Effect of deformation routes on torsion behavior via ACDR process

Plastic flow in continuous incremental bulk metal forming had aroused great interest. However, due to the observational difficulties of each section, the torsion-state plastic flow behavior during axial closed die rolling (ACDR) is usually ignored. Therefore, the flow line in main plastic deformation zone (PDZ) was chosen for detailed investigation in order to unveil the effect of deformation routes on the weight of the circumferential torsion during ACDR process. Then, the modified equation of the equivalent von Mises strain of ACDR process is provided to illustrate the local plastic flow behavior under different deformation routes and different conditions of stress. The results show that the overall strength of PDZ does not significantly change with the loading history, but local plastic flow is enhanced with the increasing deformation time. Severe deformation accumulation in PDZ brings about the increasing radial tension and weakened circumferential torsion axial compression.