Route Effects in I-ECAP of AZ31B Magnesium Alloy

Abstract:

An AZ31B wrought magnesium alloy was processed by incremental equal channel angular pressing (I-ECAP) using routes A and B_C. Despite the fact that the measured grain size for both routes was very similar, the mechanical properties were different. Tensile strength was improved using route A comparing to route B_C, without ductility loss, while tension-compression anisotropy observed for route A was significantly suppressed when using route B_C. Moreover, billet shape evolution resulting from subsequent passes of I-ECAP was studied. Significant distortion after processing using route B_C and no occurrence of such effect for route A were observed. Results of a finite element analysis showed that non-uniform strain rate sensitivity might be responsible for different billet shapes. The conclusion is drawn that processing route has a strong influence on the billet shape and mechanical properties when processing magnesium alloys by I-ECAP.

• Periodical: Key Engineering Materials (Volumes 554-557)
• Pages: 876-884
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.554-557.876
• Online since: June 2013
• Authors: Michal Gzyl, Andrzej Rosochowski, Evgenia Yakushina, Paul Wood, Lech Olejnik
• Keywords: Equal-Channel Angular Pressing (ECAP), Magnesium Alloy, Ultrafine Grained Metals

References

[1] B.L. Mordike, T. Ebert, Magnesium. Properties — applications — potential, Materials Science and Engineering A 302 (2001) 37-45.

[2] V.M. Segal, V.I. Reznikov, A.E. Drobyshevskiy and V.I. Kopylov, Plastic metal working by simple shear, Russian Metallurgy 1 (1981) 115-123 (Engl. Transl.).

[3] J. Jiang, A. Ma, Bulk ultrafine-grained magnesium alloys by SPD processing：Technique, Microstructures and Properties, in: F. Czerwinski, Magnesium Alloys - Design, Processing and Properties, InTech, 2011, ISBN: 978-953-307-520-4.

DOI: 10.5772/13157

[4] A. Rosochowski, L. Olejnik, FEM simulation of incremental shear, in: E. Cueto, F. Chinesta, Proceedings of the 10th International Conference on Material Forming, Esaform 2007, April 18-20, 2007, Zaragoza, Spain, American Institute of Physics 907 (2007) 653-658.

DOI: 10.1063/1.2729587

[5] A. Rosochowski, L. Olejnik, Incremental equal channel angular pressing for grain refinement, Materials Science Forum 674 (2011) 19-28.

DOI: 10.4028/www.scientific.net/msf.674.19

[6] L. Olejnik, A. Rosochowski, M. Richert, Incremental ECAP of plates, Materials Science Forum, 584-586 (2008) 108-13.

DOI: 10.4028/www.scientific.net/msf.584-586.108

[7] A. Rosochowski, M. Rosochowska, L. Olejnik, B. Verlinden, Incremental equal channel angular pressing of sheets, Steel Research International 81 (2010) 470-73.

DOI: 10.1063/1.4963492

[8] A. Rosochowski, L. Olejnik, M. Richert, Double-billet incremental ECAP, Materials Science Forum 584-586 (2008) 139-44.

DOI: 10.4028/www.scientific.net/msf.584-586.139

[9] Y. Wu, I. Baker, An experimental study of equal channel angular extrusion, Scripta Materialia 37 (1997) 437–42.

DOI: 10.1016/s1359-6462(97)00132-2

[10] V.M. Segal, Equal channel angular extrusion: from macromechanics to structure formation, Materials Science and Engineering A 271 (1999) 322 – 333.

DOI: 10.1016/s0921-5093(99)00248-8

[11] R.B. Figueiredo, P.R. Cetlin, T.G. Langdon, Stable and unstable flow in materials processed by equal-channel angular pressing with an emphasis on magnesium alloys, Metallurgical and Materials Transactions A 41A (2009) 778-786.

DOI: 10.1007/s11661-009-0100-2

[12] R. Lapovok, L.S. Toth, A. Molinari, Y. Estrin, Strain localisation patterns under equal-channel angular pressing, Journal of the Mechanics and Physics of Solids 57 (2009) 122–136.

DOI: 10.1016/j.jmps.2008.09.012

[13] R.B. Figueiredo, P.R. Cetlin, T.G. Langdon, The processing of difficult-to-work alloys by ECAP with an emphasis on magnesium alloys, Acta Materialia 55 (2007) 4769–4779.

DOI: 10.1016/j.actamat.2007.04.043

[14] P.R. Cetlin, M.T.P. Aguilar, R.B. Figueiredo, T.G. Langdon, Avoiding cracks and inhomogeneities in billets processed by ECAP, Journal of Materials Science 45 (2010) 4561–4570.

DOI: 10.1007/s10853-010-4384-9

[15] Y. Estrin, R. Hellmig, Improving the properties of magnesium alloys by equal channel angular pressing, Metal Science and Heat Treatment 48 (2006) 504-507.

DOI: 10.1007/s11041-006-0126-7

[16] K. Xia, J.T. Wang, X. Wu, G. Chen, M. Gurvan, Equal channel angular pressing of magnesium alloy AZ31, Materials Science and Engineering A 410–411 (2005) 324–327.

DOI: 10.1016/j.msea.2005.08.123

[17] S. Seipp, M.F.-X. Wagner, K. Hockauf, I. Schneider, L.W. Meyer, M. Hockauf, Microstructure, crystallographic texture and mechanical properties of the magnesium alloy AZ31B after different routes of thermo-mechanical processing, International Journal of Plasticity 35 (2012) 155–166.

DOI: 10.1016/j.ijplas.2012.03.007

[18] W.J. Kim, C.W. An, Y.S. Kim, S.I. Hong, Mechanical properties and microstructures of an AZ61 Mg alloy produced by equal channel angular pressing, Scripta Materialia 47 (2002) 39–44.

DOI: 10.1016/s1359-6462(02)00094-5

[19] M.R. Barnett, Z. Keshavarz, A.G. Beer, D. Atwell, Influence of grain size on the compressive deformation of wrought Mg–3Al–1Zn, Acta Materialia 52 (2004) 5093–5103.

DOI: 10.1016/j.actamat.2004.07.015

[20] R.B. Figueiredo, Z. Szaraz, Z. Trojanova, P. Lukac, T.G. Langdon, Significance of twinning in the anisotropic behavior of a magnesium alloy processed by equal-channel angular pressing, Scripta Materialia 63 (2010) 504–507.

DOI: 10.1016/j.scriptamat.2010.05.016

[21] T. Fujita, Z. Horita, T.G. Langdon, Using grain boundary engineering to evaluate the diffusion characteristics in ultrafine-grained Al–Mg and Al–Zn alloys, Materials Science and Engineering A 371 (2004) 241–250.

DOI: 10.1016/j.msea.2003.12.042

[22] ABAQUS ver. 6.10 documentation.