The effects of pulse current on the superplastic deformation of AZ31 magnesium alloy with different microstructures were examined. The results of TEM analysis showed that the dislocation movement was mainly glide, and the dislocation lines were approximate parallel with few dislocation tangles observed, which indicated that the dislocation movement was promoted during he deformation, and therefore the formability of the coarse-grained AZ31 magnesium alloy was enhanced by the pulse current. This effect was also indicated by the asymmetrical contour of the free bulging sample, which was observed in the unidirectional pulses auxiliary equi-biaxial tensile test of coarse-grained alloy. In addition, the phenomenon of the restrained cavity growth caused by the thermoelectrical effect of the pulse current was discovered and studied.
CHAO
,
KAIFENG -Zhang
. Promotion mechanism of the pulse current on the superplastic deformation of AZ31 magnesium alloy[J]. Acta Metallurgica Sinica (English Letters), 2012
, 25(2)
: 153
-159
.
DOI: 10.11890/1006-7191-122-153
[1] Y.D. Yu, K.F. Zhang, H.R. Zheng and D.M.Jiang, Acta Metall Sin(Engl Lett) 17(3) (2004) 295
[2] X. Wu and Y. Liu, Scr Mater 46 (2002) 269
[3] M.R. Barnett, S. Jacob, B.F. Gerard and J.G. Mullins, Scr Mater 59 (2008) 1035
[4] C.P. Zhang, K.F. Zhang and G.F. Wang, Intermetallics 18 (2010) 834
[5] J. Yanagimoto and R. Izumi, J Mater Process Technol 209 (2009) 3060
[6] K. Mori, S. Maki and Y. Tanaka, Ann CIRP 54 (2005) 209
[7] H. Watanabe, H. Tsutsui, T. Mukai, M. Kohzu, S. Tanabe and K. Higashi, Int J Plast 17 (2001) 387
[8] Y.N. Yu and W.M. Mao, The Structure of Material (Metallurgical Industry Press, Beijing, 2001) p.210 (in Chinese)
[9] X.H. Dong, D.F. Hou, Y. Li and X.Z. Wang, Met Form Technol 22(1) (2004) 37 (in Chinese)
[10] W.B. Lagow, I.M. Robertson, M. Jouiad, D.H. Lassila, T.C. Lee and H.K. Birnbaum, Mater Sci Eng A 309-310 (2001)445
[11] S.W. Chung, K. Higashi and W.J. Kim, Mater Sci Eng A 372 (2004) 15
[12] T.J.C. Liu, Theor Appl Fract Mech 49 (2008)171
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