Recrystallization and Precipitation of β-Mg17Al12 Phase of the Cold-Rolled Mg-9Al-1Zn Alloy Strip during Isothermal Annealing

Abstract:

Effect of isothermal annealing on the microstructure evolution of the cold-rolled Mg-9Al-1Zn alloy strip was investigated. It is found that the competition between the precipitation of β-Mg₁₇Al₁₂ phase and recrystallization of α-Mg matrix occur under the conditions of various annealing temperature and time. At a low annealing temperature (523K), the β-Mg₁₇Al₁₂ particles precipitate preferentially at locally high deformation area and grow into the lamellar-cluster with an increase in the annealing time, retarding the recrystallization of α-Mg matrix. With raising the annealing temperature (573~623K), both the precipitation of β-Mg₁₇Al₁₂ particles and recrystallization of α-Mg matrix take place. Both recrystallization and grain growth are prone to proceed without precipitation of β-Mg₁₇Al₁₂ particles when the annealing temperature is 673K. A mechanism for the competitive behavior between the precipitation of β-Mg₁₇Al₁₂ phase and recrystallization of α-Mg matrix at various annealing conditions is discussed.

• Periodical: Materials Science Forum (Volume 789)
• Pages: 336-343
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.789.336
• Online since: April 2014
• Authors: Yan Bin Jiang*, Zhi Hao Zhang, Lei Guan, Guo Yi Tang
• Keywords: Annealing, Magnesium Alloy, Precipitation, Recrystallization

References

[1] S. Schumann, H. Friedrich, Current and future use of magnesium in the automobile industry, Mater. Sci. Forum. 419-422(2003) 51-54.

DOI: 10.4028/www.scientific.net/msf.419-422.51

[2] Y. H. Peng:The application of magnesium alloy materials in auto industry, Automobile. Parts. 9(2008) 46-47.

[3] C. X. Zhang, P. L. Chen, H. J. Hai, A. J.Shi and S.K. Guan: Application and research progress of magnesium alloys in automobile industry, Foundry Technology. 29(2008) 531-535.

[4] D. Duly, J.P. Simon, Y. Brechet, On the competition between continuous and discontinuous precipitations in binary Mg Al alloys, Acta Metall Mater. 43(1995) 1012-1016.

DOI: 10.1016/0956-7151(95)90266-x

[5] D. Duly, M.C. Cheynet, Y. Brechet, Morphology and chemical nanoanalysis of discontinuous precipitation in Mg Al alloys—I. Regular growth, Acta Metall Mater. 42(1994) 3843-385.

DOI: 10.1016/0956-7151(94)90450-2

[6] Z.X. Wang, J.X. Xie, X.F. Liu, J.Y. Li, X.B. Zhang, F.S. Pan: Effects of deformation and aging on microstructure and mechanical property of AZ91 magnesium alloy, Acta Metall Sinica. 43 (2007) 920-924.

[7] P. Cotterill, P.R. Mould, Recrystallization and grain growth in metals, Surrey University Press, London, 1976.

[8] Y.B. Jiang, G.Y. Tang, C.H. Shek, Y.H. Zhu, Z.H. Xu, On the thermodynamics and kinetics of electropulsing induced dissolution of β-Mg17Al12 phase in an aged Mg–9Al–1Zn alloy, Acta Mater 57(2009) 4797-4808.

DOI: 10.1016/j.actamat.2009.06.044