Effect of Deformation Temperature on Microstructure and Mechanical Properties of AZ31 Mg Alloy Processed by Differential-Speed Rolling

doi:10.1016/j.jmst.2014.08.016

Abstract

Abstract: A differential-speed rolling (DSR) was applied to AZ31 magnesium alloy sample at different rolling temperatures of 473, 523, 573, and 623 K with 1-pass and 2-pass operations. The microstructural evolution and mechanical properties of the deformed samples were investigated. The rolling temperature was found to be an important parameter affecting the microstructural development. After DSR at 473 K, the microstructure was more homogeneous than that obtained after deformation by equal-speed rolling (ESR). The fully recrystallized microstructures were generated after DSR at 573 and 623 K. As to mechanical properties, the yield strength (YS) and ultimate tensile strength (UTS) decreased monotonously with increasing rolling temperature. In contrast, the elongation of the DSR-deformed samples was improved as the rolling temperature increased. The strain hardening exponent (n) calculated by Hollomon equation increased with increasing the rolling temperature, which would explain an increase in the uniform elongation.

Key words: Differential-speed rolling, Magnesium alloy, Mechanical properties, Strain hardening

Mosab Kaseem, Bong Kwon Chung, Hae Woong Yang, Kotiba Hamad, Young Gun Ko. Effect of Deformation Temperature on Microstructure and Mechanical Properties of AZ31 Mg Alloy Processed by Differential-Speed Rolling[J]. J. Mater. Sci. Technol., 2015, 31(5): 498-503.

Figures/Tables 7

Optical image of the initial microstructure of AZ31 Mg alloy sample.

Optical images of AZ31 Mg samples deformed by ESR at 473 K after (a) 1-pass and (b) 2-pass ESR operations.

Optical images of AZ31 Mg samples deformed by DSR with different conditions: (a) 1-pass at 473 K, (b) 2-pass at 473 K, (c) 1-pass at 523 K, (d) 2-pass at 523 K, (e) 1-pass at 573 K, (f) 2-pass at 573 K, (g) 1-pass at 623 K, (h) 2-pass at 623 K.

Grain size variations of AZ31 Mg alloy samples deformed by ESR and DSR at different temperatures.

Engineering stress vs strain curves of the DSR-deformed samples after (a) 1-pass and (b) 2-pass DSR operations.

Tensile properties of the DSR-deformed AZ31 alloy samples with respect to deformation temperature after (a) 1-pass and (b) 2-pass DSR operations.

Plots of lnσ

References

[1] B. Chen, C. Lu, D. Lin, X. Zeng, Met. Mater. Int. , 20 (2014), pp. 285-290
[2] S. Jeong, J. Park, I. Choi, S.H. Park, Korean J. Met. Mater. , 51 (2013), pp. 701-711
[3] S. Jeong, Met. Mater. Int. , 19 (2013), pp. 1251-1257
[4] S.H. Park, S.G. Hong, C.S. Lee, H.S. Kim, Korean J. Met. Mater. , 51 (2013), pp. 325-332
[5] H. Watanabe, T. Mukai, K. Suzuki, T. Shimizu, J. Jpn. Inst. Light Met. , 53 (2003), pp. 50-54
[6] J. Bohlen, S.B. Yi, J. Swiostek, D. Letzig, H.G. Brokmeier, K.U. Kainer, Scripta Mater. , 52 (2005), pp. 259-264
[7] J. Bohlen, M.R. Nurnberg, J.W. Senn, D. Letzig, S.R. Agnew, Acta Mater. , 55 (2007), pp. 2101-2112
[8] H.J. Mcqueen, M. Pekguleryuz, B.L. Mordike, F. Hehmann (Eds.), Magnesium Alloys and Their Application, DGM (1992), pp. 101-108
[9] K. Ohtoshi, M. Katsuta, J. Jpn. Inst. Light Met , 51 (2001), pp. 534-538
[10] G.S. Rao, Y.V.R.K. Prasad, Metall. Trans. A , 13 (1982), pp. 2219-2226
[11] M. Mabuchi, K. Ameyama, H. Iwasaki, K. Higashi, Acta Mater. , 47 (1999), pp. 2047-2057
[12] H.K. Lin, J.C. Huang, T.G. Langdon, Mater. Sci. Eng. A , 402 (2005), pp. 250-257
[13] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu, N. Saito, Scripta Mater. , 60 (2009), pp. 964-967
[14] X. Huang, K. Suzuki, N. Saito, Scripta Mater. , 60 (2009), pp. 651-654
[15] W.J. Kim, J.B. Lee, W.Y. Kim, H.T. Jeong, H.G. Jeong, Scripta Mater. , 56 (2007), pp. 309-312
[16] H. Watanabe, T. Mukai, K. Ishikawa, J. Mater. Sci. , 39 (2004), pp. 1477-1480
[17] W.J. Kim, J.D. Park, W.Y. Kim, J. Alloy. Compd. , 460 (2008), pp. 289-293
[18] X. Gong, S.B. Kang, S. Li, J.H. Cho, Mater. Des. , 30 (2009), pp. 3345-3350
[19] Y. Yoshida, L. Cisar, S. Kamado, Y. Kojima, Mater. Trans. , 44 (2003), pp. 468-475
[20] H. Watanabe, T. Mukai, K. Ishikawa, J. Mater. Process. Technol. , 182 (2007), pp. 644-647
[21] J.H. Cho, S.S. Jeong, H.W. Kim, S.B. Kang, Mater. Sci. Eng. A , 566 (2013), pp. 40-46
[22] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu, N. Saito, J. Alloy. Compd. , 457 (2008), pp. 408-412
[23] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu, N. Saito, J. Alloy. Compd. , 470 (2009), pp. 263-268
[24] Y.W. Tham, M.W. Fu, H.H. Hng, M.S. Yong, K.B. Lim, J. Mater. Process. Technol. , 192?193 (2007), pp. 575-581
[25] W.J. Kim, B.G. Hwang, M.J. Lee, Y.B. Park, J. Alloy. Compd. , 509 (2011), pp. 8510-8517
[26] L.L. Chang, J.H. Cho, S.B. Kang, J. Mater. Process. Technol. , 211 (2011), pp. 1527-1533
[27] X. Gong, H. Li, S.B. Kang, J.H. Cho, S. Li, Mater. Des. , 31 (2010), pp. 1581-1587
[28] W.J. Kim, H.W. Lee, S.J. Yoo, Y.B. Park, Mater. Sci. Eng. A , 528 (2011), pp. 874-879
[29] J.A. Del Valle, F. Carreno, O.A. Ruano, Acta Mater. , 54 (2006), pp. 4247-4259
[30] M.A. Meyers, O. Vohringer, V.A. Lubarda, Acta Mater. , 49 (2001), pp. 4025-4039
[31] L. Guo, Z. Chen, L. Gao, Mater. Sci. Eng. A , 528 (2011), pp. 8537-8545
[32] X. Huang, K. Suzuki, N. Saito, Mater. Sci. Eng. A , 508 (2009), pp. 226-233
[33] C.X. Huang, G. Yang, Y.L. Gao, S.D. Wu, Z.F. Zhang, Mater. Sci. Eng. A , 485 (2008), pp. 643-650
[34] D.H. Kang, D.W. Kim, S. Kim, G.T. Bae, K.H. Kim, N.J. Kim, Scripta Mater. , 61 (2009), pp. 768-771