Determination of Johnson–Cook Constitutive Model Parameters by Optimization Method

The empirical Johnson-Cook constitutive model (JC) is often used for numerical calculations of the dynamic interaction of deformable solids. However, increasing impact velocity leads to difficulties in the choice of constants of the JC model. In this paper, we propose a method for selecting the JC model constants using an optimization algorithm based on Nesterov gradient descent. We numerically simulated the impact of a cylinder on a non-deformable target (the Taylor impact test). The behavior of copper OFHC (M1) cylinders was considered in the impact velocity range of 162–316 m/s. The solution quality functional was used to compare numerical results with experimental data. The selected JC model constants improved the agreement between numerical and experimental results by 2.8 times.