Materials Transactions, Vol.48 No.02 (2007) pp.97-100
© 2007 The Japan Institute of Metals

Role of Eutectic Intermetallic Phase on Creep Strength in a Die-Cast Mg-Al-Ca Alloy: Evaluation by Internal Stress Measurement

Yoshihiro Terada, Yukako Mori and Tatsuo Sato

The internal stress during high temperature creep was investigated for a die-cast Mg-Al-Ca alloy AX52 (X representing calcium) at 473 K through the strain-transient dip test technique. The microstructure of the alloy is characterized by the eutectic intermetallic phase covering the primary α-Mg grains. The eutectic intermetallic phase plays dual roles in enhancing the creep strength from the viewpoint of the internal stress. First, the eutectic intermetallic phase sustains the stress-independent component of the internal stress with the magnitude of 15 MPa, resulting in the decrease in the effective stress. And second, it lowers the creep rate by two orders of magnitude at a given effective stress by reducing the mobile dislocation density and/or glide velocity of dislocations.

(Received 2006/10/13; Accepted 2006/11/10; Published 2007/1/25)

Keywords: magnesium-aluminum-calcium alloy, die-cast, creep, microstructure, internal stress

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REFERENCES

1. B. L. Mordike and T. Ebert: Mater. Sci. Eng. A 302 (2001) 37–45.
2. S. Das: JOM 55 (2003) 22–26.
3. T. Kaneko and M. Suzuki: Mater. Sci. Forum 419–422 (2003) 67–72.
4. E. Aghion, B. Bronfin, F. V. Buch, S. Schumann and H. Friedrich: JOM 55 (2003) 30–33.
5. P. Bakke and H. Westengen: Adv. Eng. Mater. 5 (2003) 879–885.
6. M. O. Pekguleryuz and A. A. Kaya: Adv. Eng. Mater. 5 (2003) 866–878.
7. M. Suzuki, H. Sato, K. Maruyama and H. Oikawa: Mater. Sci. Eng. A 252 (1998) 248–255.
8. Y. Li and T. G. Langdon: Metall. Mater. Trans. A 30A (1999) 2059–2066.
9. K. Maruyama, M. Suzuki and H. Sato: Metall. Mater. Trans. A 33A (2002) 875–882.
10. W. Blum, Y. J. Li, X. H. Zeng, P. Zhang, B. V. Grossmann and C. Haberling: Metall. Mater. Trans. A 36A (2005) 1721–1728.
11. H. Gjestland, G. Nussbaum, G. Regazzoni, O. Lohne and O. Bauger: Mater. Sci. Eng. A 134 (1991) 1197–1200.
12. C. Mendis, L. Bourgeois, B. Muddle and J. F. Nie: Magnesium Technology 2003, ed. by H. I. Kaplan (TMS, Warrendale, 2003) pp.~183–188.
13. Y. Terada, R. Sota, N. Ishimatsu, T. Sato and K. Ohori: Metall. Mater. Trans. A 35A (2004) 3029–3032.
14. M. Vogel, O. Kraft and E. Arzt: Metall. Mater. Trans. A 36A (2005) 1713–1719.
15. R. Ninomiya, T. Ojiro and K. Kubota: Acta Metall. Mater. 43 (1995) 669–674.
16. J. Grobner, D. Kevorkov, I. Chumak and R. Schmid-Fetzer: Z. Metallkde. 94 (2003) 976–982.
17. K. Ozturk, Y. Zhong, A. A. Luo and Z. K. Liu: JOM 55 (2003) 40–44.
18. A. Suzuki, N. D. Saddock, J. W. Jones and T. M. Pollock: Acta Mater. 53 (2005) 2823–2834.
19. Y. Terada, N. Ishimatsu and T. Sato: J. Mater. Res. submitted.
20. J. Cadek: Creep in Metallic Materials, (Elsevier, Amsterdam, 1988).
21. T. Hasegawa, Y. Ikeuchi and S. Karashima: Metal Sci. J. 6 (1972) 78–82.
22. Y. Terada, Y. Mori and T. Sato: Mater. Trans. 47 (2006) 2493–2496.
23. N. Ishimatsu, Y. Terada, T. Sato and K. Ohori: Metall. Mater. Trans. A 37A (2006) 243–248.
24. Y. Mori, Y. Terada and T. Sato: Mater. Trans. 46 (2005) 1749–1752.
25. M. O. Pekguleryuz and J. Renaud: Magnesium Technology 2000, ed. by H. I. Kaplan J. Hryn and B. Clow (TMS, Warrendale, 2000) pp.~279–284.
26. A. A. Luo, M. P. Balogh and B. R. Powell: Metall. Mater. Trans. A 33A (2002) 567–574.
27. A. Suzuki, N. D. Saddock, J. W. Jones and T. M. Pollock: Magnesium Technology 2005, ed. by N. R. Neelameggham, H. I. Kaplan and B. R. Powell (TMS, Warrendale, 2005) pp.~111–116.
28. Y. Terada, N. Ishimatsu, Y. Mori and T. Sato: Mater. Trans. 46 (2005) 145–147.
29. C. N. Ahlquist and W. D. Nix: Scr. Metall. 3 (1969) 679–682.
30. T. Matsuo, K. Nakajima, Y. Terada and M. Kikuchi: Mater. Sci. Eng. A 146 (1991) 261–272.
31. T. B. Massalski: Binary Alloy Phase Diagrams, 2nd edn., (ASM International, Materials Park, 1990).

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