Possibility of Deformation of Billet with Various Internal Structure in KOBO Extrusion

Abstract:

The potential of KOBO unconventional extrusion of metallic materials based on phenomenon of changing the path of plastic deformation with use of cyclic oscillation of the die by given angle and frequency has been presented in this paper. This process is used to change material properties by fragmentation of grains without preheating the billet and press parts with significantly lower extrusion force in comparison to conventional process. Various types of billets (various metallic materials in the form of: solid initial material, condensed chips, layered composite material) were used during the experimental tests to analyze the plastic flow of the material and the possibility of plastic deformation of various metallic materials such as aluminum alloys, magnesium alloys and copper in order to obtain a product with a complex shape in the KOBO process, using dies with different geometries. Mechanical properties, microstructure, scheme of plastic flow and extrusion force were examined during experimental work. KOBO extrusion can be considered as a more cost-effective process than conventional extrusion.

• Periodical: Key Engineering Materials (Volume 926)
• Pages: 511-522
• DOI: https://doi.org/10.4028/p-32j6m1
• Online since: July 2022
• Authors: Marek Zwolak*, Romana Ewa Śliwa, Beata Pawłowska, Aleksandra Wędrychowicz
• Keywords: Aluminum Alloy, Extrusion Load, KOBO Extrusion, Magnesium Alloy, Plastic Flow

References

[1] A. Korbel, W. Bochniak, Method of plastic forming of materials, U.S. patent 5.737.959 (1998); European Patent 0.711.210 (2000).

[2] W. Bochniak, Teoretyczne i praktyczne aspekty plastycznego kształtowania metali, metoda KOBO, Wydawnictwo AGH, Kraków (2009).

[3] A. Korbel, W. Bochniak, R.Śliwa,P. Ostachowski, M. Łagoda, Z. Kusion, B. Trzebuniak, Niskotemperaturowa konsolidacja wiórów z trudnoodkształcalnych stopów aluminium, Obróbka Plastyczna Metali, t. XXVII nr. 2, (2016), 133-151.

[4] K. Topolski, W. Bochniak, M. Łagoda, P. Ostachowski, Structure and properties of titanium produced by new method of chip recycling,, Journal of Materials Processing Technology 248(2017) 80-91.

DOI: 10.1016/j.jmatprotec.2017.05.005

[5] J. Maciejewski, Z. Mróz, Analiza procesu wyciskania metali wspieranego deformacją cykliczną, Rudy Metale R52,nr 11 (2007), 668-677.

[6] A. Korbel, W. Bochniak, A method of extruding materials, Patent report no. 174474 (1998).

[7] A. Korbel, W. Bochniak, Method of plastic forming of materials, U.S. Patent no 5,737,959 (1998).

[8] R.Z. Valiev, R.K. Islamgaliev, I.V. Alexandrov, Bulknanostructured materials from severe plastic deformation, Prog. Mater. Sci., 45 (2000), 103-189.

DOI: 10.1016/s0079-6425(99)00007-9

[9] T.G. Langdon, Twenty-five years of ultrafine-grained materials: Achieving exceptional properties through grain refinement, Acta Materialia, Volume 61, Issue 19, (2013) 7035 – 7059.

DOI: 10.1016/j.actamat.2013.08.018

[10] M. Wronski, K. Wierzbanowski, L.Pytlik, B. Bacroix, M.Wróbel, A.Baczmanski, A.Lodini, Study of microstructure, texture and residualstress in asymmetricallyrolledtitanium, Materials Science ForumVolume 777 (2014) 1– 6.

DOI: 10.4028/www.scientific.net/msf.777.1

[11] D.Andrzejewski, J.Jakubowicz, J.Borowski, Structure and properties of 7075 aluminum alloy products obtained with the KOBO method, Archives of Civil and Mechanical Engineering 16 (2016) Pages 217-223.

DOI: 10.1016/j.acme.2015.10.005

[12] W. Bochniak, K. Marszowski, A.Korbel, Theoretical and practical aspects of the production of thin-walled tubes by the KOBOmetod, Journal of Materials Processing Technology ,Volume 169, Issue 1, (2005) 44-53.

DOI: 10.1016/j.jmatprotec.2005.02.258

[13] K. Pieła, M. Wróbel, K. Sztwiertnia, M. Jaskowski, J. Kawałko, M. Bieda, M. Kiper, A. Jarzębska, Zinc subjected to plastic deformation by complex loading and conventional extrusion: Comparison of the microstructure and mechanical properties, Materials & Design 117 (2017) 111-120.

DOI: 10.1016/j.matdes.2016.12.056

[14] K. Kowalczyk-Gajewska, K. Sztwiertnia, J. Kawałko,K. Wierzbanowski, M. Wroński, K.Frydrych, S.Stupkiewicz, H.Petryk, Texture evolution in titanium on complex deformation paths: Experiment and modelling, Materials Science and Engineering 637, (2015) 251-263.

DOI: 10.1016/j.msea.2015.04.040