Estimation of Frictional Coefficient between Punch and Billet at Back-Stroke in Backward Can Extrusion Test of Steel

Abstract:

A backward can extrusion test provides severe tribological conditions because high pressure, high temperature, and large surface expansion ratio affect the lubricant. During the forward stroke these conditions intensify with increasing cup depth of the extruded workpiece; additionally, the back-stroke force during retraction of the punch rises to a significant level under a poor-lubricated condition. This study estimates the coefficient of friction μ_p between punch and workpiece during the back-stroke by combining experiments using conventional soap-phosphate coated steel and numerical analysis by FEM. The values of μ_p were estimated to be 0.09 and 0.03 in case of small and large workpiece depth, respectively. Friction decreased with elevating temperature.

• Periodical: Key Engineering Materials (Volume 767)
• Pages: 248-255
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.767.248
• Online since: April 2018
• Authors: Kazuhito Asai, Kazuhiko Kitamura, Keisuke Goto, Nobukazu Hayashi
• Keywords: Backward Cans Extrusion, Cold Forging, Friction Coefficient

References

[1] N. Bay, A. Azushima, P. Groche, I. Ishibashi, M. Merklein, H. Morishita, T. Nakamura, S. Schmid, M. Yoshida, Environmentally Benign Tribo-systems for Metal Forming, Keynote paper, CIRP Annals – Manufacturing Technology, 59/2 (2010) 760-780.

DOI: 10.1016/j.cirp.2010.05.007

[2] Z. G. Wang, S. Komiyama, Y. Yoshikawa, T. Suzuki, K. Osakada, Evaluation of lubricants without zinc phosphate precoat in multi-stage cold forging. CIRP Annals - Manufacturing Technology, 64 -1 (2015) 285-292.

DOI: 10.1016/j.cirp.2015.04.130

[3] E. Ceron, N. Bay, T. Aida, K. Dohda, T. Nicolaisen, Simulative Testing of Friction and Lubrication in Cold Forging of Steel and Aluminum. In: Proceedings of NAMRI/SME, NAMRC 40-7814 (2012) 1-10.

[4] M. Sawamura, Y. Yogo, M. Kamiyama, N. Iwata, Measurement of friction coefficient by backward extrusion with rotating tool under sever forming conditions, Procedia Engineering 81 (2014) 1866-1871.

DOI: 10.1016/j.proeng.2014.10.247

[5] T. Ohmori, K. Kitamura, A. Danno, M. Kawamura, A Cold Forging Oil Containing Phosphorus Type EP Additives. Tribology Transactions, vol.34 (1991) 458-464.

DOI: 10.1080/10402009108982057

[6] M. Takeuchi, F. Ikesus, N. Kashimura, Development of Environmentally Friendly Lubricant with Hight Performance and Simple Treatment for Cold Forging, Proceeding of the 6th ICTP, Vol.1 (1999) 383-390.

[7] H. Long, Quantitative evaluation of dimensional errors of formed components in cold backward cup extrusion, Journal of Materials Processing Technology 177 (2006) 591-595.

DOI: 10.1016/j.jmatprotec.2006.04.079

[8] T. Ishikawa, N. Yukawa, Y. Yoshida, H. Kim, Y. Tazawa, Prediction of Dimensional Difference of Product from Tool in Cold Backward Extrusion, Annals of the CIRP Vol. 49 (2000) 169-172.

DOI: 10.1016/s0007-8506(07)62921-7

[9] A. Danno, K. Abe, F. Nonoyama, Evaluation of Lubricating Performance of Zinc Phospahte Coatings by Cold Piercing Test, Journal of Japan Society for Technology of Plasticity, Vol. 24 No.265 (1983) 213-220. (in Japanese).

[10] N. Bay, M. Eriksen, X. Tan, O. Wibom: A friction model in cold forging of aluminium, steel and stainless steel provided with conversion coating and solid film lubricant, CIRP Annals, Manufacturing Technology, Vol. 60/1 (2011) 303-306.

DOI: 10.1016/j.cirp.2011.03.143