Journal of the Japan Society for Technology of Plasticity
Online ISSN : 1882-0166
Print ISSN : 0038-1586
ISSN-L : 0038-1586
Boss Forming Limit by Bottom Compression Drawing
Zhigang WANGMasanao KARASAWAWataru KATOH
Author information

2012 Volume 53 Issue 616 Pages 434-438


Backward extrusion is the most common method of forming bosses within product cases. However, backward extrusion requires a very large forming load. To overcome this disadvantage, we developed bottom compression drawing to replace backward extrusion in our previous study. In this study, the formability and boss forming limit in bottom compression drawing are investigated by a series of experiments and finite element analysis. The results showed that the failure at the punch shoulder occurs when the radial tensile stress at the punch shoulder reaches the tensile strength of the sheet metal. With increasing surface roughness of the counterpunch, the formable zone of a solid boss expands. Adhesion on the counterpunch surface can be observed with repeated forming cycles under a dry condition, but the irregularity in the product configuration converges to a befitting level after a few forming cycles.

Information related to the author
© 2012 The Japan Society for Technology of Plasticity
Previous article Next article