Bioinspired nacre-like steel-polyurea composite plate subjected to projectile impact

Natural marine biological structures have evolved over a long period of time, and their comprehensive performance has huge advantages over artificial materials. In order to improve the overall strength of the artificial structure, inspired by the layered structure of nacre, a nacre-like steel-polyurea composite plate was designed as a new impact-resistant structure. On this basis, the damage deformation of three different layered steel-polyurea composite plates with nacre-like structure under different projectile velocities was simulated. The damage failure morphology of nacre-like composite plates with different layered numbers was analyzed, and consequently, five failure toughening mechanisms of nacre-like composite plates were summarized. Then, the fitted ballistic performance curves were used to compare the ballistic performance of nacre-like composite plates with different delamination, and it was found that the composite plates could reduce the residual ballistic velocity by 24.58% and increase the ballistic limit by 27.86%, and the energy dissipation mechanism of the composite plates was explained by the energy release of steel and polyurea layers. Finally, the theoretical analysis reveals that the increase in the delamination number can effectively increase the equivalent modulus of the nacre-like composite plate, thus enhancing the penetration resistance of the composite plate. (c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).