FEM analysis of metal flowing behaviors in porthole die extrusion based on the mesh reconstruction technology of the welding process

Abstract

A reconstruction technology of finite element meshes based on reversal engineering was applied to solve mesh penetration and separation in the finite element simulation for the divergent extrusion. The 3D numerical simulation of the divergent extrusion process including the welding stage for complicated hollow sections was conducted. Based on the analysis of flowing behaviors, the flowing velocities of the alloy in portholes and near the welding planes were properly controlled through optimizing the expansion angle as well as porthole areas and positions. After the die structure optimization, defects such as warp, wrist, and the wavelike are eliminated, which improves the section-forming quality. Meanwhile, the temperature distribution in the cross section is uniform. Especially, the temperature of the C-shape notch with a larger thickness is lower than that of other regions in the cross section, which is beneficial for balancing the alloy flowing velocity.

Keywords

numerical simulation / extrusion / metal forming / metal flow / reconstruction

References

[1] Xie J.X., Liu J.A. Theory and Technology of Metal Extrusion, 2001 Beijing, Metallurgical Industry Press, 33.

[2] Murakami S. Adoption of aluminum extrusion and its technology. J. Jpn. Soc. Technol. Plast., 2008, 567(49): 25.

[3] Di L.Q., Zhang S.H. Porthole die extrusion process numerical simulation and optimal die design. J. Plast. Eng., 2009, 16(2): 123.

[4] Jo H.H., Lee S.K., Jung C.S., Kim B.M. A non-steady state FE analysis of Al tubes hot extrusion by a porthole die. J. Mater. Process. Technol., 2006, 173(2): 223.

[5] Jo H.H., Lee S.K., Lee S.B., Kim B.M. Prediction of welding pressure in the non-steady state porthole die extrusion of Al7003 tubes. Int. J. Mach. Tools Manuf., 2002, 42(6): 753.

[6] Jung M.L., Byung M.K., Chung G.K. Effects of chamber shapes of porthole die on elastic deformation and extrusion process in condenser tube extrusion. Mater. Des., 2005, 26(4): 327.

[7] Liu G., Zhou J., Duszczyk J. FEM analysis of metal flow and weld seam formation in a porthole die during the extrusion of a magnesium alloy into a square tube and the effect of ram speed on weld strength. J. Mater. Process. Technol., 2008, 200(1–3): 185.

[8] Yang D.Y., Park K., Kang Y.S. Integrated finite element simulation for the hot extrusion of complicated Al alloy profile. J. Mater. Process. Technol., 2001, 111(1–3): 25.

[9] Donati L., Tomesani L. The prediction of seam welds quality in aluminum extrusion. J. Mater. Process. Technol., 2004, 153(10): 366.

[10] Yang D.Y., Kim K.J. Design of processes and products through simulation of three-dimensional extrusion. J. Mater. Process. Technol., 2007, 191(1–3): 2.

[11] Li L., Zhang H., Zhou J., et al. Numerical and experimental study on the extrusion through a porthole die to produce a hollow magnesium profile with longitudinal weld seams. Mater. Des., 2008, 29(6): 1190.

[12] Wu X.H., Zhao G.Q., Luan Y.G., Ma X.W. Numerical simulation and die structure optimization of an aluminum rectangular hollow pipe extrusion process. Mater. Sci. Eng. A, 2006, 435(5): 266.

[13] J.X. Xie, D.N. Huang, J.Y. Li, and Z.H. Zhang, A Method for Simulating Welding Process of Hollow Profile Extrusion with Porthole Die, Chinese Patent, CN101604350A, 2009-12-16.

[14] Huang D.N., Li J.Y., Zhang Z.H., Xie J.X. The metal flowing behaviors during the diplopore extrusion of square tube by a porthole die. Trans. Nonferrous Met. Soc. China, 2010, 20(3): 488.

[15] Chanda T., Zhou J., Kowalski L., Duszczyk J. 3D FEM simulation of the thermal events during AA6061 aluminum extrusion. Scripta Mater., 1999, 41(2): 195.