Finite Element Analysis of Ballistic Impact on Dissimilar Multi-Layered Metal Targets

Abstract

Impact problems have always been a field of interest for researchers. Practical problems involve large amount of heat generation due to plastic deformation. In this paper, we have studied monolithic and multi-layered target being impacted by rigid projectile using finite element method. Two different materials—1100-H14 aluminium and Weldox 700 E steel—are layered up as target. The influence of thickness of layer, number of layers, and temperature softening on the ballistic phenomena are studied using Finite Element Package ABAQUS/ Explicit. To include the thermal softening effect, the dynamic temperature displacement explicit model is used for the finite element analysis. The targets are modelled using Johnson–Cook material model and Johnson–Cook fracture model. Projectile shapes such as ogival and conical are used for comparison of ballistic resistance of each configuration. The analysis with monolithic target showed that the failure mechanism in both the cases—conical and ogival-shaped projectile—involved hole enlargement and petal formation. Multi-layered configuration of aluminium layer in front and steel layer at back showed more obstruction. For ogival projectile, the target failure involves ductile hole enlargement and petalling, whereas conical projectile caused target to fail by ductile hole enlargement and plugging. As the frontal portion of projectile changes from conical to blunter shape, failure mechanism transforms from petalling to plugging. It was observed that with decrease in impact velocity and decrease in number of layers, velocity drop increased. © 2016 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of Implast 2016. © 2016 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of Implast 2016.