The Porosity Evaluation during ECAP in Aluminium PM Alloy

• Authors: J. Bidulská , T. Kvačkaj , R. Bidulský , M. Actis Grande
• Languages of publication: EN

Abstracts

EN

The main aim of this paper is to show porosity evolution during application of various processing conditions including pressing, sintering and equal channel angular pressure. An aluminium based powder (Al-Mg-Si-Cu-Fe) was used as investigated material. After applying different pressing pressures (400 and 600 MPa), specimens were dewaxed in a ventilated furnace at 400C for 60 min. Sintering was carried out in a vacuum furnace at 610C for 30 min. The specimens were processed by single equal channel angular pressure pass. A significant disadvantage of powder metallurgy processing methods is the presence of porosity. Pores act as crack initiators and, due to their presence, the distribution of stress is inhomogeneous across the cross-section and leads to reduction of the effective load bearing area. The equal channel angular pressure process, causing stress distribution in deformed specimens, made the powder particles to squeeze together to such an extent that the initially interconnected pores transform to small isolated pores. The proposed safety diagram includes the combined effect of stress and strain behaviour during equal channel angular pressure. The "safety line" eliminates and quantifies the effect of large pores as a potential fracture initiation sites with respect to the mechanical viewpoint.

Keywords

EN

81.05.Bx; 81.07.Bc; 81.20.Ev; 81.40.-z

Discipline

• 81.40.-z: Treatment of materials and its effects on microstructure, nanostructure, and properties
• 81.20.Ev: Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
• 81.07.Bc: Nanocrystalline materials
• 81.05.Bx: Metals, semimetals, and alloys

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2012
• Volume: 122
• Issue: 3
• Pages: 553-556

Dates

published

2012-09

Contributors

author

J. Bidulská

• Department of Metals Forming, Faculty of Metallurgy, Technical University of Košice, Letná 9, 042 00 Košice, Slovakia

author

T. Kvačkaj

• Department of Metals Forming, Faculty of Metallurgy, Technical University of Košice, Letná 9, 042 00 Košice, Slovakia

author

R. Bidulský

• Politecnico di Torino, Sede di Alessandria, 15 100, T. Michel, 5, Alessandria, Italy

author

M. Actis Grande

• Politecnico di Torino, Sede di Alessandria, 15 100, T. Michel, 5, Alessandria, Italy

References

• [1] X. Wu, W. Xu, K. Xia, Mater. Sci. Eng. A 493, 241 (2008)
• [2] J. Bidulská, T. Kvačkaj, R. Kočiško, R. Bidulský, M. Actis Grande, Mater. Sci. Forum 667-669, 535 (2011)
• [3] R. Kocisko, P. Zubko, J. Durisin, M. Molnarova, A. Kovacova, M. Kvackaj, J. Bacso, Chem. Listy 104, 330 (2010)
• [4] M. Kvačkaj, T. Kvačkaj, A. Kováčová, R. Kočiško, J. Bacsó, Acta Metall. Slovaca 16, 84 (2010)
• [5] R. Kočiško, T. Kvačkaj, J. Bidulská, M. Molnárová, Acta Metall. Slovaca 15, 228 (2010)
• [6] S. Haltner, A. Wehrli, M. Gassmann, Metal Powder Rep. 61, 17 (2011)
• [7] T. Rausch, P. Beiss, Ch. Broeckmann, S. Lindlohr, R. Weber, Proc. Eng. 2, 1283 (2010)
• [8] M. Jeandin, S. Rupp, J. Massol, Y. Bienvenu, Mater. Sci. Eng. 77, 139 (1986)
• [9] B. Kubicki, Powder Metall. 38, 295 (1995)
• [10] R.T. DeHoff, E.H. Aigeltinger, Proceedings of Perspectives in Powder Metallurgy, Plenum Press, New York 1970, Vol. 5, p. 81
• [11] T. Marcu Puscas, M. Signorini, A. Molinari, G. Straffelini, Mater. Charact. 50, 1 (2003)
• [12] R. Bidulský, J. Bidulská, M. Actis Grande, High Temp. Mater. Process. 28, 337 (2009)
• [13] J. Bidulská, R. Kočiško, R. Bidulský, M. Actis Grande, T. Donič, M. Martikán, Acta Metall. Slovaca 16, 4 (2010)
• [14] J. Bidulská, T. Kvačkaj, R. Kočiško, R. Bidulský, M. Actis Grande, T. Donič, M. Martikán, Acta Phys. Pol. A 117, 864 (2010)
• [15] J. Bidulská, T. Kvačkaj, R. Kočiško, R. Bidulský, M. Actis Grande, J. Electr. Eng.-Slovaca 28, 308 (2010)
• [16] M. Actis Grande, R. Bidulský, J. Bidulská, T. Kvačkaj, Adv. Mater. Res. 189-193, 2838 (2011)
• [17] J. Bidulská, T. Kvačkaj, R. Bidulský, M. ActisGrande, L. Lityńska-Dobrzyńska, J. Dutkiewicz, Chem. Listy 105, s471 (2011)
• [18] R.M. German, P. Suri, S.J. Park, J. Mater. Sci. 44, 1 (2009)
• [19] G.B. Schaffer, T.B. Sercombe, R.N. Lumley, Mater. Chem. Phys. 67, 85 (2001)
• [20] J.M Martin, F Castro, J. Mater. Process. Technol. 143-144, 814 (2003)
• [21] C.C. Koch, J. Metastable Nanocryst. Mater. 18, 9 (2003)
• [22] P. Beiss, M. Dalgic, Mater. Chem. Phys. 67, 37 (2001)
• [23] A. Salak, V. Miskovic, E. Dudrova, E. Rudnayova, Powder Metall. Inter. 6, 128 (1974)
• [24] G.F. Bocchini, Int. J. Powder Metall. 22, 185 (1986)
• [25] A. Salak, Ferrous Powder Metallurgy, Cambridge International Science Publishing, Cambridge 1995, p. 453
• [26] S. Saritas, R.J. Causton, W.B. James, A. Lawley, Adv. Powder Metall. Part. Mater. 10, 51 (2001)
• [27] L. Fuentes-Pacheco, M. Campos, Sci. Sinter. 41, 161 (2009)
• [28] R.Y. Lapovok, D. Tomus, J. Mang, Y. Estrin, T.C. Lowe, Acta Mater. 57, 2909 (2009)
• [29] Nanostructured Materials: Processing, Properties and Potential Applications, Ed. C.C. Koch, Noyes Publications, New York 2002

Identifiers

DOI

10.12693/APhysPolA.122.553