Systematic Study of the Failure Wave Phenomenon in Brittle Materials

摘要

Shock-wave experiments with four glasses of different hardness, two ceramics, quartz and silicon single crystals have been carried out with the goals to better understand in which materials the failure wave may occur under shock compression, which material properties control the formation and propagation, and what are the threshold conditions. Experiments with piles of thin sample plates confirm the appearance of the failure wave in elastically compressed fused quartz, K8 crown glass, and heavy flint glass, although the relationships between the Hugoniot elastic limits and the failure thresholds of these glasses are different. For softest heavy flint glass, the failure threshold is closest to the HEL. The failure waves were not recorded in single crystals and polycrystalline alumina and boron carbide ceramics. The results show that the propagation speed of the failure wave in glass slightly depends on the stress above the failure threshold, and does not depend on the propagation distance. The process becomes unstable and stops at stresses near the failure threshold. Longitudinal compressibility of comminuted glass has been found close to that of intact material. Preliminary results of computer simulations demonstrate the potential of the combustion-like model in simulating the evolution of failure wave.