Experimental investigation of the dynamic fragmentation process in a transparent ceramic under impact loading

Abstract

In the present project, edge-on impact (EOI) experiments have been conducted to improve the understanding and modelling of the dynamic fragmentation process in a transparent ceramic. In the EOI experiments a cylindrical projectile hits the edge of the target with an impact velocity ranging from 60 to 175 m/s. An ultra-high speed camera is used to visualize the fragmentation process with an interframe time set to 1 μs. An intense and complex cracking network develops in a ten of μs into the target composed of numerous “radial cracks”, “Rayleigh cracks” and “release cracks”. The intensity of damage increases with the impact velocity. In addition, numerical simulations of impact tests have been conducted considering the DFH (Denoual-Forquin-Hild) anisotropic damage model. Finally the numerical predictions of DFH model are compared to the experimental results in terms of cracking density and velocity of damage front.