Adiabatic shearing failure of explosively driven metallic cylinder shell, from experiments to simulation

Abstract

Abstract. The adiabatic shear bands (ASB) of the tubular metal specimens expanded explosively have been studied by many researchers in the recent years. The onset and evolutions of the multiple shear failure of metal cylinder under explosive loadings are affected by many factors such as the characteristics of the impulsive loadings, the dynamic behavior of the materials, etc. In this work, we investigate the failure and fragmentation of 45# steel cylinder shell driven by the JOB9003 explosive. Experimental and FEM numerical simulation investigations are made for cylinder modeled shell. The results show that for the perfect homogeneous FEM model, the failure mechanism of cylinder shell is differs from that of the experiments, in which the spalling originates is oriented by high intensity of rarefaction wave. Through numerical experiments, it was found that distributed geometrical defects of cylinder shell affect the fragmentation process and mechanism, in which the strain localization controlled by the defects and shear bands initiate on the inter-surface of the cylinder shell.

The effect law of shell surface crack propagation under implosion loading

“…Furthermore, the average axial propagation velocity of cracks on the shell surface is between 6000 and 9000 m/s, which is greater than the Rayleigh wave velocity (approximately 2000-5000 m/s), which is the ultimate propagation velocity of a single crack in metallic materials [30,31]. The rule may be proven in a series of hypervelocity photographic experiments for implosion cylindrical shell expansion fracture transients [32,33].…”