Hot deformation and processing map of Cr-Mo-B mechanical engineering steel

Abstract

The hot deformation behavior of Cr-Mo-B mechanical engineering steel was conducted at deformation temperature of 850-1150℃ and strain rates of 0.1-10s-1. The artificial neural network(ANN) model was developed based on the true stress-strain curves, where the input parameters were deformation temperature, strain rate, strain, and flow stress was the output parameter. The results show that the ANN model is accurate in predicting the flow stress, and the root mean square error is 1.3858. Based on the dynamic material model (DMM), the processing maps of the studied alloy at true strains of 0.5 and 0.7 are constructed to recognize optimum hot deformation regions:the optimum region for the strain of 0.5 is at deformation temperature of 1050-1150℃ and strain rate of 0.1-0.4s-1 with a peak power dissipation factor of about 37.20%, and the optimum region for the strain of 0.7 is at deformation temperature of 1000-1150℃ and strain rate of 0.1-0.6s-1 with a peak power dissipation factor of about 35.80%.

Keywords

• mechanical engineering steel
• constitutive model
• neural network
• processing map