Effect of Plastic Deformation on the Mechanical Properties and Microstructure of Homogenized AZ80 Magnesium Alloy

Abstract:

In the present research, the influences of different extrusion ratios (15, 30, 45, 60, and 75) and extrusion temperatures (300°C, 330°C, 360°C, 390°C, 420°C) on the mechanical properties and microstructure of homogenized AZ80 alloy have been investigated through the tensile tests and via metallographic microscope observation. The results show that the alloy’s grain is small and small amounts of black hard and brittle second-phase β (Mg17Al12) are precipitated uniformly along the grain boundary causing the gradual increase of the alloy’s tensile strength at 330°C. When the extrusion temperature is up to 390°C, the grain size increases significantly, but the second phase precipitation along grain boundaries transforms into continuous and uniform-distribution precipitation within the grain. In this case, when the extrusion ratio is 60, the alloy’s tensile strength reaches its peak 390Mpa. As the extrusion temperature increases, inhomogeneous precipitation of the second-phase along grain boundaries increases, causing the decrease of the alloy’s strength. At the same temperature, the tensile strength increases firstly and then decreases as extrusion ratio increases. With the gradual increase of the refinement grain, the dispersed precipitates increase and the alloy’s tensile strength and plasticity reach their peaks when the extrusion temperature is 390°C. As the grain grows, the second phase becomes inhomogeneous distribution, and the alloy’s strength and plasticity gradually decrease.

• Periodical: Advanced Materials Research (Volumes 139-141)
• Pages: 180-184
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.139-141.180
• Online since: October 2010
• Authors: Yong Xue, Zhi Min Zhang, Li Hui Lang
• Keywords: AZ80 Magnesium Alloy, Mechanical Property, Microstructure, Plastic Deformation

References

[1] H.T. Zhou, C.J. Ma, X.Q. Zeng, W.J. Ding: Materials Review, Vol. 17-11 (2003), p.16.

[2] T. Homma, N. Kunito: Scripta Materialia, Vol. 61 (2009), p.644.

[3] Z.H. Chen, F.Y. Xu, D.F. Fu, W.J. Xia: Chemical Industry and Engineering Progress, Vol. 25-2 (2006), p.140.

[4] C.M. Liu: The Chinese Journal of Nonferrous Metals, Vol. 16-1 (2006), p.1.

[5] J.M. Zhang, B.L. Jiang, Z.H. Wang, P.J. Xia, K.C. Ge: Special Casting & Nonferrous alloys, Vol. 1 (2008), p.60.

[6] I.A. Yakubtsov, B. J. Diaka: Materials Science and Engineering A, Vol. 496 (2008), p.247.

[7] Q. Guo, H.G. Yan, Z.H. Chen, H. Zhang: Journal of Plasticity Engineering, Vol. 7 (2006), p.739.

[8] P. Zhang, J. Lindemann: Scripta Materialia, Vol. 52 (2005), p.485.

[9] Y. Uematsu, K. Tokaji, M. Kamakura, K. Uchida: Materials Science and Engineering, Vol. 434 (2006), p.131.

[10] M. Shahzad, L. Wagner: Materials Science and Engineering A, Vol. 506 (2009), p.141.