Research On The Impact Behavior And Dynamic Strength Of 3-D Woven Composite

With the development of science and technology, three dimensional woven composites are widely applied in astronautics and other high-tech fields. In practical applications, structures may sustain impact loads. Considering this phenomenon, this paper studied the dynamic properties of a carbon/epoxy 3D woven composite(3DWC). This will offer some reference to the practical applications and theoretical studies of that material.In this paper, experiments and finite element method are combined to study the strain rate effect and ballistic impact response of this 3DWC. The following work is completed.(1) The ballistic impact experiment is finished using the gas gun device. The impact response of the plate is studied. The failure mode of the plate and the velocity of the projectile is observed. The strain and displacement of the whole plate during impact is observed using digital image correlation(DIC) method. The experiment is simulated using finite element method, and the deformation of the plate is analyzed. The ballistic limit velocity is estimated through an energy method based on different simulation results.(2) Strain rate related experiments are finished using split Hopkinson bar. The deformation and damage of the specimen is observed. The mechanical properties of this 3DWC under different strain rate are investigated. The results indicated that the tensile properties and the compression properties have shown some regularities under different strain rate.(3) A finite element model of the split Hopkinson pressure bar is established, and the dynamic compression experiment is simulated. The stress-strain curve under different strain rate is obtained from the simulation. The results are basically consistent with the experimental results. The compression properties under higher strain rate is predicted.