The FEM Simulation Of Ring Upsetting Process

FEM(the Finite Element Method), as a numerical simulation technique, has continuously widened its area of application in metal forming process, and was gradually changing the traditional ways in which people design and manufacture products. The upsetting process, widely applied in metal forming industry, is one of the chief methods to form the parts of nonferrous, iron and steel. In this paper, the ring upsetting process was thoroughly studied by FEM and proved by experiments, which provided some scientific basis for the determination of processing parameters. A brief introduction to the project and its main results were as follows:The theory of rigid-plastic FEM has been briefly described and the equation of penalty function deduced; some key techniques to complete the FEM simulation process have been discussed; a axial symmetry model of ring upsetting was built up, the ring upsetting of pure Al sample has been simulated by the FEM. Information about the deformed sample, such as mesh distortion, distribution of equivalent strain and stress, velocity field and load-stroke curve has been got. The deformation patterns were revealed. We got the conclusion as following:(1) Extrude status of the outer diameter will be changed bigger with the frication factor, but changed very small with the shape factor;(2) Mode for outer diameter distortion always is single extrude shape and towards outer direction, mode for inner diameter distortion will be changed from single extrude towards outer direction to inner direction with frication factor turned bigger, will be changed double extrude or multi-extrude with the shape factor turned bigger. The influence of frication and shape factors on the sample figure has been analyzed. In order to validate the FEM simulation results various experiments were designed and finished. The experiment results indicated, the simulation results are reliable.