Microstructure and Mechanical Properties of Ultra-Fine Grain AZ80 Alloy Processed by Back Pressure Equal Channel Angular Pressing

Abstract:

Experiments were conducted on AZ80 magnesium alloy by using a procedure of back pressure equal-channel angular pressing (BP-ECAP) in order to achieve submicron grain size. Microstructure was effectively refined by BP-ECAP. The gain size was found around 100~500 nm after 4 passes using both route A and route Bc at pressing temperatures of 200°C and 150 °C. The grain size was much finer in comparison with the same alloy but received conventional procedure of ECAP without back pressure, which maintains around 2~3 μm after 8 passes at relatively high temperatures. Compression test results showed the yield strength increased with increasing applied pass. In addition, the samples processed using route A had a increasing of yield strength more obvious than that in samples processed using route Bc. The highest yield strength from the sample pressed by route A at 150 °C was more than twice of the yield strength in the solution-treated and forged condition.

• Periodical: Materials Science Forum (Volumes 667-669)
• Pages: 547-552
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.667-669.547
• Online since: December 2010
• Authors: Nian Xian Zhang, Hua Ding, Ji Zhong Li, Xiao Lin Wu, Ying Long Li, Kenong Xia
• Keywords: AZ80 Magnesium Alloy, Back Pressure, Equal-Channel Angular Pressing (ECAP), Grain Size, Texture

References

[1] R.Z. Valiev. Nature Mater. Vol. 3 (2004), p.511.

[2] R.Z. Valiev, R.R. Mulyukov, V.V. Ovchinnikov and V.A. Shabashov. Scr. Metall. Mater. Vol. 25 (1991), p.841.

[3] K.Y. Mulyukov, S.B. Khaphizov and R.Z. Valiev. Phys. Stat. Sol. A Vol. 133 (1992), p.447.

[4] N.A. Akhmadeev, N.P. Kobelev, R.R. Mulyukov, Y.M. Soifer and R.Z. Valiev. Acta Metall. Mater. Vol. 41 (1993), p.1041.

[5] R.Z. Valiev and T.G. Langdon. Prog. Mater. Sci. Vol. 51 (2006), p.881.

[6] W.J. Kim, S.I. Hong, Y.S. Kim, S.H. Min, H.T. Jeong and J.D. Lee. Acta Mater. Vol. 51 (2003), p.3293.

[7] T.G. Langdon. Mater. Sci. Eng. A Vol. 174. (1994), p.225.

[8] N.A. Krasilnikov. Russian Metall Vol. 3 (2005), p.35.

[9] G.I. Raab, N.A. Krasilnikov and R.Z. Valiev. Physics and Engineering of High Pressures Vol. 10 (2000), p.73.

[10] R. Lapovok J. Mater. Sci. Vol. 40 (2005), p.341.

[11] R. Lapovok . Russian Metall Vol. 1 (2004), p.44.

[12] W. Unsworth, J.F. King and S.L. Bradshaw. US Patent 4, 401, 621. (1983).

[13] M.F. Ashby. Phil. Mag. Vol. 21 (1970), p.399.

[14] S.I. Hong, G.T. Gray III and J.J. Lewandowski. Acta Metall. Mater. Vol. 41 (1993), p.2337.

[15] T. Al-Samman and G. Gottstein. Mater. Sci. Eng. A Vol. 490 (2008), p.411.

[16] E.A. Ball and P.B. Prangnell. Scr. Metall. Mater. Vol. 31 (1994), p.111.

[17] D.L. Yin, J.T. Wang, J.Q. Liu and X.J. Zhao. Alloys Comp. Vol. 478 (2009), p.789.

[18] E.W. Kelley and W. F Hosford. Trans. Metall. Soc. AIME Vol. 242 (1968), p.5.

[19] T. Al-Samman and G. Gottstein. Mater. Sci. Eng. A Vol. 488 (2008), p.406.