OBLIQUE PENETRATION OF AP PROJECTILE TO LAMINATED COMPOSITES-MODELING AND VERIFICATION

There are large amounts of research and publications concerning the modeling of ballistic impacts on various ballistic panels composed of composite materials. Most of these studies deal with normal (perpendicular) hits. Also, most of the theories which describe ballistic impact with composites of laminated fabric discuss perpendicular impact and how the kinetic energy of the projectile is absorbed by the panel. There are few studies of oblique impact and its penetration of laminates, yet most of them do not describe the penetration phase. Rosenberg et al. (2005) presented the concept of deflecting the projectile's course instead of absorbing the kinetic energy by relatively low strength and lightweight material such as PMMA, as discovered earlier by Yeshurun et al. (1998). As part of a research effort to optimize the structure of ballistic panels the Plasan Research Department investigated the interaction between Armor Piercing (AP) 0.3 (M61) and oblique laminated ballistic plates made of UHMWPE (Dyneema (R)). The motivation was to use very light material to change the projectile's course instead of absorbing the kinetic energy. The ballistic efficiency was compared to normal penetration. In this paper the model, which was developed using LSDYNA code, will be presented, as well as the predictions and results of verification tests which were performed in the Plasan Ballistics Laboratory. Very good correlation was observed, both qualitatively and quantitatively, between the model prediction and the experimental deflection phenomena. The use of extremely light ballistic panels made of laminas for changing the AP round trajectory was here proved experimentally.