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Cavity growth rate in superplastic 5083 Al and AZ31 Mg alloys

Published online by Cambridge University Press:  01 November 2004

Yasumasa Chino
Affiliation:
Materials Research Institute for Sustainable Development, National Institute of Advanced Industrial Science and Technology, Moriyama-ku, Nagoya 463-8560, Japan
Hajime Iwasaki
Affiliation:
Materials Research Institute for Sustainable Development, National Institute of Advanced Industrial Science and Technology, Moriyama-ku, Nagoya 463-8560, Japan
Mamoru Mabuchi
Affiliation:
Department of Energy Science and Technology, Kyoto University, Kyoto 606-8501, Japan
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Abstract

The plasticity-controlled growth rate of cavities during superplastic deformationwas statistically investigated for 5083 Al alloy and AZ31 Mg alloy. When the cavity growth rate was evaluated on the basis of macroscopic strain calculated using the displacement of the specimen, the growth rate for the Al alloy was larger than thatfor the Mg alloy. However, the growth rate of the Al alloy was in agreement withthat of the Mg alloy when the cavity growth rate was evaluated on the basis of the microscopic strain due to grain boundary sliding. The results obtained lead to two conclusions: (i) the rate of cavity growth is not affected by the kind of materials,that is, the nature of the grain boundary, and (ii) the microscopic strain due to grain boundary sliding should be used to evaluate exactly the rate of cavity growth for superplastic deformation.

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Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1Pilling, J. and Ridley, N.: Superplasticity in Crystalline Solids (The Institute of Metals, London, U.K.,1989), p. 102Google Scholar
2Langdon, T.G.: Fracture processes in superplastic flow. Met. Sci. 16, 175 (1982).CrossRefGoogle Scholar
3Gifkins, R.C.: Grain rearrangements during superplastic deformation. J. Mater. Sci. 13, 1926 (1978).CrossRefGoogle Scholar
4Valiev, R.Z. and Kaibyshev, O.A.: On the quantitative evaluation of superplastic flow mechanisms. Acta Metall. 12, 2121 (1983).CrossRefGoogle Scholar
5Langdon, T.G.: An investigation of the strain contributed by grain boundary sliding in superplasticity. Mater. Sci. Eng. A 174, 225 (1994).Google Scholar
6Hull, D. and Rimmer, D.E.: The growth of grain-boundary voids under stress. Philos. Mag. 4, 673 (1959).Google Scholar
7Beere, W. and Speight, M.V.: Creep cavitation by vacancy diffusion in plastically deforming solid. Met. Sci. 12, 172 (1978).CrossRefGoogle Scholar
8Hancock, J.W.: Creep cavitation without a vacancy flux. Met. Sci. 10, 319 (1976).CrossRefGoogle Scholar
9Edward, G.H. and Ashby, M.F.: Intergranular fracture during power-law creep. Acta Metall. 27, 1505 (1979).Google Scholar
10Chokshi, A.H.: The development of cavity growth maps for superplastic materials. J. Mater. Sci. 21, 2073 (1986).Google Scholar
11Miller, D.A. and Langdon, T.G.: Cavitation in a superplastic Al-Zn-Mg alloy. Trans. JIM 21, 123 (1980).Google Scholar
12Armstrong, R., Codd, I., Douthwaite, R.M. and Petch, N.J.: The plastic deformation of polycrystalline aggregates. Philos. Mag. 7, 45 (1962).CrossRefGoogle Scholar
13Kubota, K., Mabuchi, M. and Higashi, K.: Processing and mechanical properties of fine-grained magnesium alloys. J. Mater. Sci. 34, 2255 (1999).CrossRefGoogle Scholar
14Mabuchi, M., Chino, Y. and Iwasaki, H.: Tensile properties at room temperature to 823 K of Mg-4Y-3RE alloy. Mater. Trans. 43, 2063 (2002).Google Scholar
15Mabuchi, M. and Higashi, K.: Strengthening mechanisms of Mg-Si alloys. Acta Mater. 44, 4611 (1996).Google Scholar
16Pilling, J. and Ridley, N.: Superplasticity in Crystalline Solids (The Institute of Metals, London, U.K.,1989), p. 48Google Scholar
17Langdon, T.G.: The mechanical properties of superplastic materials. Metall. Trans. A 13A, 689 (1982).CrossRefGoogle Scholar
18Arieli, A. and Mukherjee, A.K.: The rate-controlling deformation mechanisms in superplasticity—a critical assessment. Metall. Trans. A 13A, 717 (1982).CrossRefGoogle Scholar
19Bampton, C.C. and Edington, J.W.: Microstructural observation of superplastic cavitation in fine grained 7475-Al. Metall. Trans. A A13, 1721 (1982).CrossRefGoogle Scholar
20Frost, H.J. and Ashby, M.F.: Deformation-Mechanism Maps., 1st. ed. (Pergamon Press, New York,1982), pp. 15, 21, 44Google Scholar
21Watanabe, T., Kimura, S. and Karashima, S.: The effect of a grain boundary structural transformation on sliding in 〈10¯10〉-tilt zinc bicrystals. Philos. Mag. A 49, 845 (1984).CrossRefGoogle Scholar
22Cocks, A.C.F. and Ashby, M.F.: On creep fracture by void growth. Prog. Mater. Sci. 27, 189 (1982).Google Scholar
23Pilling, J. and Ridley, N.: Effect of hydrostatic pressure on cavitation in superplastic aluminium alloys. Acta Metall. 34, 669 (1986).Google Scholar
24Iwasaki, H., Mabuchi, M. and Higashi, K.: Plastic cavity growth during superplastic flow in AA 7475 Al alloy containing a small amount of liquid. Acta Mater. 49, 2269 (2001).Google Scholar