A study on the improvement of formability for elliptical deep drawing processes

The punch and die corner radii, the lubricant condition, the working speed, the blank-holding force, the friction force and the clearance change the f ormability of the deep drawing process. In general, sheet metal forming may involve stretching, drawing or various combinations of these basic modes o f deformation. The influence of the punch and die corner radii is of great importance in the design of sheet metal working processes. Recently, most o f the research for the sheet metal deep drawing process has been performed on the formability of an axisymmetric shape, but there are not any concrete reports on the formability of a non-axisymmetric shape. In addition. the c onventional corner radii of the punch and die have been determined by trial -and-error using industrial experience and post-processing tests, and only approximate corner radii of the punch and die have been presented. In order to obtain the optimal products in the deep drawing process, elliptical dee p drawing tests were carried out with several corner radii of the punch and die. In this study, the optimal corner radii of the punch and die in the d eep drawing process with a non-axisymmetric blank shape are proposed. Resea rch has been carried out using diverse technologies including experimentati on and the finite element method. (C) 2001 Elsevier Science B.V. All rights reserved.