Effect of Additional Shear Stress on Microstructure Evolution of AZ31 Sheet by Differential Speed Rolling

Abstract:

Asymmetric rolling of deformed magnesium alloys sheet can accelerate refine the grain size, reduce the basal texture, and improve the subsequent formability. This happens because the additional shear stress and strain are introduced during the differential speed rolling. This paper investigates the relationship of shear stress and microstructure evolution by the experiment in conjunction with the FEM (Finite Element Method) simulation. The differential speed ratio (1, 1.2 and 1.5) and rolling reduction (8% and 15%) were executed at room temperature. The additional shear strain field is simulated for corresponding asymmetric rolling conditions. The results showed that the additional shear stress and strain were the essential influence factors of microstructure evolution and formability of AZ31 sheet for the differential speed rolling. It is helpful in enhancing and improving the formability of rolled magnesium alloys.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 433-438
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.433
• Online since: April 2015
• Authors: Yu Teng Shen, Xin Ran Ou, Ze Jun Chen*
• Keywords: AZ31, Microstructure, Numerical Simulation, Shear Stress, Speed Ratio

References

[1] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu, N. Saito, Microstructure and texture of Mg-Al-Zn alloy processed by differential speed rolling. J. Alloys Compd. 457 (2008) 408-412.

DOI: 10.1016/j.jallcom.2007.02.144

[2] B.L. Mordike, T. Ebert, Magnesium properties-applications-potential. Mater. Sci. Eng. A. 302 (2001) 37-45.

[3] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu. Mechanical properties of Mg-Al-Zn alloy with a tilted basal texture obtained by differential speed rolling. Mater. Sci. Eng. A. 488 (2008) 214-220.

DOI: 10.1016/j.msea.2007.11.029

[4] X. Huang, K. Suzuki, A. Watazu, N. Saito, Effects of thickness reduction per pass on microstructure and texture of Mg-3Al-1Zn alloy sheet processed by differential speed rolling. Scripta Mater. 60(2009) 964-967.

DOI: 10.1016/j.scriptamat.2009.02.022

[5] L.L. Chang, J.H. Cho, S.B. Kang, Microstructure and mechanical properties of AM31 magnesium alloys processed by differential speed rolling. J. Mater Process Technol. 211 (2011) 1527-1533.

DOI: 10.1016/j.jmatprotec.2011.04.003

[6] X.B. Gong, S.B. Kang, S.Y. Li, J.H. Cho, Enhanced plasticity of twin-roll cast ZK60 magnesium alloy through differential speed rolling. Mater. Des. 30 (2009) 3345-3350.

DOI: 10.1016/j.matdes.2009.03.040

[7] H.G. Jeong, Y.G. Jeong, W.J. Kim, Microstructure and superplasticity of AZ31 sheet fabricated by differential speed rolling. J. Alloys Compd. 483 (2009) 279-282.

DOI: 10.1016/j.jallcom.2008.08.130

[8] W.J. Kim, J.B. Lee, W.Y. Kim, H.T. Jeong, H.G. Jeong, Microstructure and mechanical properties of Mg-Al-Zn alloy sheets severely deformed by asymmetrical rolling. Scripta Mater. 56 (2007) 309-312.

DOI: 10.1016/j.scriptamat.2006.09.034

[9] Y.H. Ji, J.J. Park, W.J. Kim, Finite element analysis of severe deformation in Mg-3Al-1Zn sheet through differential-speed rolling with a high speed ratio. Mater. Sci. Eng. A. 454 (2007) 570-574.

DOI: 10.1016/j.msea.2006.11.076

[10] H. Watanabe, T. Mukai, K. Ishikawa, Effect of temperature of differential speed rolling on room temperature mechanical properties and texture in an AZ31 magnesium alloy. J. Mater Process Technol. 182 (2007) 644-647.

DOI: 10.1016/j.jmatprotec.2006.08.010

[11] X. Huang, K. Suzuki, A. Watazu, I. Shigematsu, N. Saito, Improvement of formability of Mg-Al-Zn alloy sheet at low temperatures using differential speed rolling. J. Alloys Compd. 457 (2008) 408-412.

DOI: 10.1016/j.jallcom.2008.02.029

[12] W.J. Kim, J.B. Lee, W.Y. Kim, H.T. Jeong, Realization of low-temperature superplasticity in Mg-Al-Zn alloy sheets processed by differential speed rolling. Scripta Mater. 57 (2008) 755-758.

DOI: 10.1016/j.scriptamat.2007.06.020

[13] W.J. Kim, J.B. Lee, W.Y. Kim, Effect of differential speed rolling on microstructure and mechanical properties of an AZ91 magnesium alloy. J. Alloys Compd. 460 (2008) 289-293.

DOI: 10.1016/j.jallcom.2007.06.050

[14] X. Huang, Microstructure and mechanical properties of AZ80 magnesium alloy sheet processed by differential speed rolling. Mater. Sci. Eng. A. 508 (2009) 226-233.

DOI: 10.1016/j.msea.2008.12.052

[15] J.B. Lee, Grain refinement and texture evolution in AZ31 Mg alloys sheet processed by differential speed rolling. Mater. Sci. Eng. B. 161 (2009) 166-169.

DOI: 10.1016/j.mseb.2009.02.021