A New Analysis of the Mechanics of Fixed-Plug Tube Drawing with Application on a Low Carbon Steel Tube

Knowledge of the deformations that occur during the plastic forming of metals and the necessary forces is of key importance in engineering. The Fixed-Plug Tube Drawing (FPTD) process permits reductions of the diameter and the wall thickness of a tube to the desired geometry. In this study, a new analysis of the mechanics of the FPTD process is presented. The analysis was inspired by finite element simulations of the process. It has been found that the second stage of the main deformation process within the die can be described by a simple shear deformation mode. Using this principle, the velocity gradient field and the stress state for the drawing force was determined, and a new formula, much simpler than the existing Geleji formula, was obtained. The new modeling was validated by comparing the simulated drawing force to the experimental one, showing slightly better agreement than the finite element simulations or the Geleji formula. The comparison of the measured and VPSC-simulated textures further validated the new analytical approach. It has been found that the textures obtained in FPTD are highly similar to the textures observed in cross-rolling low carbon steel. The similarity, however, was obtained between different pole figures, the reason for which is the difference in strain paths.