Analysis of the inclination angle and thickness of the armor plate of the bullet resistant on the aluminum and stainless steel plates by finite element method

Abstract

This thesis was an analysis of the significance of angle of inclination and the thickness of the armor plate on the penetration resistance of bullets on aluminum and stainless steel armor plates, determined by the finite element method. In this study, the information results obtained from actual firing of bulletproof armor and the finite element simulation according to NIJ 3 standards were compared to create a pattern of bulletproof and bulletproof armor using the SolidWorks program. The simulation model of the armor shooting was created by the Ansys/Explicit Dynamics program. The bullet material was 7.62 mm tungsten carbide (WC). There were three plate types used in the simulation were made of different bulletproof armor materials: 1) stainless steel SUS304 using for the plate thickness of 5, 6, 8, 10, 14, 20, 30, 40, 45, and 55 mm. 2) aluminum AL7075 using for the plate thicknesses of 6, 8, 10, and 20 mm. Additionally, 3) tungsten carbide using for the plate thicknesses of 6, 8, and 10 mm. Each of these plates had a width x length of 300 x 300 mm. The simulation models were divided into two types: Type 1, a simulation firing at one plate at a time. Type II, a simulation firing at two layered plates stacked together without any gaps between plates. The front and the back plates, made of stainless steel and aluminum, respectively, or tungsten carbide and stainless steel, respectively, were determined. The angles of firing at bulletproof armor were set at 0, 30, and 45 degrees. The output results were that in Type I, the stainless-steel plate with a thickness of 30 mm or more could resist the penetration of bullets. However, in Type II, 2 stacked layers of the armor plates using the front stainless plate with a thickness of only 20 mm and the back aluminum plate with a thickness of only 8 mm could provide the same constructive results as those of tungsten carbide and stainless steel plates for the front and back plates, with both thickness setting at 16 mm. All of them showed the resistance of the penetration to the bullets. More observation was that the increases in angles, as a result, enhanced more resistance of the bulletproof plates to bullet penetration.