The Influence of Hot Deformation on the Mechanical and Structural Properties of 42CrMo4 Steel

Abstract

The influence of elevated temperatures and strain rate on the mechanical and structural properties of steel 42CrMo4 were analysed experimentally in this paper. The experiments were based on uniaxial tension and compression tests at high temperatures between 700 °C and 1100 °C and strain rates in the range 0.0018–0.1 s−1. The influence of temperature and strain rate on yield stress, strain to fracture, hardness, structural changes, and fracture characteristics were analysed. The non-uniformity of deformations obtained at different values of the strain rate and temperature were also analysed. Analysis by scanning electron microscopy showed the ductile behaviour of the material. The degree of damage in the material caused by the presence of cavities increased with increasing deformation temperature. For all the presented deformation conditions, the formation of the fracture through the ductile fracture mechanism resulted from localized necking and the coalescence of microvoids. By increasing the deformation temperature and reducing the strain rate, the fracture behaviour of 42CrMo4 steel can be improved.