An improved model of damage depth of shock-melted metal in microspall under triangular wave loading*

Abstract

Damage depth is an important dynamic parameter for describing the degree of material damage and is also a key fundamental issue in the field of impact compression technology. The present work is dedicated to the damage depth of shock-melted metal in microspall under triangular wave loading, and an improved model of damage depth considering the material’s compressibility and relative movement is proposed. The damage depth obtained from the proposed model is in good agreement with the laser-driven shock loading experiment. Compared with the previous model, the proposed model can predict the damage depth of shock-melted metal in microspall more accurately. Furthermore, two-groups of the smoothed particle hydrodynamics (SPH) simulations are carried out to investigate the effects of peak stress and decay length of the incident triangular wave on the damage depth, respectively. As the decay length increases, the damage depth increases linearly. As the peak stress increases, the damage depth increases nonlinearly, and the increase in damage depth gradually slows down. The results of the SPH simulations adequately reproduce the results of the proposed model in terms of the damage depth. Finally, it is found that the threshold stress criterion can reflect the macroscopic characteristics of microspall of melted metal.