Influence Of Ceramic Ball/UHPC Panel On Antipenetration Performance Of Composite Armor

Today,the world’s main battle tank armor and human protective equipment are highly valued by all countries and have been vigorously developed.A new type of close-packed ceramic ball composite armor was designed and prepared in this paper in order to avoid the problem that the ceramic plate/back plate composite armor can’t resist multiple attacks because of its overall damage in one impact.The ceramic ball composite armor also has a good performance in deflecting projectile due to its own curved surface characteristics.A combination method of experiments and numerical simulations was used to study the penetration process and damage of the close-packed ceramic ball composite armor against the10 mm 30Cr Mn Si armor-piercing projectile.The effects of the diameter of ceramic balls,the number of layers of close-packed ceramic balls,the restraint effect,the location of the impact point,the multiple shots and the degree of close packing on the anti-penetration performance of the target plate were mainly discussed.The followings were studies in this paper:(1)Follow the design principles of composite armor to optimize the armor materials of each layer,ultra-high-performance concrete(UHPC)was used to encapsulate close-packed ceramic balls,close-packed ceramic ball composite armors were prepared successfully and then ballistic tests were conducted finally.By comparing and analyzing the effects of the damage mechanism,damage morphology,diameter of ceramic balls and the number of layers on the anti-penetration performance of the target layer,it is concluded that when the projectile diameter is 10 mm,the design of 10 mm diameter single-layer ceramic ball structure is more compact and reasonable than that of 20 mm and 15 mm.Single-layer ceramic ball close-packed structure with diameters of 20 mm and 15 mm are structurally weak links at the gap and need to be improved.when the diameter of ceramic balls is larger than the projectile diameter,the armor protection performance is significantly improved after strengthening the weak links of singlelayer structure with two-layer ceramic ball close-packed structure.The three-layer ceramic ball structure needs a better restraint effect to ensure that the ceramic ball can give full play to its ballistic performance.(2)The 3D finite element model(FEM)was established by ANSYS / LS-DYNA to study the penetration process of ceramic ball composite armor.The effectiveness of the numerical simulation method was verified by comparing the experimental and numerical simulation results.The velocity and acceleration curves of the projectile,the anti penetration process of the target plate,the damage of the fiberboard and the back plate and the energy consumption were analyzed.The ceramic ball itself has a unique curved surface structure that easily causes the deflection of the projectile.The deflection increases the action time and penetration path,reduces the penetration depth and improves the target’s protective performance.The ceramic balls are independent of each other,and the damage is concentrated,so as to avoid the damage of the whole ceramic panel caused by the crack growth under the impact load,and improve the target’s ability to resist multiple shots.UHPC-encapsulated ceramic balls play a very good role in restraining their displacement and splashing.The ceramic balls are more completely broken,which increases the energy consumption of ceramic ball abrasion and improves the protective performance of the target.(3)Numerical simulation(restart function)was used to analyze the influence of different impact points,multiple shots and the degree of close packing.It is concluded that the impact performance of the target on the ceramic ball is better than that of the ceramic ball gap.When the projectile penetrates the ceramic ball,the closer the impact point is to the center of the ceramic ball,the better the protection performance of the target.Projectile diameter is 10 mm,ceramic ball diameter is 20 mm and 10 mm.When the projectile penetrates the ceramic ball gap,the impact point falls on the three-ball gap and the target has better protection performance than the two-ball gap.The multilayer ceramic ball composite armor structure is designed scientifically and reasonably,and it can withstand 2 shots of the 1140m/s incident speed of10 mm 30Cr Mn Si armor-piercing projectile.Hex-pack structure can improve armor protection performance compared to checkerboard structure.With the decrease of ceramic ball diameter,the armor protection performance will be improved first and then decreased.