Surface distortions are frequently introduced into the Class “A” surfaces during various sheet metal forming operations such as drawing, trimming and flanging. The origins of those surface distortions have not been well understood. The scope of this research is to investigate the distortion that occurs in draw operation and to find effective and practical corrective methods. Five geometric parameters are first identified to represent a typical depression feature in automobile outer panels. Experimental dies are then designed to reflect various combinations of these five geometric parameters with the assistance of numerical simulations to ensure that the dies can make parts free of major defects like splits and wrinkles. Surface distortions are observed in our stamping experiments and various techniques are used to measure and record the distortions for further mathematical analysis. Historical data of strains and deflections in distortion areas are collected through real time measurement. The effects of three geometry parameters on distortion are analyzed using a full factorial DOE model. Finally, four approaches that aim to correct distortions are tried out and die morphing proves to be a practical and effective method.
Investigation and Correction of Sheet Metal Distortion in Draw Operation
Sae Technical Papers
SAE 2010 World Congress & Exhibition ; 2010
2010-04-12
Conference paper
English
Prototype draw dies for sheet metal parts
Automotive engineering | 1998
|Prototype Draw Dies for Sheet Metal Parts
SAE Technical Papers | 1998
|Characteristics of work load on form and draw forming of metal sheet
British Library Conference Proceedings | 2012
|Nonparametric Correction of Distortion
British Library Conference Proceedings | 1996
|Tool material performance during draw bead deformation of aluminum sheet
Automotive engineering | 1996
|