Abstract
A new draw bending process using a double-action punch, consisting of inner and outer punches, has been developed to control the springback of the formed parts in high-strength steel sheets. In this process, the draw bending by the inner punch is followed by the reverse draw bending by the outer punch. By performing hat-shaped draw bending experiments, it was confirmed that the above-mentioned sequential punch actions, with the application of an appropriate stretching force to the sheets by a controlled blank holding force, allow us to obtain completely flat flange and noncurled side walls of the hat-shaped part in 980MPa high-strength steel sheets. Such a marked decrease in springback is due to the reduction in bending moment by sequential bending and unbending under a large stretching force.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
