Comparison of Impact Damage between Ceramic Structure and Nacre-Like Ceramic/Polyurea Composite Structure

The finite element model of a ceramic beam impacted by a blunt-nosed projectile was established, and the impact damage evolution process of the beam was simulated. The simulation results are in good agreement with experimental results, which confirms the validity of the model. On this basis, the finite element model of a nacre-like ceramic/polyurea composite beam impact by the same projectile was established. Its damage evolution process was compared with that of the ceramic beam. Effects of impact velocity of projectile on damage process are studies for the two beams. The obtained results show that the damage of the ceramic beam expands conically, and the beam undergoes global damage. The damage of the nacre-like composite beam expands in a cylindrical shape in the longitudinal direction (i.e., impact direction), and the beam undergoes local damage, which gives a good ability to maintain structural integrity. Moreover, as the impact velocity of the projectile increases, the range and extent of damage of the ceramic beam increases significantly. Differently, when the impact velocity exceeds a certain value, the damage range of the nacre-like composite beam changes insignificantly, while its damage extent grows with the increase of impact velocity.