Effect of Extrusion Strain Path on Microstructure and Properties of AZ31 Magnesium Alloy Sheet

doi:10.1007/s40195-015-0320-y

Abstract

Abstract:

The mechanical properties of AZ31 magnesium alloy sheets processed by different extrusion strain paths were examined in correlation with concurrent microstructure and texture evolution. The conventional extrusion (CE) and asymmetric extrusion (ASE) paths were performed on Mg alloy sheets. The textures at near surface and mid-layer of ASE sheets were various throughout sheet thickness direction as a result of extra asymmetric shear strain. This can stimulate the orientation of (0002) basal planes to incline approximately 12° toward the shear direction. Moreover, the basal texture of ASE sheet was weakened compared with CE one. Enhancing the ambient formability of extruded Mg alloy sheet fabricated by ASE path was accomplished by the tilted weak basal texture.

Key words: Mg alloy, Extrusion, Microstructure, Texture, Mechanical property, Formability

Qing-Shan Yang, Bin Jiang, Zu-Jian Yu, Qing-Wei Dai, Su-Qin Luo. Effect of Extrusion Strain Path on Microstructure and Properties of AZ31 Magnesium Alloy Sheet[J]. Acta Metallurgica Sinica (English Letters), 2015, 28(10): 1257-1263.

Figures/Tables 9

Fig. 1 Schematic diagram of the extrusion die: a conventional extrusion die; b asymmetric extrusion die

Fig. 2 FEM results of the effective strain a, the velocity b distribution of Mg alloy sheet during the ASE process

Fig. 3 Optical micrographs of AZ31 alloy at the shear zone: a top surface, b mid-layer, c bottom surface in the ASE dies during the hot extrusion process

Fig. 4 Optical micrographs of the CE sheet a, the ASE sheet at top surface b, mid-layer c, bottom surface d

Fig. 5 EBSD orientation maps of CE sheets, ASE sheets at top surface, mid-layer and bottom surface. Here, points a, b, c, d, e, f, g denote the c-axis correspond to the grains, respectively

Fig. 6 (0002) pole figures of AZ31 alloy sheets: a CE sheet; the ASE sheet at top surface b, mid-layer c, bottom surface d

Fig. 7 True stress-strain curves during tensile tests at different directions of CE and ASE sheets

Table 1 Results of the tensile tests carried out at the tensile directions of 0°, 45° and 90°

Sample	UTS (MPa)			YS (MPa)			E_u (%)			Average value
Sample	0°	45°	90°	0°	45°	90°	0°	45°	90°	UTS	YS	E_u	n	r
CE	332	323	331	161	148	167	15.4	22.1	19.0	327	156	19.7	0.29	1.64
ASE	315	326	344	150	125	136	16.4	23.7	22.1	328	134	21.5	0.34	1.00

Fig. 8 Secondary and the backscatter SEM fracture images of CE and ASE specimens

References 39

[1]	X.-H. Chen, L.-Z. Liu, J. Liu, F.-S. Pan, Acta Metall. Sin. (Engl. Lett.) 28, 492(2015)
[2]	A.A. Luo, J. Magn. Alloys 1, 2 (2013)
[3]	D. Sorgente, L.D. Scintilla, G. Palumbo, L. Tricarico, Int. J. Mater. Form. 3, 13(2009)
[4]	R.L. Doiphode, S.V.S. NarayanaMurty, N. Prabhu, B.P. Kashyap, J. Magn. Alloys 1, 169 (2013)
[5]	N. Stanford, J. Geng, Y.B. Chun, C.H.J. Davies, J.F. Nie, M.R. Barnett, Acta Mater. 60, 218(2012)
[6]	A. Hadadzadeh, M.A. Wells, J. Magn. Alloys 1, 101 (2013)
[7]	M. Nebebe, J. Bohlen, D. Steglich, D. Letzig, Int. J. Mater. Form. 2, 53(2009)
[8]	Q.S. Yang, B. Jiang, G.Y. Zhou, J.J. He, F.S. Pan, Mater. Sci. Technol. 30, 227(2014)
[9]	H. Zhang, W. Jin, J. Fan, W. Cheng, H. Jørgen Roven, B. Xu, H. Dong, Mater. Lett. 135, 31(2014)
[10]	H. Zhang, G. Huang, J. Fan, H. Jørgen Roven, F. Pan, B. Xu, Mater. Sci. Eng. A 608, 234 (2014)
[11]	D.L. Atwell, M.R. Barnett, W.B. Hutchinson, Mater. Sci. Eng. A 549, 1 (2012)
[12]	H. Pan, F. Pan, J. Peng, J. Gou, A. Tang, L. Wu, H. Dong, J. Alloy. Compd. 578, 493(2013)
[13]	D.-H. Hou, S.-M. Liang, R.-S. Chen, C. Dong, E.-H. Han, Acta Metall. Sin. (Engl. Lett.) 28, 115(2014)
[14]	S. Liu, G. Yang, W. Jie, Acta Metall. Sin. (Engl. Lett.) 27, 1134(2014)
[15]	R. Li, F. Pan, B. Jiang, Q. Yang, A. Tang, Mater. Des. 46, 922(2013)
[16]	A.S. Khan, A. Pandey, T. Gnäupel-Herold, R.K. Mishra, Int. J. Plast. 27, 688(2011)
[17]	L.W. Meyer, M. Hockauf, B. Zillmann, I. Schneider, Int. J. Mater. Form. 2, 61(2009)
[18]	S.R. Agnew, J.A. Horton, T.M. Lillo, D.W. Brown, Scr. Mater. 50, 377(2004)
[19]	J.-H. Cho, H.-W. Kim, S.-B. Kang, T.-S. Han, Acta Mater. 59, 5638(2011)
[20]	L. Shang, S. Yue, R. Verma, P. Krajewski, C. Galvani, E. Essadiqi, Mater. Sci. Eng. A 528, 3761 (2011)
[21]	W.X. Wu, L. Jin, Z.Y. Zhang, W.J. Ding, J. Dong, J. Alloys Compd. 585, 111(2014)
[22]	L.L. Chang, S.B. Kang, J.H. Cho, Mater. Des. 44, 144(2013)
[23]	W.J. Kim, S.I. Hong, J.M. Lee, S.H. Kim, Mater. Sci. Eng. A 559, 325 (2013)
[24]	W.J. Kim, Y.G. Lee, M.J. Lee, J.Y. Wang, Y.B. Park, Scr. Mater. 65, 1105(2011)
[25]	L.L. Chang, Y.N. Wang, X. Zhao, J.C. Huang, Mater. Sci. Eng. A 496, 512 (2008)
[26]	B. Song, R. Xin, G. Chen, X. Zhang, Q. Liu, Scr. Mater. 66, 1061(2012)
[27]	Y. Wang, S.B. Kang, J. Cho, J. Alloys Compd. 509, 704(2011)
[28]	H. Zhang, Y. Liu, J. Fan, H.J. Roven, W. Cheng, B. Xu, H. Dong, J. Alloys Compd. 615, 687(2014)
[29]	H. Zhang, G. Huang, J. Fan, H.J. Roven, B. Xu, H. Dong, J. Alloys Compd. 615, 302(2014)
[30]	Y.H. Ji, J.J. Park, Mater. Sci. Eng. A 499, 14 (2009)
[31]	X. Huang, K. Suzuki, Y. Chino, M. Mabuchi, J. Alloys Compd. 537, 80(2012)
[32]	O. Sabokpa, A. Zarei-Hanzaki, H.R. Abedi, Mater. Sci. Eng. A 550, 31 (2012)
[33]	D.G. Kim, K.M. Lee, J.S. Lee, Y.O. Yoon, H.T. Son, Mater. Lett. 75, 122(2012)
[34]	J.A. del Valle, F. Carreño, O.A. Ruano, Acta Mater. 54, 4247(2006)
[35]	R. Li, F. Pan, B. Jiang, H. Dong, Q. Yang, Mater. Sci. Eng. A 562, 33 (2013)
[36]	X. Huang, K. Suzuki, Y. Chino, J. Alloys Compd. 509, 4854(2011)
[37]	B. Wang, R. Xin, G. Huang, Q. Liu, Mater. Sci. Eng. A 534, 588 (2012)
[38]	K. Piao, J.K. Lee, J.H. Kim, H.Y. Kim, K. Chung, F. Barlat, R.H. Wagoner, Int. J. Plast 38, 27 (2012)
[39]	L. Lu, T. Liu, Y. Chen, Z. Wang, Mater. Charact. 67, 93(2012)