A meshfree study of the Kalthoff–Winkler experiment in 3D at room and low temperatures under dynamic loading using viscoplastic modelling

A new model for studying the fracturing of metals under impact using Smoothed Particle Hydrodynamics is presented. The model combines a temperature and strain rate dependent flow stress with a criterion for brittle fracture and is suitable for metallic materials undergoing high strain rate loadings. First, the well documented Kalthoff–Winkler experiment was used to validate our approach. A series of simulations was then conducted to model the behaviour of a 4340 steel at 223 K (−50 °C) under different impact speeds to investigate the simultaneous effect of temperature and impact velocity towards the failure of the material. In some cases a lower temperature brought about failure for the same impact velocity, highlighting the role of combining factors in failure analysis. This paper demonstrates the relevance of SPH in the prediction of the initiation and propagation of brittle cracks in structures, thus opening new areas for future research.