CIRCUITRY , STRUCTURE AND PROPERTIES OF HETEROGENEOUS MATERIALS

Currently, heterogeneous materials based on titanium and aluminum alloys are widely used as promising armor materials. When a ballistic object is exposed to the armor material, brittle cracks that occur at the contact point spread in such a way that composite material is in state of decay both deep into and along the interlayer boundaries of the joint, while there is a violation of the composite structure and loss of the mechanical strength of the armor element. In this regard, the task of developing new reinforcement schemes for composite armor is urgent. One of the most promising technologies in the field of creating and developing new composite non-metallic armor materials is explosion bonding. The authors of the work proposed a new scheme for reinforcing a heterogeneous metal material by means of explosion bonding, which uses internal perforated reinforcing layers that serve as elements preventing the development of brittle fracture at the point of ballistic contact. To increase the efficiency of the destruction of a ballistic object in the composite structure, the authors proposed the formation of highly solid intermetallic compounds at the boundary between the metal of the base of a viscous metal matrix and the reinforcing element by subsequent heat treatment of the material. The conducted micro-X-ray spectral analysis of intermetallic compounds showed their correspondence to the chemical compound α-titanium (TiAl3). Comparison of the obtained level of physical and mechanical properties of the developed heterogeneous armored material with analogues suggests that the expected level of the composite protection class against small arms is in the range from Br4 to Br5 according to GOST R 50963-96 with an armor thickness of 40 to 60 mm, which makes it possible to reduce the weight of armored vehicles significantly and, as a result, increase its tactical and technical characteristics.

Modeling and Simulation of Ballistic Penetration of Ceramic-Polymer-Metal Layered Systems

Numerical simulations and analysis of ballistic impact and penetration by tungsten alloy rods into composite targets consisting of layers of aluminum nitride ceramic tile(s), polymer laminae, and aluminum backing are conducted over a range of impact velocities on the order of 1.0 to 1.2 km/s. Computational results for ballistic efficiency are compared with experimental data from the literature. Simulations and experiments both demonstrate a trend of decreasing ballistic efficiency with increasing impact velocity. Predicted absolute residual penetration depths often exceed corresponding experimental values. The closest agreement between model and experiment is obtained when polymer interfaces are not explicitly represented in the numerical calculations, suggesting that the current model representation of such interfaces may be overly compliant. The present results emphasize the importance of proper resolution of geometry and constitutive properties of thin layers and interfaces between structural constituents for accurate numerical evaluation of performance of modern composite protection systems.