Effect of the power type of the general flow function in texture simulation of ECAP

Subject Areas : journal of New Materials

Arman HASANI ¹

1 - Assistant Prof. of Mechanical Engineering, , Mechanical Engineering Group, Faculty of Engineering, University of Kurdistan, Sanandaj, Iran

Received: 2021-03-05 Accepted : 2021-11-06 Published : 2021-08-23

Keywords: Simulation, Texture, ECAP, flow function,

Abstract :

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.

References:

1.       Segal, V.M., "Equal channel angular extrusion: from macromechanics to structure formation", Materials Science and Engineering A, 271(1), pp. 322-333, 1999.

2.       Shaban Ghazani, M., "Application of the combination of extrusion and equal channel angular pressing for processing fine grained and nanostructured metallic materials", Journal of New Materials, 10(2), pp. 17-32, 2020. (In Persian)

3.       Gholinia, A., Bate, P., Prangnell, P.B., "Modeling texture development during equal channel angular extrusion of aluminum", Acta Materialia, 50, pp. 2121-2136, 2002.

4.       Tóth, L.S., et al., "Analysis of texture evolution in equal channel angular extrusion of copper using a new flow field", Acta Materialia, 52(7), pp. 1885-1898, 2004.

5.       Bagherzadeh, S., K. Abrinia, and Q. Han, "Analysis of plastic deformation behavior of ultrafine-grained aluminum processed by the newly developed ultrasonic vibration enhanced ECAP: Simulation and experiments", Journal of Manufacturing Processes, 50, pp. 485-497, 2020.

6.       Li, S., et al., "Finite element analysis of the plastic deformation zone and working load in equal channel angular extrusion", Materials Science and Engineering: A, 382(1), pp. 217-236, 2004.

7.       Beyerlein, I.J. and C.N. Tomé, "Analytical modeling of material flow in equal channel angular extrusion (ECAE) ", Materials Science and Engineering A, 380(1), pp. 171-190, 2004.

8.       Hasani, A. and Tóth, L.S., "A fan-type flow-line model in equal channel angular extrusion", Scripta Materialia, 61(1), pp. 24-27, 2009.

9.       Arruffat-Massion, R., Tóth, L.S., Mathieu, J.P., "Modeling of deformation and texture development of copper in a 120 degrees ECAE die", Scripta Materialia, 54, pp. 1667-1672, 2006.

10.   Hasani, A., Lapovok, R., Tóth, L.S., Molinari, A., "Deformation field variations in equal channel angular extrusion due to back pressure", Scripta Materialia, 58, pp. 771-774, 2008.

11.   Hasani, A. and L.S. Toth, "Deformation Field Analysis in Equal Channel Angular Extrusion of Metals Using Asymmetric Flow Function", Advanced Engineering Materials, 17(12), pp. 1760-1772, 2015.

12.   Tóth, L.S., Lapovok, R., Hasani, A., Gu, C.F., "Non-equal channel angular pressing of aluminum alloy", Scripta Materialia, 2009. 61: pp. 1121-1124.

13.   Hasani, A., Tóth, L.S. and Beausir, B., "Principles of Nonequal Channel Angular Pressing", Journal of Engineering Materials and Technology, 132(3), article 031001, 2010.

14.   Hasani, A., Tóth, L.S., and Mardokh Rouhani, S., "A New Flow Line Function for Modeling Material Trajectory and Textures in Nonequal-Channel Angular Pressing", Advances in Materials Science and Engineering, 2019, pp.1-6, 2019.

15.   Hasani, A., Sepsi, M., Feyzi, S. and Tóth, L.S., "Deformation field and texture analysis in T-ECAP using a flow function", Materials Characterization, 173, Pages 110912, 2021.

16.   Beausir, B. and Fundenberger, J.J., Analysis Tools for Electron and X-ray diffraction, ATEX - software. 2017: Université de Lorraine, Metz, France.

17.   Molinari, A. and L.S. Tóth, Tuning a self consistent viscoplastic model by finite element results—I. Modeling. Acta Metallurgica et Materialia, 1994. 42(7): pp. 2453-2458.

18.   Arzaghi, M., Beausir, B., Tóth, L.S., Contribution of non-octahedral slip to texture evolution of fcc polycrystals in simple shear, Acta. Mater., 2009, 57, 2440-2453.

Zhou, Y., K.W. Neale, and Tóth, L.S. "A modified model for simulating latent hardening during the plastic deformation of rate-dependent FCC polycrystals". International Journal of Plasticity, 1993. 9(8): pp. 961-978.