Plastic Deformation Mechanism in Double-Roller Clamping Spinning of Flanged Thin-Walled Cylinder

Abstract

Double-roller clamping spinning (DRCS) is a new process for forming a thin-walled cylinder with a complex surface flange. The process requires a small spinning force, and can visibly improve forming quality and production efficiency. However, the deformation mechanism of the process has not been completely understood. Therefore, both a finite element numerical simulation and experimental research on the DRCS process are carried out. The results show that both radial force and axial force dominate the forming process of DRCS. The deformation area elongates along the radial direction and bends along the axial direction under the action of the two forces. Both the outer edge and round corner of the flange show the tangential tensile stress and radial compressive stress. The middle region shows tensile tangential stress and radial stress, while the inner edge shows compressive tangential stress and radial stress. Tangential tensile strain causes a wall thickness reduction in the outer edge and middle regions of the flange. The large compressive thickness strain causes material accumulation and thus, an increase in the wall thickness of the round corner. Because of bending deformation, the round corner shows a large radial tensile strain in addition. The inner edge of the flange shows small radial compressive strain and tensile strain in thickness. Thus, the wall thickness on the inner edge of the flange continues to increase, although the increment is small. Furthermore, microstructure analysis and tensile test results show that the flanged thin-walled cylinder formed by DRCS has good mechanical properties. The results provide instructions for the application of the DRCS process.