Effect of Process Parameters on Instability and Drawing Accuracy in Aluminum Rectangular Tube Drawing Process

摘要

The finite element model for aluminum rectangular tube drawing process has been established to investigate the metal flow instability and make further analysis on the forming defects based on the original drawing process scheme, such as the concave on tube side, warping, uneven wall thickness and "ear" appeared at the end of drawn tube. The original transition profile has then been redesigned and the influence of main process parameters, i.e., the die semi-angle a, the length of sizing zoon L, the friction coefficient Μ; the drawing velocity v; the transition arc radius in the junction of deformation zoon and sizing zoon R, on tube drawing accuracy has been discussed by integrating the orthogonal experimental design and numerical simulation. The transition section has been determined as the approximate rectangular and the optimal combination of process parameters (v=12.5 mm/s, L=9 mm, μ=0.05, R=5 mm, α=9°) has been obtained. The aluminum rectangular tube drawing process after optimization has been simulated by FEM and validated by the experimentation simultaneously. Both results confirm the effectiveness of drawing process optimization. The research achievements will be greatly helpful for improving the drawing accuracy of aluminum rectangular tube in practical production.