Forming Arbitrary Curved Shapes Without Dies

7 Forming Arbitrary Curved Shapes Without Dies 

Cold bends (insufficient interply sliding in main forming region) 

Complete success, however, was not attained in the initial version. The limiting factor was the development of overcurvature in the formed components. This was shown to be due to an incompatibility strain which arises between the formed and not-yet-formed regions on any one pass through the forming machine. Using an energy minimization model, the overcurvature was shown to be inherent to the process. 

Continuous dieless forming was then used to form both uniform-curvature and non-uniform curvature components. Good shape accuracy (i.e., maximum deviation of 0.4 mm or 0.016 in.) was attained. A key ingredient proved to be manipulation of the temperature gradient across the forming roller. 

This chapter is a summary of work conducted by members of the author s polymer composites research group at Stanford, including Karthik Ramani, Steve Yencho, Micha Gur, Yosef Gertner, Adi Peled, Margaret Talbott, Rick Vinci, Calvin Chang, Eric Menzel, and Alex Payne. Collaboration with Prof. Mark Cutkosky was very helpful. Each individual made many contributions, most of which have been identified in the text, but all are thanked here again. 

---

Forming Arbitrary Curved Shapes Without Dies. 435... 

---