Nacre-like Aluminium Alloy Composite Plates for Ballistic Impact Applications

Abstract

It is a major scientific challenge to develop the light-weight materials with high performance simultaneously in diverse applications ranging from civil engineering to defence. Numerical results for composite plates of 5.4-mm, 7.5-mm and 9.6-mm thick bioinspired composite plates were compared with corresponding bulk plates under the impact of a rigid hemi-spherical projectile at same impact velocities. The most significant improvement was recorded for the 5.4-mm thick nacre-like aluminium alloy composite plate, which was attributed to the larger area of plastic deformation due to the tablet arrangement. Experiments data were collected to validate the numerical simulation. It has been found that the nacre-like composites of different thickness had better ballistic behaviour than the bulk ones. The aim of this thesis is to give general background and research progress about natural nacre and the corresponding nacre-inspired artificial composites, to provide the basis for preparing the detailed experimental and numerical study on the ballistic performance of nacre-like aluminium alloy composites. My following ballistic experiments are to validate the numerical simulation results that the nacre-like composite plate has better ballistic performance at high velocity due to the tablets arrangement and plastic deformation. From previous simulation results, 5.4-mm nacre-like plate has shown a significant performance improvement compared with same thickness bulk plate owing to the hierarchical structure induced high energy absorptions. Hence, plate thickness and projectile velocity play a significant role on the performance improvement of the proposed nacre-like AA7075-T651 composites. Further experimental works are needed to assess other crucial parameters for modifying the mechanical behaviours of such bioinspired materials.