Investigation Of Precision Plastic Forming Process For The Special-shaped Wave-guide

Special-shaped wave-guide plays an important role in radar system, so there is higher quality requirement on geometry. The advantages and disadvantages of four different kinds of machining processes including machine-finishing, the precision casting, the drawing and the jointing were analyzed, the sheet drawing processing plan was selected. In order to improve production efficiency, and ensure the symmetry and vertical degree of part, according to the features of part shape and comparing four different kinds of deep drowning processes, four-one plate deep drawing and reverse redrawing process was introduced to warm forming, it is available to control and decrease crack, wrinkle. Therefore, there are some important academic and practical meanings of the forming theory. Special-shaped wave-guide forming process and die design were researched in this paper.In the first part, Special-shaped wave-guide forming process was simulated by the DEFORM-3D software. The simulation results show that flat-bottomed punch will lead the fracture in the deep drawing process. In order to avoid the failure part in the next step, the spherical punch was used as the solution of the fracture elimination and prevention, which is the effective references and guidelines to the deep drawing production.Secondly, by calculating the grey relational generating between objective function (parietal thickness, bottom thickness, max height) and ideal single objective value, the multi-objectives optimization process parameters (the friction coefficient, temperature, punch-die angle, the diameter of the hole) were gained based on the grey system theory. Then, the optimization process parameters were employed to simulate the special-shaped wave-guide forming, and the simulation results demonstrate that forming quality is obviously improved.Finally, according to the forming process and practical condition, the design of heat preservation, spherical punch, and the spring which connected spherical punch with die holder make the process of deep drawing and reverse redrawing achieved in one set of mold. In the extrusion die design, a flute was applied to decrease the forming force and prolong the die service life based on the local loading theory.