Constitutive Modelling Analysis and Hot Deformation Process of AISI 8822H Steel

This study used the Gleeble 3800 thermomechanical simulator to examine the hot deformation characteristics of AISI 8822H steel. The main goal was to understand the alloy's behaviour under various thermomechanical settings, emphasising temperature ranges between 1173 K and 1323 K and strain rates from 0.01 s^-1 to 10 s^-1. This study aimed to enhance the alloy's manufacturing process by offering a thorough understanding of the material's response to these conditions. Four various constitutive models-Arrhenius-type, Johnson-Cook, modified Johnson-Cook, and Trimble-were used in a comprehensive technique to forecast flow stress values in order to meet the study's goals. The accuracy of each model in forecasting the behaviour of the material under the given circumstances was assessed. A thorough comparison investigation revealed that the Trimble model was the most accurate model allowing prediction of material behaviour, with the maximum correlation factor (R = 0.99) and at least average absolute relative error (1.7%). On the other hand, the Johnson-Cook model had the least correlation factor (R = 0.92) and the maximum average absolute relative error (32.2%), indicating that it was the least accurate because it could not account for all softening effects.