Constitutive Behavior of AZ31 Magnesium Tube Processed by Severe Plastic Deformation

Document Type : Research Paper


Department of Mechanical Engineering, Faculty of Engineering, University of Hormozgan, Bandar Abbas, 7916193145, Iran


In this study, the evolution of parallel tubular channel angular pressing (PTCAP) as a severe plastic deformation process on the hot deformation behavior of the extruded AZ31 magnesium tube was investigated. After four passes, a more refined and homogeneous microstructure was achieved. To understand constitutive behavior, hot tensile tests were carried out on four passes of specimens at temperatures of 350, 400, and 450ºC with strain rates of 0.0001, 0.001, and 0.01 s-1. The dependence of flow stress on strain rate and temperature was investigated by the Zener-Hollomon equation and the activation energy was found to be around 131.26 kJ/mol. Effect of strain was included in the constitutive equation by applying material constants. Based on the constitutive model, the stress-strain curves of PTCAP processed tubes were extracted and compared with the experimental curves. The results indicate good agreement between experimental and predicted flow curves by considering the softening effect.


[1]    L.S. Toth, C. Chen, A. Pougis, M. Arzaghi, J.J. Fundenberger, R. Massion, S. Suwas, High pressure tube twisting for producing ultra fine grained materials: a review, Materials Transactions, 60(7) (2019) 1177-1191.
[2]    M.S. Mohebbi, A. Akbarzadeh, Accumulative spin-bonding (ASB) as a novel SPD process for fabrication of nanostructured tubes, Materials Science and Engineering: A, 528(1) (2010) 180-188.
[3]    A. Babaei, M.M. Mashhadi, H. Jafarzadeh, Tube cyclic expansion-extrusion (TCEE) as a novel severe plastic deformation method for cylindrical tubes, Journal of Materials Science, 49(8) (2014) 3158-3165.
[4]    G. Faraji, M.M. Mashhadi, K. Abrinia, H.S. Kim, Deformation behavior in the tubular channel angular pressing (TCAP) as a noble SPD method for cylindrical tubes, Applied Physics A, 107(4) (2012) 819-827.
[5]    G. Faraji, H.S. Kim, Review of principles and methods of severe plastic deformation for producing ultrafine-grained tubes, Materials Science and Technology, 33(8) (2017) 905-923.
[6]    G. Faraji, A. Babaei, M.M. Mashhadi, K. Abrinia, Parallel tubular channel angular pressing (PTCAP) as a new severe plastic deformation method for cylindrical tubes, Materials Letters, 77 (2012) 82-85.
[7]    M. Barnett, Influence of deformation conditions and texture on the high temperature flow stress of magnesium AZ31, Journal of light metals, 1(3) (2001) 167-177.
[8]    Z.M. Liu, S.M. Xing, P.W. Bao, L. Nan, S.Q. Yao, M.L. Zhang, Characteristics of hot tensile deformation and microstructure evolution of twin-roll cast AZ31B magnesium alloys, Transactions of Nonferrous Metals Society of China, 20(5) (2010) 776-782.
[9]    J. Deng, Y. Lin, S.S. Li, J. Chen, Y. Ding, Hot tensile deformation and fracture behaviors of AZ31 magnesium alloy, Materials & Design, 49 (2013) 209-219.
[10]  W.G. Yang, C.H. Koo, Improving the mechanical properties of Mg-8Al magnesium alloy by the re addition and hot extrusion, Bulletin of the College of Engineering, NTU, 89 (2003) 63-82.
[11]  F.X. Chen, X.Z. Chen, F.T. Sun, Superplastic behavior and constitutive equation of AZ31B magnesium alloy, Applied Mechanics and Materials, Trans Tech Publ, 2012, pp. 1689-1692.
[12]  H.J. McQueen, N. Ryan, Constitutive analysis in hot working, Materials Science and Engineering: A, 322(1-2) (2002) 43-63.
[13]  C. Zener, J.H. Hollomon, Effect of strain rate upon plastic flow of steel, Journal of Applied physics, 15(1) (1944) 22-32.
[14]  E. Doege, K. Dröder, Sheet metal forming of magnesium wrought alloys—formability and process technology, Journal of Materials Processing Technology, 115(1) (2001) 14-19.
[15]  R.E. Smallman, Modern physical metallurgy, Elsevier, 2016.
[16]  Z.Q. Sheng, R. Shivpuri, Modeling flow stress of magnesium alloys at elevated temperature, Materials Science and Engineering: A, 419(1-2) (2006) 202-208.
[17]  M.S. Arun, U. Chakkingal, A constitutive model to describe high temperature flow behavior of AZ31B magnesium alloy processed by equal-channel angular pressing, Materials Science and Engineering: A, 754 (2019) 659-673.
[18]  I. Schindler, P. Opěla, P. Kawulok, M. Sauer, S. Rusz, D. Kuc, K. Rodak, Hot deformation activation energy of metallic materials influenced by strain value, Archives of Metallurgy and Materials, 66 (2021).
[19]  H. Takuda, H. Fujimoto, N. Hatta, Modelling on flow stress of Mg–Al–Zn alloys at elevated temperatures, Journal of Materials Processing Technology, 80 (1998) 513-516.
[20]  H. Takuda, T. Morishita, T. Kinoshita, N. Shirakawa, Modelling of formula for flow stress of a magnesium alloy AZ31 sheet at elevated temperatures, Journal of Materials Processing Technology, 164 (2005) 1258-1262.
[21]  M. Eftekhari, A. Fata, G. Faraji, M.M. Mashhadi, Hot tensile deformation behavior of Mg-Zn-Al magnesium alloy tubes processed by severe plastic deformation, Journal of Alloys and Compounds, 742 (2018) 442-453.
[22]  A. Fata, M. Eftekhari, G. faraji, M. Mosavi, Effects of PTCAP as a severe plastic deformation method on the mechanical and microstructural properties of AZ31 magnesium alloy, Modares Mechanical Engineering, 17(12) (2018) 409-416.
[23]  P. Changizian, A. Zarei-Hanzaki, A.A. Roostaei, The high temperature flow behavior modeling of AZ81 magnesium alloy considering strain effects, Materials & Design, 39 (2012) 384-389.
[24]  F.S.J. Poggiali, C.L.P. Silva, P.H.R. Pereira, R.B. Figueiredo, P.R. Cetlin, Determination of mechanical anisotropy of magnesium processed by ECAP, Journal of Materials Research and Technology, 3(4) (2014) 331-337.
[25]  Q. Guo, H.G. Yan, H. Zhang, Z.H. Chen, Z.F. Wang, Behaviour of AZ31 magnesium alloy during compression at elevated temperatures, Materials Science and Technology, 21(11) (2005) 1349-1354.
[26]  A. Fata, G. Faraji, M. Mashhadi, V. Tavakkoli, Hot tensile deformation and fracture behavior of ultrafine-grained AZ31 magnesium alloy processed by severe plastic deformation, Materials Science and Engineering: A, 674 (2016) 9-17.
[27]  C.M. Sellars, W.J. McTegart, On the mechanism of hot deformation, Acta Metallurgica, 14(9) (1966) 1136-1138.
[28]  Y.Q. Cheng, H. Zhang, Z.H. Chen, K.F. Xian, Flow stress equation of AZ31 magnesium alloy sheet during warm tensile deformation, Journal of Materials Processing Technology, 208(1-3) (2008) 29-34.