A numerical study on the wave propagation in tensile and perforation test

Abstract
In this paper a numerical analysis of the effect of the initial velocities on the elastic and plastic wave propagation in tension and perforation of thin steel sheets is reported. The purpose was to analyze the maximum impact velocity above which the process of plastic deformation is disturbed by propagation of plastic waves and the appearance of the thermoviscoplastic instability. The limit is found and analyzed by the analytical and numerical methods in the form of so called the Critical Impact Velocity. A new approach to the CIV which takes into account the temperature coupling with plastic deformation is proposed. A precise constitutive relation which takes into account strain hardening, rate and temperature sensitivity is developed. This relation has been introduced to the FE code ABAQUS^TM. The FE analysis has been applied to the dynamic tension and perforation of the sheet steel ES. Existence of the CIV in tension has been confirmed numerically. The numerical results confirm also experimental findings in the case of perforation.