Improvement of the mechanical characteristics of impact-resistant and ultrahightemperature boride- and carbide-based ceramic composites and developing an algorithm for computer simulation of the conditions of penetration of armor protection structural elements from these materials

Improvement of mechanical characteristics (up to reaching whatever high values) of impact-resistant and ultrahightemperature ceramic composites based on borides and carbides prepared from mixtures of B4C-SiC, AlB12-TiC, HfB2-SiC, HfC-MoSi2 ZrB2-SiC, ZrB2-SiC-ZrC have been achieved due to sintering under high (4.1 GPa) and moderate (30 MPa) pressures and the formation of solid solutions. The interdiffusion of elements in the composites was demonstrated by EDX and quantitative Auger spectroscopy even in cases where Rietveld refinement of X-ray diffraction patterns did not provide an opportunity to clearly understand whether such interactions are taking place.
An algorithm for computer modeling of the conditions of penetration of structural elements of armor protection from developed impact-resistant composites was developed, taking into consideration their mechanical characteristics. The modeling algorithm had standard components of the numerical solution of solid mechanics problems and provided for the construction of geometric models of objects, their discretization into finite elements of the appropriate shape and size, determination of mechanical characteristics of materials, boundary conditions, selection of models of deformation and destruction of materials. To describe the deformation of plastic materials, the model of isotropic plastic material with kinematic strengthening (Johnson-Cook Strength) was used, for low-plastic ceramic materials, the Johnson-Holmquist Strength Segmented JH-2 model was used.
The computer simulation consisted of two parts. The first is a comparison of the results of test calculations with the experiment, and the second is the determination of the impact of various design solutions on the load-bearing capacity of armor protection elements. The main indicators of the effectiveness of protection were the change in the speed of the bullet in the process of penetration and the size of the destroyed part of the package.