Abstract: The forming process of tube flange by one step and multiple step is researched. The FEM simulation is used to analyze the influence of tube dimension and interface friction on the material flow and the cause of forming defect. Then the relational flow and the cause of forming defect. Then the relational curves between flange width and the ultimate friction factors for two kinds of inner radius with three kinds of tube wall thickness are established. The concept of forming limit diagram for cold upsetting – forging of tube flange is presented. Experiments of cold upsetting – forging by one step of tube flange are carried out according to the FEM simulation results. The experimental results are in agreement with the numerical simulation results and illustrate that the concept of forming limit for cold upsetting – extruding of tube flange has guidance for the integral forming of tube flange.

Key words: Finite element simulation, Tube flange integral forming, 3D printing, Ceramics, Mask projection, Stereolithography