Numerical Simulation of a Pyramid Steel Sheet Formed by Single Point Incremental Forming Using Solid-Shell Finite Elements

Single Point Incremental Forming (SPIF) is an interesting manufacturing process due to its dieless nature and its increased formability compared to conventional forming processes. Nevertheless, the process suffers from large geometric deviations when compared to the original CAD profile. One particular example arises when analyzing a truncated two-slope pyramid [. In this paper, a finite element simulation of this geometry is carried out using a newly implemented solid-shell element [, which is based on the Enhanced Assumed Strain (EAS) and the Assumed Natural Strain (ANS) techniques. The model predicts the shape of the pyramid very well, correctly representing the springback and the through thickness shear (TTS). Besides, the effects of the finite element mesh refinement, the EAS and ANS techniques on the numerical prediction are presented. It is shown that the EAS modes included in the model have a significant influence on the accuracy of the results.

[1]  Joost Duflou,et al.  Study of the geometrical inaccuracy on a SPIF two-slope pyramid by finite element simulations , 2012 .

[2]  Laurent Duchene,et al.  Assessment of the enhanced assumed strain (EAS) and the assumed natural strain (ANS) techniques in the mechanical behavior of the SSH3D solid-shell element , 2011 .

[3]  Joost Duflou,et al.  Investigation of Deformation Phenomena in SPIF Using an In-Process DIC Technique , 2009 .

[4]  C. Henrard,et al.  Forming forces in single point incremental forming: prediction by finite element simulations, validation and sensitivity , 2011 .

[5]  Jun Gu,et al.  Strain evolution in the single point incremental forming process: digital image correlation measurement and finite element prediction , 2011 .

[6]  Joost Duflou,et al.  Accuracy Improvement in Single Point Incremental Forming through Systematic Study of Feature Interactions , 2011 .

[7]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[8]  A. H. van den Boogaard,et al.  An overview of stabilizing deformation mechanisms in incremental sheet forming , 2009 .

[9]  Joost Duflou,et al.  Adaptive remeshing for incremental forming simulation , 2008 .

[10]  Jeong Whan Yoon,et al.  On the use of a reduced enhanced solid-shell (RESS) element for sheet forming simulations , 2007 .

[11]  P ? ? ? ? ? ? ? % ? ? ? ? , 1991 .

[12]  A. H. van den Boogaard,et al.  The technology of Incremental Sheet Forming¿A brief review of the history , 2010 .

[13]  K. Bathe,et al.  A continuum mechanics based four‐node shell element for general non‐linear analysis , 1984 .

[14]  J. C. Simo,et al.  A CLASS OF MIXED ASSUMED STRAIN METHODS AND THE METHOD OF INCOMPATIBLE MODES , 1990 .

[15]  A. H. van den Boogaard,et al.  Substructuring in the implicit simulation of single point incremental sheet forming , 2009 .

[16]  Ricardo J. Alves de Sousa,et al.  Evaluation of the Enhanced Assumed Strain and Assumed Natural Strain in the SSH3D and RESS3 Solid Shell Elements for Single Point Incremental Forming Simulation , 2012 .