Comparative Numerical Analysis of Sheet Formed into a V-Shaped Die Using Conventional and Electromagnetic Forming Processes

A comparative and numerical study on the formability of a sheet formed into a V-shaped die using a conventional stamping operation and an electromagnetic forming (EMF) process was performed. To evaluate the damage evolution and failure prediction using a finite-element method (FEM), the Gurson-Tvergaard-Needleman plasticity material model was employed in the numerical simulation. The impact of the sheet with the die generates a complex stress state during the EMF process. Damage suppression due to the tool-sheet interaction may be one of the main factors contributing to the increased formability in the EMF process compared to the conventional forming operation. In addition, a high level of kinetic energy produces high strain-rate constitutive and inertial effects, which delay the onset of necking and may also be responsible for the increased formability using EMF.

[1]  J. H. Jiang,et al.  Application of electromagnetic-assisted stamping (EMAS) technique in incremental sheet metal forming , 2006 .

[2]  Michael J. Worswick,et al.  Reduction of a pre-formed radius in aluminium sheet using electromagnetic and conventional forming , 2012 .

[3]  A. Needleman,et al.  Analysis of the cup-cone fracture in a round tensile bar , 1984 .

[4]  Sergey Fedorovich Golovashchenko,et al.  Formability and Damage in Electromagnetically Formed AA5754 and AA6111 , 2004 .

[5]  Li Fuguo,et al.  Forming Limit Stress Diagram Prediction of Aluminum Alloy 5052 Based on GTN Model Parameters Determined by In Situ Tensile Test , 2011 .

[6]  Glenn S. Daehn,et al.  Electromagnetically assisted sheet metal stamping , 2011 .

[7]  A. Tekkaya,et al.  Electromagnetic forming—A review , 2011 .

[8]  Glenn S. Daehn,et al.  Increased ductility in high velocity electromagnetic ring expansion , 1996 .

[9]  A. Gurson.  Continuum Theory of Ductile Rupture by Void Nucleation and Growth: Part I—Yield Criteria and Flow Rules for Porous Ductile Media , 1977 .

[10]  D. M. Tracey,et al.  On the ductile enlargement of voids in triaxial stress fields , 1969 .

[11]  V. Tvergaard.  On localization in ductile materials containing spherical voids , 1982, International Journal of Fracture.

[12]  Glenn S. Daehn,et al.  Effect of velocity on flow localization in tension , 1996 .

[13]  Sergey Fedorovich Golovashchenko,et al.  Pulsed electromagnetic attraction of sheet metals – Fundamentals and perspective applications , 2013 .

[14]  V. Tvergaard.  Influence of voids on shear band instabilities under plane strain conditions , 1981 .

[15]  Sergey Fedorovich Golovashchenko,et al.  Analysis of the Increased Formability of Aluminum Alloy Sheet Formed Using Electromagnetic Forming , 2005 .

[16]  Sergey Fedorovich Golovashchenko,et al.  The Effect of Tool–Sheet Interaction on Damage Evolution in Electromagnetic Forming of Aluminum Alloy Sheet , 2005 .

[17]  A. Needleman,et al.  Void Nucleation Effects in Biaxially Stretched Sheets , 1980 .

[18]  刘大海,et al.  Numerical modeling and deformation analysis for electromagnetically assisted deep drawing of AA5052 sheet , 2009 .

[19]  Glenn S. Daehn,et al.  Hyperplasticity: Enhanced formability at high rates , 1994 .