EXPERIMENTAL AND NUMERICAL INVESTIGATION OF THE FRICTIONAL FORCES IN EQUAL CHANNEL ANGULAR PRESSING

Öz

The main limitation of the Equal Channel Angular Pressing (ECAP) is the very high required punching force for pushing the metallic sample to next channel. Frictional forces in ECAP process are responsible for very high required punching force. The participation of exit and entrance channels in total friction force has not been studied experimentally hitherto. Through the current study, two ECAP dies (1) with two channels (normal ECAP die) and (2) with only one channel (the exit channel was missed) were manufactured. Three-dimensional finite element analysis was conducted. The effect of the exit channel on the total punching force, sample geometry, and grain refinement rate were investigated experimentally and numerically. According to the results, the exit channel has a considerable effect on the amount of minimum required punching force and the grain refinement in ECAP process. The comparisons showed that, the trend of the results from experimental investigations were in good agreement with numerical analysis. 

Anahtar Kelimeler

• Equal channel angular pressing
• Friction
• Punching force
• Finite element method

Eşit Kanal Açısal Presleme Sürtünme Kuvvetlerinin Deneysel ve Sayısal İncelenmesi

Öz

Eşit Kanal Açısal Preslemenin (EKAP) temel sınırlaması, metal numuneyi kalıbın içine itmek için gereken yüksek zımbalama kuvvetidir. Gerekli yüksek zımbalama kuvvetinden EKAP sürecindeki sürtünme kuvvetleri sorumludur. Çıkış ve giriş kanallarının toplam sürtünme kuvvetine katılımı şimdiye kadar deneysel olarak incelenmemiştir. Bu çalışma sayesinde, iki kanallı (normal EKAP kalıbı) ve yalnızca bir kanallı (çıkış kanalı yok) olmak üzere iki EKAP kalıbı (1) (2) üretilmiştir. Üç boyutlu sonlu elemanlar analizi yapılmıştır. Çıkış kanalının toplam zımbalama kuvveti, numune geometrisi ve tane inceltme oranı üzerindeki etkisi deneysel ve sayısal olarak incelenmiştir. Sonuçlar, çıkış kanalının, EKAP sürecinde gerekli asgari zımbalama kuvveti miktarı ve tane inceltme üzerinde önemli bir etkiye sahip olduğunu göstermiştir. Yapılan karşılaştırmalar, deneysel araştırmaların sonuçlarının sayısal analiz ile uyumlu olduğunu göstermiştir.

Anahtar Kelimeler

• Eşit kanal açısal presleme
• Sürtünme
• Zımbalama kuvveti
• Sonlu eleman yöntemi

Kaynakça

1. Agarwal, K. M., Tyagi, R. K. and Kapoor, A. (2020) Deformation and strain analysis for grain refinement of materials processed through equal channel angular pressing, Materials Today: Proceedings, 21, 1513-1519. doi: 10.1016/j.matpr.2019.11.072.
2. Agwa, M., Ali, M. and Al-Shorbagy, A. E. (2016) Optimum processing parameters for equal channel angular pressing, Mechanics of Materials, 100, 1-11. doi: 10.1016/j.mechmat.2016.06.003.
3. Balasundar, I. and Raghu, T. (2010) Effect of friction model in numerical analysis of equal channel angular pressing process, Materials & Design, 31(1), 449-457. doi: 10.1016/j.matdes.2009.05.029.
4. Cai, G. Y., Huang, X. T. and Zhang, S. X. (2011) Finite Element Simulation of Effects of Mould Angle and Friction on ECAP for AZ80 Magnesium Alloy, Materials Science Forum, 667, 81-86. doi: 10.4028/www.scientific.net/MSF.667-669.81.
5. Djavanroodi, F. and Ebrahimi, M. (2010) Effect of die channel angle, friction and back pressure in the equal channel angular pressing using 3D finite element simulation, Materials Science and Engineering: A, 527(4-5), 1230-1235. doi: 10.1016/j.msea.2009.09.052.
6. Djavanroodi, F., Ahmadian, H., Koohkan, K. and Naseri, R. (2013) Ultrasonic assisted-ECAP, Ultrasonics, 53(6) 1089-1096. doi: 10.1016/j.ultras.2013.02.003.
7. Dumoulin, S., Roven, H., Werenskiold, J. and Valberg, H. (2005) Finite element modeling of equal channel angular pressing: Effect of material properties, friction and die geometry, Materials Science and Engineering: A, 410, 248-251. doi: 10.1016/j.msea.2005.08.103.
8. Eivani, A. and Taheri, A. K. (2008) The effect of dead metal zone formation on strain and extrusion force during equal channel angular extrusion, Computational Materials Science, 42(1), 14-20. doi: 10.1016/j.commatsci.2007.06.001.

9. Eskandarzade, M., Masoumi, A. and Faraji, G. (2016) Numerical and analytical investigation of an ultrasonic assisted ECAP process, Journal of Theoretical and Applied Vibration and Acoustics, 2(2), 167-184. doi: 10.22064/TAVA.2016.22472.
10. Eskandarzade, M., Masoumi, A., Faraji, G., Mohammadpour, M. and Yan, X.S. (2017) A new designed incremental high pressure torsion process for producing long nanostructured rod samples, Journal of Alloys and Compounds, 695(3) 539-1546. doi: 10.1016/j.jallcom.2016.10.296
11. Higuera-Cobos, O. F. and Cabrera, J. M. (2013) Mechanical, microstructural and electrical evolution of commercially pure copper processed by equal channel angular extrusion, Materials Science and Engineering: A, 571, 103-114. doi: 10.1016/j.msea.2013.01.076.
12. Jivan, R.B., Eskandarzade, M., Bewsher, S.R., Leighton, M., Mohammadpour, M., Saremi-Yarahmadi, S. (2021) Application of Solid Lubricant for Enhanced Frictional Efficiency of Deep Drawing Process, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, article in press, doi: 10.1177/0954406221994886
13. Ko, Y. and Shin, D. (2011) Microstructure and mechanical properties of nanostructured low-carbon steel prepared by equal-channel angular pressing, Nanostructured Metals and Alloys: Elsevier, 243-275. doi: 10.1533/9780857091123.2.243.
14. Miavaghi, A.S., Kangarlou, H. and Eskandarzade, M. (2017) Comparison Between Frictional Behavior of the Soft and Brittle Materials at Different Contact Pressures, Lebanese Science Journal, 18(1), 98-105. doi: 10.22453/LSJ-018.1.098105
15. Nagasekhar, A., Yoon, S., Tick-Hon, Y. and Kim, H. (2009) An experimental verification of the finite element modelling of equal channel angular pressing, Computational materials science, 46(2), 347-351. doi: 10.1016/j.commatsci.2009.03.018.
16. Patil, B. V., Chakkingal, U. and Kumar, T. P. (2008) Influence of friction in equal channel angular pressing–A study with simulation, in Proceedings of the 17th International Conference of Metallurgy and Materials (Metal 2008), Czech Rep.
17. Riazat, M. and Faraji, G. (2015) Size effect in equal channel angular pressing (ECAP) process, Journal of Advanced Materials and Processing, 3(3), 3-12.
18. Salleh, M., Ishak, N., Yahaya, S. and Abdullah, A. (2018) Effect of equal channel angular pressing on the microstructure and mechanical properties of a356 alloy, Journal of Advanced Manufacturing Technology (JAMT), 12(2), 79-92.
19. Souza, V. A., Watanabe, I. and Yanagida, A. (2016) Numerical Estimation of Frictional Effects in Equal Channel Angular Extrusion, Materials transactions, 57(9), 1399-1403. doi: 10.2320/matertrans.MH201513.
20. Taşdelen, M. and Yılmaz, İ. (2018) Cam Elyaf Katkılı Poliamid 66/Poliftalamid Karışımlarının Hazırlanması . Uludağ University Journal of The Faculty of Engineering , 23(1), 285-294 . doi: 10.17482/uumfd.350589.
21. Ulutan, M., Celik, O. N., Gasan, H. and Er, U. (2010) Effect of Different Surface Treatment Methods on the Friction and Wear Behavior of AISI 4140 Steel, Journal of Materials Science & Technology, 26(3), 251-257. doi: 10.1016/S1005-0302(10)60042-4.
22. Valiev, R. Z. and Langdon, T. G. (2006) Principles of equal-channel angular pressing as a processing tool for grain refinement, Progress in materials science, 51(7), 881-981. doi: 10.1016/j.pmatsci.2006.02.003.
23. Xu, S., Zhao, G., Ren, G. and Ma, X. (2008) Numerical simulation and experimental investigation of pure copper deformation behavior for equal channel angular pressing/extrusion process, Computational Materials Science, 44(2), 247-252. doi: 10.1016/j.commatsci.2008.03.032.
24. Yoon, S. C., Seo, M. H., Krishnaiah, A. and Kim, H. S. (2008) Finite element analysis of rotary-die equal channel angular pressing, Materials Science and Engineering: A, 490(1-2), 289-292. doi: 10.1016/j.msea.2008.01.037.