Effect of Cold Deformation on Microstructure and Mechanical Properties of Mg-8Gd-3Y-0.5Zr Alloy

Abstract:

Pre-cold rolling with the reduction of 15% was employed on Mg-8Gd-3Y-0.5Zr (wt.%) (GW83K) alloy in different initial states: as-extruded (state 1) and extruded followed by annealing (state 2) with the aim to investigate the effects on microstructure and mechanical properties. Microstructure observation revealed that there are more amounts of mechanical twins in the alloy in state 2 than that of the alloy in state 1 after cold rolling, which indicates the different deformation mechanisms. Further investigation through EBSD has elucidated the grain boundary structure and types of twins in the alloys. Pre-cold deformation greatly promotes the age hardening response and the peak aging time at 200°C was found to be nearly 12h for the alloy in both state 1 and state 2, which were about 24h and 80h less than that of their non-deformed counterparts, respectively. Tensile tests at temperatures lower than 250°C showed that the alloy in state 1 has a predominant mechanical property than that of the alloy in state 2, while at 300°C, it displayed a reverse tendency.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 1297-1302
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.1297
• Online since: January 2012
• Authors: De Jiang Li, Xiao Qin Zeng, Xin Su, Yan Cai Xie, Wen Jiang Ding
• Keywords: Cold Deformation, EBSD, Mechanical Property, Mg-Gd-Y-Zr Alloy, Microstructure

References

[1] L.L. Rokhlin, Magnesium Alloys Containing Rear Earth Metals, Taylor and Francis, London, (2003).

[2] S. Kamado, Y. Kojima, R. Ninomiya, K. Kubota, Proceedings of the 3th Inter. Mg conference, 1996, Institute of Materials, Manchester, UK, 1997, 327-342.

[3] S.M. He, X.Q. Zeng, L.M. Peng, X. Gao, J.F. Nie, W.J. Ding, J. Alloys Compd. 427(2007), 316-323.

[4] He Shangming, Doctoral Thesis (In Chinese), Shanghai Jiao Tong University, Shanghai, 2007, p.89.

[5] S.M. He, X.Q. Zeng, L.M. Peng, X. Gao, J.F. Nie, W.J. Ding, J. Alloys Compd. 421(2006), 309-313.

[6] Z.H. Ismail, Scripta Metall. 32(1995), 457-462.

[7] N. Unlu, B.M. Gable, G.J. Shiflet, E.A. Strarke, Metall. Mater. Trans. A 34(2003), 2757-2769.

[8] R. Markandeya, S. Nagarjuna, D.S. Sarma, Mater. Sci. Eng. A 404(2005), 305-313.

[9] M.F. Ashby, Philos. Mag. 21 (1970) 399.

[10] J. Koike, Metall. Mater. Trans. a-Phys. Metall. Mater. Sci. 36A (2005) 1689.

[11] Li Dejiang, Doctoral Thesis(In Chinese), Shanghai Jiao Tong University, Shanghai, 2010, p.88.

[12] Lan Jiang, John J. Jonas, Alan A. Luo, Anil K. Sachdev, Stephane Godet, Scripta Mater., 54 (2006) 771-775.

[13] Yu Kun, Li Wenxian, Wang Richu, Trans. Nonferrous Metals Soc. of China, 15(7) (2005), 1081-1086 (In Chinese).

[14] J.A. del Valle, F. Carreno, O.A. Ruano, Acta Mater., (2006) 4247-4259.

[15] Valerie Randle, Gregory Owen, Acta Mater., 54(2006), 1777-1783.