High Speed Railway Hollow Axle Radial Forging Process Simulation Study

With the development of high-speed railway in China, it is imperative under the situation to utilizing hollow axle. Compared with solid axle, the forging process of hollow axle is more superior. It is remarkable for material and energy saving, stands for advanced forging technology on hollow axle forging. The radial forging of axles belongs to three-dimensional forming, for its features of instantaneous locality and continuity, large quantity of calculation is required. Up to now, interrelated papers are seldom reported about simulative study of the hollow axle on precise radial forging. Joseph P. Domblesky transformed it into two-dimensional problems to calculate by FEM, it is not reported in China by now.In this paper, firstly, testing thermal simulation of 50 and 25CrMo4 steel are proceeded by the Gleeble-1500D thermal force testing machine, constitutive relationship of the two materials is obtained. Then according to the dimension of the part and the result of previous simulation, proper dimension of the blank is determined and hollow axle without mandrel is simulated by the DEFORM-3D software, proper processing parameters are determined. The conclusion is gotten that integral quality of the forging piece is better and strain distribution is comparatively homogeneous when the radial depress value of hammer is 8mm, and the axial amount of feed is 80mm. Secondly, on this basic, analogy calculation of thermal transmittance between hammer and work-piece is proceeded and the exchange of heat between the two is basically no effect on the final quality of the forging piece. Thirdly, numerical simulation research on the hollow axle of new material 25CrMo4 radial forging is proceeded and the simulation results of the two materials are done a comparative analysis.Through numerical simulation of axle forging processing,it is disclosed the regularity of material flow and forming distribution, the whole technical process is verified. It is convenient to research and improve the radial forging process of axle.