Study of the shock-wave compressibility of heterogeneous anisotropic materials

Abstract

Investigation of shock-wave compressibility of three anisotropic materials (carbon fibre reinforced plastic, textolite and kevlar) was performed by a VISAR laser interferometer. Two of these composites consist of the same aramid fibers (textolite and kevlar) and two of them have the same structure (CFRP and kevlar). The structure of compression pulse and shock wave velocity of materials were obtained in each experiment. The shock wave structure in tested composites significantly depends on the fibers orientation - a two-wave configuration is recorded in almost the entire range of studied pressures when shock wave propagates along the fibers. Hugoniot parameters of anisotropic materials were obtained in the coordinates of the shock wave velocity D – particle velocity u for two orientations of the fibers. Hugoniots of kevlar, textolite and CFRP with perpendicular orientation of the fibers are parallel to each other. For kevlar and CFRP, the shock wave compressibility almost does not depend on the fibers orientation relative to the direction of the shock wave propagation. In textolite with parallel orientation of the fibers, the shock compressibility is determined by the properties of unidirectional aramid fibers, and Hugoniots for two directions differ significantly.