The thesis addresses the problem of simulating high-speed deformations that occur under impact loading of a material. In such conditions, the material undergoes a pronounced plastic response accompanied by complex mechanical and thermal phenomena. Classical (quasi-)static models are insufficient in these cases therefore, for reliable prediction of the response, it is necessary to use advanced constitutive models that account for the effects of strain rate and temperature. At the beginning of the thesis, the theoretical foundations of high-speed deformations and the material models available in Abaqus are presented. In the experimental part, we compared the Johnson–Cook hardening model with the Isotropic model, using as a case study the impact of a sphere on a metal sheet. The two material models were compared in terms of the amount of plastic deformation, the computation time, the temperature reached in the bodies, and the visual appearance of the final simulation state. We found that using the Isotropic model results in a shorter solution time. Furthermore, we concluded that the simulation results depend less on the chosen constitutive model than on the appropriate input material parameters used to describe the material’s behavior.
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