Shock induced void nucleation during Taylor impact

Taylor impact experiments in the classic and symmetric configurations were used to study the plastic deformation and void nucleation in Al-6082-T6 rods. Deformation histories during impact were recorded using high-speed photography. X-ray computed tomography was used to visualize the extent of damage in recovered specimens. Above threshold velocities, void nucleation was observed along the central axis of the specimens, and reconstructed images from the tomography provide a 3-D mapping of the damaged region. The use of X-ray tomography is the first step in developing a method to characterise the damage process during impact using in-situ flash X-rays, which is also attempted in this study. Finite element simulations of these experiments are in good agreement with the experimental measurements, and confirm that void nucleation is due to the coalescence of lateral release waves at the centre of the specimen. The simulations also revealed that the time to failure is velocity dependent, and that the threshold velocity for void nucleation is sensitive to the properties and geometry of the target.