Jason K. Lee

Date of Award


Document Type


Degree Name

Master of Science in Aeronautical Engineering


Department of Aeronautics and Astronautics

First Advisor

Anthony N. Palazotto, PhD


Multi-layer armor containing ceramic and metallic layers has become more common in the past two decades. Typically, ceramics have high compressive strength which combined with their low density make them highly desirable for armor applications. This research effort numerically simulates high velocity impact of cylindrical projectiles on multi-layer metallic and ceramic targets of finite thickness. The impact of the projectile occurs normal to the surface of the target. The projectiles used are made of either S7 tool steel or tungsten. The targets consist of either rolled homogeneous armor, 4340 steel and boron carbide ceramic or rolled homogeneous armor and boron carbide ceramic. The Eulerian hydrocode CTH, ideal for studying cases of gross global and local deformation, is used to perform an axisymmetric analysis of the projectile and the target. The Johnson-Holmquist constitutive model (JH-2) for brittle materials is used for the ceramic layers, and the Johnson-Cook constitutive model is used for the metallic layers. Various arrangements of ceramic and metallic layers were simulated over a range of velocities to quantitatively determine ballistic limits. Comparison of the ballistic limits for each configuration will determine which ceramic-metal lay-up arrangement is optimal for resisting penetration of the given projectile. A variety of options in CTH are taken into account in this research. This research shows that replacing multiple metallic target layers with B4C ceramic decreases the resistance of the target to the penetration of the projectile for a target of given thickness.

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