Process window diagram of conical cups inhydrodynamic deep drawing assisted by radial pressure
(1. Faculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran 16785-136,Iran;
2. School of Mechanical Engineering, University of Birjand, Birjand 97175-376, Iran)
2. School of Mechanical Engineering, University of Birjand, Birjand 97175-376, Iran)
Abstract: Major defects in forming of conical cups are wrinkles and rupture. Hydrodynamic deep drawing assisted by radial pressure (HDDRP) is a sheet hydroforming process for production of shell cups in one step. In this work, process window diagrams (PWDs) for Al1050-O, pure copper and DIN 1623 St14 steel are obtained for HDDRP process. The PWD is determined to provide a quick assessment of part producibility for sheet hydroforming process. Finite element method is used for this purpose considering the process parameters including pressure path, and the blank material and its thickness. Numerical results are validated by experiments. It is shown that the sheets with less initial thickness and higher strength show better formability and uniformity of thickness distribution on final product. The results demonstrate that the obtained PWD can predict appropriate forming area and probability of rupture or wrinkling occurrence under different pressure loading paths.
Key words: conical cups; hydrodynamic deep drawing; finite element simulation; process window diagram