Abstract
The minimum creep rate and microstructures of aged samples of Mg-Gd-Zr alloys, with and without alloying additions of Zn and/or Y, have been investigated in the present work. The creep tests were performed at 523 K (250 °C) and under 80 to 120 MPa, and the microstructures before and after creep tests were characterized using scanning electron microscopy, transmission electron microscopy, and the high-angle annular dark-field imaging technique. It is found that dislocation creep predominates in the steady-state creep stage for all alloys. The Mg-2.5Gd-0.1Zr (at. pct) alloy, strengthened by the β′ precipitates, has minimum creep rates in the range 1.0 × 10−8 to 3.8 × 10−8 s−1 under 80 to 120 MPa. The addition of 1.0 at. pct Zn to the Mg-2.5Gd-0.1Zr alloy reduces the 0.2 pct proof strength and increases the minimum creep rate, resulting from the formation of γ′ basal plates at the expense of β′ precipitates. The replacement of 1.0 at. pct Gd by Y in the Mg-2.5Gd-1.0Zn-0.1Zr alloy leads to a substantial reduction in the minimum creep rate, even though it does not cause much change to the 0.2 pct proof strength. The reduced minimum creep rate is attributed to a much lower diffusivity of Y atoms than Gd in the solid magnesium matrix. An increase in the Gd content from Mg-1.5Gd-1.0Y-1.0Zn-0.1Zr to Mg-2.5Gd-1.0Y-1.0Zn-0.1Zr leads to a denser distribution of precipitates, a higher 0.2 pct proof strength, and a further reduction in the minimum creep rate.
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References
L.L. Rokhlin: Magnesium Alloys Containing Rare Earth Metals, Taylor & Francis Ltd, London, 2003.
I.J. Polmear: Light Alloys, 4th ed., Elsevier/Butterworth-Heinemann, Oxford, 2006.
B.L. Mordike: Mater. Sci. Eng. A, 2002, vol. 324, pp. 103–112.
K. Maruyama, M. Suzuki and H. Sato: Metall. Mater. Trans. A, 2002, vol. 33A, pp. 875–82.
G.W. Lorimer, P.J. Apps, H. Karimzadeh and J.F. King: Mater. Sci. Forum, 2003, vol. 419–422, pp. 279-84.
I.A. Anyanwu, S. Kamado and Y. Kojima: Mater. Trans., 2001, vol. 42, pp. 1206–11.
B. Smola, I. Stulíková, J. Pelcová and B.L. Mordike: J. Alloys Compd., 2004, vol. 378, pp. 196–201.
Y. Kawamura and M. Yamasaki: Mater. Trans., 2007, vol. 48, pp. 2986–92.
I.A. Anyanwu, S. Kamado and Y. Kojima: Mater. Trans., 2001, vol. 7, pp. 1212–18.
J.F. Nie, X. Gao and S.M. Zhu: Scripta Mater., 2005, vol. 53, pp. 1049–53.
D.D. Yin, Q.D. Wang, C.J. Boehlert and V. Janik: Metall. Mater. Trans. A, 2012, vol. 43A, pp. 3338–50.
S.M. He, X.Q. Zeng, L.M. Peng, X. Gao, J.F. Nie and W.J. Ding: J. Alloys Compd., 2007, vol. 427, pp. 316–23.
K. Yamada, Y. Okubo, M. Shiono, H. Watanabe, S. Kamado and Y. Kojima: Mater. Trans., 2006, vol. 47, pp. 1066–70.
L. Wang, Q. Peng, J. Yang, D. Fang, Y. Wu, H. Liu, J. Meng and H. Zhang: Mater. Sci. Forum, 2007, vol. 539–543, pp. 1719–22.
Y. Kawamura, K. Hayashi, A. Inoue and T. Masumoto: Mater. Trans., 2001, vol. 42, pp. 1172–76.
M. Yamasaki, T. Anan, S. Yoshimoto and Y. Kawamura: Scripta Mater., 2005, vol. 53, pp. 799–803.
K. Hagihara, A. Kinoshita, Y. Sugino, M. Yamasaki, Y. Kawamura, H.Y. Yasuda and Y. Umakoshi: Acta Mater., 2010, vol. 58, pp. 6282–93.
V. Janik, D.D. Yin, Q.D. Wang, S.M. He, C.J. Chen, Z. Chen and C.J. Boehlert: Mater. Sci. Eng. A, 2011, vol. 528, pp. 3105–12.
F.R.N. Nabarro and H.L. de Villiers: The Physics of Creep, Taylor & Francis Ltd, London, 1995.
J. Čadek: Creep in Metallic Materials, Elsevier, Amsterdam, 1988.
F.A. Mohamed and T.G. Langdon: Acta Metall., 1974, vol. 22, pp. 779–88.
J. Weertman: J. Appl. Phys., 1955, vol. 26, pp. 1213–17.
X. Gao, S.M. He, X.Q. Zeng, L.M. Peng, W.J. Ding and J.F. Nie: Mater. Sci. Eng. A, 2006, vol. 431, pp. 322–27.
T. Honma, T. Ohkubo, S. Kamado and K. Hono: Acta Mater., 2007, vol. 55, pp. 4137–50.
T. Honma, T. Ohkubo, K. Hono and S. Kamado: Mater. Sci. Eng. A, 2005, vol. 395, pp. 301–06.
J.F. Nie, K. Oh-ishi, X. Gao and K. Hono: Acta Mater., 2008, vol. 56, pp. 6061–76.
J.F. Nie: Metall. Mater. Trans. A, 2012, vol. 43, pp. 3891–3939.
M. Yamasaki, M. Sasaki, M. Nishijima, K. Hiraga and Y. Kawamura: Acta Mater., 2007, vol. 55, pp. 6798–6805.
D. Egusa and E. Abe: Acta Mater., 2012, vol. 60, pp. 166–78.
J.G. Wang, L.M. Hsiung, T.G. Nieh and M. Mabuchi: Mater. Sci. Eng. A, 2001, vol. 315, pp. 81–88.
R.A. Khosrhoshahi, R. Pilkington, G.W. Lorimer, P. Lyon, and H. Karimzadeh: in The 3rd International Magnesium Conference, G.W. Lorimer, ed., The Institute of Materials, Manchester, 1996, pp. 241–56.
H. Karimzadeh, J.M. Worrall, R. Pilkington, and G.W. Lorimer: in Magnesium Technology, C. Baker, G.W. Lorimer, and W. Unsworth, eds., Institute of Metals, London, 1987, pp. 138–41.
Y.M. Zhu, M. Weyland, A.J. Morton, K. Oh-ishi, K. Hono and J.F. Nie: Scripta Mater., 2009, vol. 60, pp. 980–83.
Y.M. Zhu, A.J. Morton and J.F. Nie: Acta Mater., 2010, vol. 58, pp. 2936–47.
Y.M. Zhu, A.J. Morton, M. Weyland and J.F. Nie: Acta Mater., 2010, vol. 58, pp. 464–75.
S.M. Zhu, M.A. Gibson, M.A. Easton and J.F. Nie: Scripta Mater., 2010, vol. 63, pp. 698–703.
S.M. Zhu, J.F. Nie, M.A. Gibson, M.A. Easton and P. Bakke: Metall. Mater. Trans. A, 2012, vol. 43A, pp. 4137–44.
A. Suzuki, N.D. Saddock, J.R. TerBush, B.R. Powell, J.W. Jones and T.M. Pollock: Metall. Mater. Trans. A, 2008, vol. 39A, pp. 696-702.
J.R. TerBush, A. Suzuki, N.D. Saddock, J.W. Jones and T.M. Pollock: Scripta Mater., 2008, vol. 58, pp. 914–17.
I.P. Moreno, T.K. Nandy, J.W. Jones, J.E. Allison and T.M. Pollock: Scripta Mater., 2003, vol. 48, pp. 1029–34.
N.D. Saddock, A. Suzuki, J.W. Jones and T.M. Pollock: Scripta Mater., 2010, vol. 63, pp. 692–97.
B. Burton and B.D. Bastow: Acta Metall., 1973, vol. 21, pp. 13–20.
J.F. Nie, M.A. Easton, T.B. Abbott, S.M. Zhu, and M.A. Gibson: in The 8th International Conference on Magnesium Alloys and their Applications, K.U. Kainer, ed., Wiley, Weimar, 2009, pp. 89–95.
G. Neumann and C. Tuijin: Self-diffusion and Impurity Diffusion in Pure Metals: Handbook of Experimental Data, Pergamon Press, Aachen, 2008.
J.F. Nie: Scripta Mater., 2003, vol. 48, pp. 1009–15.
W.D. Nix and B. Ilschner: in The 5th International Conference on the Strength of Metals and Alloys, P. Haasen, V. Gerold, and G. Kostorz, eds., Pergamon Press, Aachen, 1979, pp. 1503–30.
G.B. Gibbs: Philos. Mag., 1971, vol. 23, pp. 771–80.
Acknowledgments
This research was funded by NSFC (Nos. 50971089 and 51304135), Shanghai Jiao Tong University, and the Australia Research Council. The authors gratefully acknowledge the access to the facilities of the Monash Centre for Electron Microscopy (MCEM). The authors would like to thank the staff of the MCEM for their training, and Dr. Suming Zhu and Hong Liu (Monash University) for helpful discussions with them.
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Manuscript submitted December 5, 2013.
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Xu, WF., Zhang, Y., TerBush, J.R. et al. Effects of Alloying Elements on Creep Properties of Mg-Gd-Zr Alloys. Metall Mater Trans A 45, 4103–4116 (2014). https://doi.org/10.1007/s11661-014-2335-9
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DOI: https://doi.org/10.1007/s11661-014-2335-9