International Journal for Research in Applied Science & Engineering Technology (IJRASET)

ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor: 7.538

Volume 11 Issue III Mar 2023- Available at www.ijraset.com

Most of the impact energy would be absorbed and dissipated during the process while the rest is retained in the impactor as rebound kinetic energy [52]. Afterimpact, an undetectable or barely detectable by visual inspection residual plastic indentation may be left ontop face-sheet of the sandwich panel. Indentation characteristics and energy absorption property are basically determined by crashworthiness of the structure, which is extremely sensitive to the mechanical property of matrix material [53]

ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor: 7.538

Volume 11 Issue III Mar 2023- Available at www.ijraset.com

The impact behaviour of the target was also examined by investigating the energy absorption characteristics of the targetplate subjected to projectile impact. Iqbal et al. [19] and Tiwarietal. [20] reported the experimental and numerical studyon the energy dissipation character of the thin plates and shellsof Al 1100-H12 aluminium and concluded that the maximum energy of the projectile dissipated in tangential stretching of the target.

II. OBJECTIVE

This research aims to optimize the construction of structure byhybridization in order to achieve the improvement of ballistic performance and reduction in weight. To achieve this aim, the research objectives are organized as follows.

1) Understanding the ballistic response of structures under impact. This includes different ballistic characteristics, energy absorption, as well as failure modes under ballistic impact.

a) Different ballistic characteristics of each layer will be analyses experimentally and numerically, such as ballistic resistance fracture time, transverse deflection, stress distribution, energy absorption and ballistic limit. This investigation will reflect the different ballistic resistant efficiency of each layer in the panel, through which the mechanisms of energy absorption can be identified.

b) Failure modes are important aspects to reflect ballisticresponse under impact. It will be systematically investigatedthrough the photographic observations of post-impact panelslayer by layer. This work will provide a wealth of physical evidences to reflect different ballistic characteristics of eachlayer.

2) Optimization of the ballistic structure design. Theconstruction of the structures will be optimized by combining different components of ballistic materials in the most effective positions. To design the hybrid structure, the mechanisms of hybridization will be analyzed and identified before the design principleis put forward.

a) Selection of components for hybridization will be studied. In this research, Metallic materials, composites as well as fibers are studied and will be used as components for hybridization. Ballistic performance of these structures will be investigated on their advantages and disadvantages for ballistic protection.

b) The hybridization effect will be investigated by analyzing the ballistic performance of hybrid structures and hybrid materials. Layering sequences of different components will be explored to determine the better combination manner of materials

3) This study will be carried out using two research approaches, namely the experimental method and the Finite Element (FE) analysis. The experimental studies will be centered on ballistic tests andphotographic observations of post impact panels. FE numerical simulation will be used to explore the ballistic response of the structure. These data then helps to find out ballistic resistance, ballistic limit, failure modes and the energy absorption characteristic of structures against different projectile nose shape.

4) Effect of cell wall thickness. Cell wall thickness plays a significant role in enhancing the impact resistance of the sandwich structure. Cell wall thickness 0.03 mm, 0.05 mm, 0.07 mm and 0.09 mm were used to find out its effect on the ballistic performance of the hemispherical sandwich shell structure. Similar to the face sheet thickness, the velocity drop increased with increase in the cell wall thickness, see it was found that with the increase in the cell wall thickness, the ballistic limit of the panel increased.