Microstructure Evolution and Constitutive Analysis of Al-Mg-Si-Ce-B Alloy during Hot Deformation

In the present work, hot compression tests of Al-Mg-Si-Ce-B alloy were carried out with temperature of 623-823 K and strain rates of 0.01-50 s(-1), using a Gleeble 3500 thermal simulation tester. The microstructure evolution of the alloy was investigated by transmission electron microscopy and electron backscattered diffraction. From the true stress-strain curves, work hardening is evident at the beginning of hot compression. Dynamic recovery (DRV) and continuous dynamic recrystallization occurred, and DRV is confirmed to be the main softening mechanism. It is revealed that both the peak and steady values of the true stress decrease with increasing temperature and decreasing strain rate, which implies an increase in the degree of dynamic softening. Physical-based diffusion models and a bio-functional artificial neural network (ANN) model were constructed to predict the hot deformation behavior, of which the accuracy was evaluated based on the average relative error and the correlation coefficient (R). The ANN model was found to have the highest accuracy.