DESIGN OF SPRINGBACK-FREE STRUCTURAL STAMPED PART USING TOPOGRAPHY OPTIMISATION

Abstract

The real challenge in designing sheet metal stamped part is always on how to compensate for springback errors. Traditionally, more often than not, the problem is left for the tool designer to solve. This thesis describes a new methodology for generating a springback-free automotive structural part design by topography optimisation. Unlike the conventional method for springback compensation which is done on the die face, this new innovative approach proposes similar compensation but to be carried out on the part surface. By using a Numisheet 2008 benchmark part called Straight Rail; the first attempt was to investigate the effect of location and size of beads on the part surface to springback errors. The results were conclusive as the bead pattern at certain location reduced the part springback significantly. Similar results were also obtained when the bead patterns were automatically generated by Topography optimisation technique. A methodology for generating springback-free part design was then developed based on this concept. Finally the methodology was validated by using two Numisheet 2008 S-Rail and U-Bend parts. Simulation results show the new approach was able to significantly reduce springback error within the industry accepted tolerance of ±0.Smm. The same methodology can now be used by the part designer to produce springback-free sheet metal part.