탄소성 유한요소법에 의한 드로우비드 성형 해석

Abstract

Drawbead formulation is the first process together with a binder wrap process in a sheet metal forming process. The purpose of a drawbead is to control the flow of the metal into the die in panel press forming. To simulate the drawbead formation process, and elasto-plastic finite element formulation is derived from the equilibrium equation and related boundary conditions considering the proper contact conditions. The developed finite element program is applied to drawbead formation in the plane strain condition. The simulation of drawbead formation produces the distribution of stress and strain along the bead and the resultant elongation of the sheet in the cavity region with respect to various cavity dimensions of the sheet as well as the punch force of a drawbead and the amount of draw-in with respect to the stroke of a drawbead. The numerical results provides the fundamental information as a boundary condition to analyze the complex binder wrap phenomena and panel press forming in a simple way.