A comparative study of finite element analysis of single-particle impact on mild steel with and without strain rate considered

Abstract

Many materials are strain rate sensitive. It is therefore the purpose of this study to conduct a comparative study of single-particle impact on mild steel with and without strain rate considered using Finite Element Analysis (FEA). The Cowper-Symonds material model was used to define the target material. The parameters influencing the strain rate in the material model were determined based on experimental data. We built two types of FE models, which are the FE model of type I with the particle in a lower impact velocity and a smaller size as well as the FE models of type IIi (i=1, 2) with the particles in higher impact velocities and larger sizes. The simulation results show that the craters on the target material without strain rate considered are larger than those with strain rate considered in both FE models, which is because that for the target material with strain rate considered, the yield stress of the target material is increased due to an instantaneous impact of the particle, restraining its further deformation. It is interesting that for the FE models of type II2, the morphologies of simulation craters with strain rate considered and without strain rate considered are similar to those of experimental craters on the annealed copper and work-hardened copper, respectively. Under an oblique impact angle, an elongated lip is created at the end of the crater without strain rate considered, whereas no such lip is created on the target material with strain rate considered. This work provides a guideline for the investigation of the effect of strain rate on target material during erosion.