flow function

Flow line model as an efficient model in ECAP process analysis is based on functions that evaluate the material plastic flow inside the die. Among the various flow functions, the general flow function has the highest ability in analyzing of ECAP process. All parameters of this function have so far been considered as fixed parameters in calculating velocity and velocity gradient fields. Previous studies have shown a relatively linear relationship between the power in the function and the initial position of the flow lines. Accordingly, in the present work, the mentioned fields have been calculated based on the variable power and in order to investigate its effect, the experimental results of the ECAP process with an angle of 90 degree of aluminum alloy AA2124 have been used. The experimental flow lines were analyzed to find the linear relationship between the function’s power and the initial position of the flow lines. Simulations of the texture evolution were carried out subsequently using the general flow function in both constant and variable power conditions. Comparison of the simulated textures with the experimental results showed a much better performance of the variable power mode; in such a way that compared to the constant power condition, the deviation in the position of the simulated texture components in the variable power mode is significantly lower. However, the change in the power mode of the function did not show a significant effect on the intensity of the simulated texture.