Influence of the annealing cooling rate on the microstructure evolution and deformation behaviours in the cold ring rolling of medium steel

Pre-heat treatment is a necessary step of cold ring rolling that leads to different microstructure evolution processes and different macroscopic deformation behaviours of rings in the cold ring rolling process. In this paper, the cold ring rolling process of 1045 steel with different annealing cooling rates is studied because the annealing cooling rate is the factor with the greatest influence on the result of the pre-heat treatment. By subjecting 1045 steel to different annealing cooling rates, it is found that, within the experimental range, the grain size of the rings becomes smaller and the lamellar spacing of pearlite decreases as the annealing cooling rate increases, resulting in a stronger and tougher material. The ABAQUS finite element (FE) software was employed to simulate the cold ring rolling process. The simulations indicated that increasing the annealing cooling rate causes the stress in the rolled rings to increase, the strain to decrease and the cementite lamellae to become more fractured.