Experimental and simulation of polyurea/CFRP composite structures were studied under high speed impact of projectile

With the development of composite structures, polyurea materials can be used to improve the protective performance of multilayer composite structures subjected to explosion or impact. In order to study the penetration resistance of polyurea sprayed CFRP composites, the fragment penetration loading test was carried out with a 14.5mm ballistic gun. The influence of polyurea coating position on the dynamic response of polyurea/CFRP composite structures were analyzed and discussed by test and numerical simulation. The results showed that polyurea coating on the back surface of CFRP can reduce the damage of CFRP and reduce the residual velocity of fragments compared with bare CFRP. The numerical simulation results were in good agreement with the experimental results, which showed that the numerical method can accurately simulate the penetration of fragment into polyurea/CFRP composites structure. The simulation results showed that the energy absorption of polyurea was increased as polyurea was sprayed on the back of CFRP. The lower the fragment initial velocity, the greater the contribution of polyurea for improving the penetration resistance of structure. The large tensile deformation and damage of fiber under the process of penetration can be seen by numerical simulation, revealing that the anti-ballistic mechanism of polyurea.