High‐Temperature Deformation and Flow Stress Model of 4Cr13 Continuous Casting Billet at Low Strain Rates

The high‐temperature mechanical properties of steel play a crucial role in the design of continuous casting and straightening process parameters. In this study, high‐temperature compression tests were conducted on 4Cr13 continuous casting billet samples using the Gleeble‐3800 thermal simulation machine, obtaining the true stress–strain curves of 4Cr13 continuous casting billets at strain rates of 0.001, 0.005, and 0.01 s −1 and compressive deformation temperatures of 750, 800, 850, and 900 °C. Based on the obtained true stress–strain curves, the Arrhenius strain‐compensated model, the modified Johnson–Cook model, and the modified Zerilli–Armstrong model were respectively established to predict the high‐temperature flow behavior of the 4Cr13 continuous casting billet. The average absolute relative errors (AARE) of the three models are 7.420%, 7.623%, and 9.521%, respectively. Under the experimental conditions of this study, both the Arrhenius strain‐compensated model and the modified Johnson–Cook model show good predictive capability for the true stress of the 4Cr13 continuous casting billet. The overall prediction accuracy of the former is slightly better than that of the latter. However, the modified Johnson–Cook model is more practical for engineering applications due to its computational simplicity. In contrast, the modified Zerilli–Armstrong model exhibits poorer prediction accuracy for this steel grade.