An investigation of material flow pattern in extrusion of Axis-symmetric square shape section

Understanding and formulating the material flow helps us to determine the optimum shape of the die andimportant details of the process. In this paper, physical modeling of forward extrusion of Axis-symmetric circle-to-circle and circle-to-square section has been carried out and the upper bound theory has been used to derive the velocity field. In analytical methodthe velocity profile has been formulated using curved surfaces to define the entry and exit surfaces of the deforming zone. Indeed a Bezier function has been used to determine a good velocity field. It should be mention that there is codding which was written by MATLAB to obtain the velocity of material in the process based on the upper bound theory. The forward extrusion process was physically simulated by plasticine material. Using the results of the physical modeling flow patterns for the extrusion of shaped sections was determined at longitudinal plane. Using these data the theoretical model was improved in order to make better flow predictions for the die design purposes

کلیدواژه ها:

forward extrusion ، physical modeling ، material flow pattern ، upper bound theory