The Effect of Temperature on Microstructure Evolution in a 7055 Aluminum Alloy Subjected to ECAP

Abstract:

Grain refinement taking place in a commercial 7055 aluminum alloy under equal channel angular pressing (ECAP) was examined in the temperature interval 250375°C. It was shown that the formation of recrystallized grains occurs through continuous dynamic recrystallization (CDRX). At 250°C, a low rate of dynamic recovery and high volume fraction of second phase particles provide the rapid formation of stable three-dimensional arrays of low-angle boundaries and their gradual transformation into high-angle boundaries. Increasing temperature leads an increase in the average crystallite size produced by ECAP from 0.7 μm at 250°C to 1.3 μm at 375°C. The effect of temperature on CDRX kinetic is discussed.

• Periodical: Materials Science Forum (Volumes 715-716)
• Pages: 317-322
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.715-716.317
• Online since: April 2012
• Authors: Ilya Nikulin, Rustam Kaibyshev
• Keywords: Aluminium Alloy, Continuous Dynamic Recrystallization, Equal Channel Angular Extrusion (ECAE), Submicrocrystalline Structure

References

[1] I. N. Fridlyander: Met. Sci. Heat Treat., 1 (2001), p.5.

[2] R.Z. Valiev, T.G. Langdon: Prog. Mater. Sci., 51 (2006), p.881.

[3] R. Kaibyshev, T. Sakai, I. Nikulin, F. Musin, A. Goloborodko: Mater. Sci. Tech., 19 (2003), p.1491.

[4] I. Nikulin, Y. Motohashi, R. Kaibyshev: Mater. Sci. Forum Vol. 574-586 (2008), p.691.

[5] Y.C. Chen, Y.Y. Huang, C.P. Chang, P.W. Kao: Acta Mater. 51 (2003), (2005).

[6] A. Goloborodko, O. Sitdikov, R. Kaibyshev, H. Miura, T. Sakai: Mater. Sci. Eng. A381 (2004), p.121.

[7] A. Yamashita, D. Yamaguchi, Z. Horita, T.G. Langdon: Mater. Sci. Eng. A287 (2000), p.100.

[8] A. Gholinia, F.J. Humphreys, P.B. Prangnell: Acta Mater 50 (2002), p.4461.

[9] F.J. Humphreys, P.B. Prangnell, J.R. Bowen, A. Gholinia, C. Harris: Phil. Trans. R. Soc. Lond., A357 (1999), p.1663.

[10] P.J. Apps, J.R. Bowen, P.B. Prangnell: Acta Mater., 51 (2003), p.2811.

[11] F.J. Humphreys, M. Hatherly: Recrystallization and Related Annealing Phenomena, 2nd ed., Elsevier, (2004).

[12] M. Ferry, N.E. Hamilton, F.J. Humphreys: Acta Mater. V. 53 (2005), 1097.

[13] R. Kaibyshev, K. Shipilova, F. Musin, Y. Motohashi: Mater. Sci. Eng. A396 (2005), p.341.

[14] O. Sitdikov, T. Sakai, E. Avtokratova, R. Kaibyshev, K. Tsuzaki, Y. Watanabe: Acta Mater. 56 (2008), p.821.

DOI: 10.1016/j.actamat.2007.10.029

[15] M. Biberger, W. Blum: Phil. Mag. A 65 (1992), p.757.

[16] M. Biberger, W. Blum: Phil. Mag. A 66 (1992), p.27.

[17] W. Muller, M. Biberger, W. Blum: Phil. Mag. A66 (1992), p.717.