Numerical simulation and die structure optimization of an aluminum rectangular hollow pipe extrusion process

Uniform material flow in the cross section of the bearing exit in an aluminum extrusion process is extremely important for getting high quality products. In general, several measures are taken to eliminate non-uniform material flow, such as adjustment of the size, shape and location of portholes and welding chamber, modifications of local bearing lengths, etc. In the present work, an aluminum profile porthole die extrusion process is simulated using the finite volume method based numerical analysis software Msc/SuperForge. The simulation results show that with the originally designed die the material flow velocities in the profile cross-section of the bearing exit are non-uniform. Aiming at solving this problem, three die structure modification schemes are proposed and their extrusion processes are simulated, respectively. The optimal die design scheme is determined by comparing the simulation results. For comparison, the same process is simulated with finite element based DEFORM 3D, and the results are similar with those obtained with SuperForge, but the accuracy is lower and much more computation time is needed due to frequent mesh regeneration.