Production Engineering

, Volume 3, Issue 2, pp 145–156 | Cite as

Strategies to improve the geometric accuracy in asymmetric single point incremental forming

  • M. Bambach
  • B. Taleb AraghiEmail author
  • G. Hirt
Production Process


Asymmetric incremental sheet forming (AISF) is a manufacturing process for the small batch production of sheet metal parts. In AISF, a sheet metal part is formed by a forming tool that moves under CNC control. AISF currently has two dominant process limits: sheet thinning and a limited geometric accuracy. This paper focuses on the latter limit. It is shown with a pyramidal part that multi-stage forming can yield an increased accuracy compared to single-stage forming. However, due to residual stresses induced during forming, the accuracy of the as-formed part can be lost if the part is trimmed after forming. A case study with a car fender section shows that the geometric accuracy of the final part can be improved compared to single-stage forming by a combination of multi-stage forming and stress-relief annealing before trimming.


Production process Sheet metal forming Multi-stage forming 



The authors would like to thank the German Research Foundation DFG for the support of the depicted research within the Cluster of Excellence “Integrative Production Technology for High-Wage Countries”. In addition, the authors duly acknowledge that parts of the research detailed in this paper were funded by the EC through the European Collective Project FLEXFORM (contract 030273), managed by ASERM, Spain.


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Copyright information

© German Academic Society for Production Engineering (WGP) 2009

Authors and Affiliations

  1. 1.Institute of Metal Forming of RWTH AachenAachenGermany

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