polymer (CFRP) laminates under the impact of a rigid conical steel bullet. The influence of thickness and ply orientation on these characteristics is also studied for a wide range of velocities. The perforation characteristics of these laminates were determined, numerically as well as experimentally. A numerical model is developed by using Hashin damage model to understand the behavior of laminates under high velocity impact. The accuracy of the model is assessed by comparing its prediction with experimental results of cross ply laminates. Then, impact perforation study of different possible configurations made of quasi-isotropic (QI) CFRP laminates, oriented at 0°, 90°, 45° and −45° directions are carried out with the help of validated numerical model. The perforation characteristics predicted with the help of numerical model is in good agreement with the experimental results. Optimal configuration is achieved in terms of energy absorption and damage resistance for better performance under impact loading.