Mechanical Properties of a Spray-Cast Aluminum Alloy Processed by Severe Plastic Deformation

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Experiments were conducted to evaluate the mechanical properties of a spray-cast Al- 7034 alloy processed by severe plastic deformation. The alloy was received with an average grain size of ~2.1 μm and processed by equal-channel angular pressing (ECAP) at a temperature of 473 K to give a grain size of ~0.3 μm after 6 or 8 passes. Following ECAP, the mechanical properties were evaluated at room temperature (298 K) and at an elevated temperature of 673 K. In tensile testing at ambient temperature, the stress-strain curves show very short regions of strain hardening after ECAP and low values for the ultimate tensile strength by comparison with the unpressed alloy. This lack of strength is due to the high pressures imposed by ECAP and the consequent fragmentation and dissolution of the rod-like MgZn2 precipitates. It is shown that the strength may be restored by performing an appropriate ageing treatment after ECAP. Superplastic ductilities were recorded at a temperature of 673 K with tensile elongations exceeding 1000%. Careful inspection of the polished surfaces of samples pulled to fracture in the superplastic condition revealed the occurrence of extensive internal cavitation. Quantitative measurements showed the development of these internal cavities is consistent with conventional superplastic alloys.

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Materials Science Forum (Volumes 539-543)

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141-148

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March 2007

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© 2007 Trans Tech Publications Ltd. All Rights Reserved

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[1] R.Z. Valiev, R.K. Islamgaliev and I.V. Alexandrov, Prog. Mater. Sci. 45 (2000), p.103.

Google Scholar

[2] V.M. Segal, V.I. Reznikov, A.E. Drobyshevskiy and V.I. Kopylov, Russian Metall. 1 (1981), p.99.

Google Scholar

[3] M. Furukawa, Z. Horita, M. Nemoto and T.G. Langdon, J. Mater. Sci. 36 (2001), p.2835.

Google Scholar

[4] Z. Horita, T. Fujinami and T.G. Langdon, Mater. Sci. Eng. A318 (2001), p.34.

Google Scholar

[5] E.O. Hall, Proc. Roy. Soc. B 64 (1951), p.747.

Google Scholar

[6] N.J. Petch, J. Iron Steel Inst. 174 (1953), p.25.

Google Scholar

[7] Y. Iwahashi, J. Wang, Z. Horita, M. Nemoto and T.G. Langdon, Scripta Mater. 35 (1996), p.143.

Google Scholar

[8] M. Furukawa, Y. Iwahashi, Z. Horita, M. Nemoto and T.G. Langdon, Mater. Sci. Eng. A257 (1998), p.328.

Google Scholar

[9] C. Xu, W. Dixon, M. Furukawa, Z. Horita and T.G. Langdon, Mater. Lett. 57 (2003), p.3588.

Google Scholar

[10] C. Xu, M. Furukawa, Z. Horita and T.G. Langdon, Acta Mater. 51 (2003), p.6139.

Google Scholar

[11] M.J. Starink, N. Gao, M. Furukawa, Z. Horita, C. Xu and T.G. Langdon, Rev. Adv. Mater. Sci. 7 (2004), p.1.

Google Scholar

[12] C. Xu, M. Furukawa, Z. Horita and T.G. Langdon, Acta Mater. 53 (2005), p.749.

Google Scholar

[13] M. Kawasaki, C. Xu and T.G. Langdon, Acta Mater. 63 (2005), p.5353.

Google Scholar

[14] N. Gao, M.J. Starink, M. Furukawa, Z. Horita, C. Xu and T.G. Langdon, Mater. Sci. Eng. 410411 (2005), p.303.

Google Scholar

[15] S.C. Wang, M.J. Starink, N. Gao, C. Xu and T.G. Langdon, Rev. Adv. Mater. Sci. 10 (2005), p.249.

Google Scholar

[16] C. Xu, M. Furukawa, Z. Horita and T.G. Langdon, Mater. Sci. Forum 475-479 (2005), p.2949.

Google Scholar

[17] C. Xu and T.G. Langdon, Mater. Sci. Forum 503-504 (2006), p.77.

Google Scholar

[18] M. Kawasaki, C. Xu and T.G. Langdon, Mater. Sci. Forum 503-504 (2006), p.83.

Google Scholar

[19] N. Gao, M.J. Starink, M. Furukawa, Z. Horita, C. Xu and T.G. Langdon, Mater. Sci. Forum 503-504 (2006), p.275.

Google Scholar

[20] M.J. Starink, S.C. Wang, N. Gao, H.S. Ubhi, C. Xu and T.G. Langdon, Mater. Sci. Forum 503-504 (2006), p.937.

Google Scholar

[21] Z. Horita, T. Fujinami, M. Nemoto and T.G. Langdon, Metall. Mater. Trans. 31A (2000), p.691.

Google Scholar

[22] H. Hasegawa, S. Komura, A. Utsunomiya, Z. Horita, M. Furukawa, M. Nemoto and T.G. Langdon, Mater. Sci. Eng. A265 (1999), p.188.

Google Scholar

[23] S. Lee, A. Utsunomiya, H. Akamatsu, K. Neishi, M. Furukawa, Z. Horita and T.G. Langdon, Acta Mater. 50 (2002), p.553.

DOI: 10.1016/s1359-6454(01)00368-8

Google Scholar

[24] T.G. Langdon, Metall. Trans. 13A (1982), p.689.

Google Scholar

[25] S. Komura, Z. Horita, M. Furukawa, M. Nemoto and T.G. Langdon, Metall. Mater. Trans. 32A (2001), p.707.

Google Scholar

[26] K. Higashi, M. Mabuchi and T.G. Langdon, ISIJ Intl. 36 (1996), p.1423.

Google Scholar

[27] T.G. Langdon, Metal Sci. 16 (1982), p.175.

Google Scholar