Ballistic Impact Simulation of Proposed Bullet Proof Vest Made of TWIP Steel, Water and Polymer Sandwich Composite Using FE-SPH Coupled Technique

The bullet-resistant vest (bullet proof vest) is an important accessory to absorb impact energy and stop bullets from penetrating the body. In the present work a sandwich composite structure was designed from different sequential layers of, twinning induced plastic (TWIP) steel, polypropylene – polyethylene (PP-PE) polymer and water for bullet proof vest application. Owing to the difficulty in experimentally testing materials for ballistic impact application, a finite element – smoothed particle hydrodynamic (FE-SPH) coupled simulation was applied for analyzing the impact characteristics of the proposed composite structure. Different structural layers of the composite are simulated to select the most effective thickness of steel/polymer/water layers in energy absorption and penetration prevention. The simulation results displayed that the optimum thickness of the layers are 2 mm steel/20 mm water/2 mm steel , which is able to stop a 9 mm bullet travelling at 360 m/s with less than 10 mm displacement of the inner surface of the composite. This composite is promising and has a great potential in fabrication of effective and light weight bullet proof vest with less expensive materials.