Draw-Bead Analysis with 3-D Shell Element for the Equivalent Boundary Condition in Forming Analysis

Abstract

This paper is concerned with the estimation and application of the boundary condition for draw-bead to finite element analysis of sheet metal forming using the equivalent draw-bead. Bead forming analysis and drawing analysis are newly carried out with 3-D shell element. Parameter studies are also performed with the variation of the blank length, the draw-bead depth and the friction in order to evaluate the effect of those parameters on the equivalent boundary condition. The equivalent boundary condition can be applied to sheet metal forming analysis as the displacement in the region of draw-bead as well as the restraining force of draw-bead. Sheet metal forming simulation is performed using the equivalent boundary condition and investigated comparing with the real product especially for the thickness variations. The result fully demonstrates that finite element forming simulation with the equivalent boundary condition estimated with 3D shell element is accurate and highly reliable.