Enabling stamping processes through meticulous FE Modelling- segmented drawbeads and remesh criteria

Abstract

Drawbeads are valuable tools to control the material flow in stamping processes. Its accurate design is necessary so that the part can be formed with a minimal, and well-distributed plastic strain, and so that defects such as fractures or wrinkling can be avoided. This paper analyzes the use of a segmented drawbead to improve the results of a stamping process. Simulations, based on the Finite Elements Method, were conducted for a dual-phase 500 steel, 1.2 mm thick blank, formed using no drawbead, uniform drawbeads, and a segmented drawbead. The influence in the results of using different remesh criteria was also evaluated, and the computational time of each approach compared, the use of different criteria on the region of the blank in contact with the drawbead and the region in contact with the die and punch achieved realistic results with relatively less computational time. By adopting a segmented drawbead, it was possible to improve the results of the simulation, reducing wrinkling and fracture, based on the Forming Limit Diagram.