Validation of FE models of bullet impact on high strength steel armors

摘要

This paper presents a validation of a finite element (FE) model to predict the performance of high strength steel armor against the penetration from M193 bullets. A series of perforation tests were performed on an Armox 600T steel plate. The velocity of bullet was measured using an electronic measuring system. A propellant weight of the bullet was calibrated before the test so as to obtain a desired bullet velocity which meets the test standard. The test results show that only one shot from all tests penetrated a 7 mm of Armox 600T. Generally, a 7mm of Armox 600T is sufficient to withstand the threat level specified in the test standard. An Eulerian FE solver was employed to simulate behavior of a bullet impact. A series of FE analyses varying Eulerian cell sizes were performed in this study so as to obtain converge results. It is found that an element size of 0.035 mm is required for this type of modeling in order to capture a realistic interaction between bullet and armor plate. The FE results of the model with 0.035 mm of cell size conform to the test results in terms of crater depth and crater diameter on the test armors.