Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-29T10:41:07.388Z Has data issue: false hasContentIssue false
  • English
  • Français

Microstructural investigation and thermodynamic calculations on the precipitation of Mg–Al–Zn–Sr alloys

Published online by Cambridge University Press:  02 March 2011

Alireza Sadeghi  and
Mihriban Pekguleryuz
Alireza Sadeghi*
Affiliation:
Department of Mining and Materials Science, McGill University, Montreal, Quebec H3A 2B2, Canada
Mihriban Pekguleryuz
Affiliation:
Department of Mining and Materials Science, McGill University, Montreal, Quebec H3A 2B2, Canada
*
a)Address all correspondence to this author. e-mail: Alireza.Sadeghi@mail.mcgill.ca
Get access

Abstract

Microstructural investigation and thermodynamic simulation were carried out to study precipitation during the solidification of AZ31 Mg alloy containing up to 1wt% Sr. Increasing Sr content from 0.01 to 1 wt% led to the formation of an Al–Sr line compound (Al4Sr) and to the suppression of Al–Mg precipitate (β-Mg17Al12). Transmission electron microscopic (TEM) investigation and energy dispersive spectroscopic analysis on extracted precipitates revealed Mg and Zn solubility in the Al4Sr particles. It is shown that Sr content also affects the precipitation of Al–Mn precipitates. Thermodynamic calculations predict that the increase in Sr content limits the Al–Mn reaction and the precipitation of Al–Mn precipitates with low Al/Mn ratio. Microstructural investigations determined the presence of two Al–Mn precipitates (Al8Mn5 and AlMn), either in the form of large dendritic plates or small nano-scale particles in the Mg matrix. It has been calculated by the thermodynamic model and confirmed by TEM that by increasing the Sr content, solubility of Al solid decreases whereas the level of Mn increases slightly.

Keywords

MgSrPhase Equilibria
Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 7 , 14 April 2011 , pp. 896 - 903
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Koubichek, L.: Effect of small additions of elements on grain size and the refinement of the mg4al3 [mg17al12] phase in ml5 alloy. Izv. Vyschikh. Outchebnykh Za Vedeny. Metallurgy of Non-Ferrous Metals, 6, (1959).Google Scholar
2.King, H.W.: Solid solution and intermetallic phases containing strontium, in International Conference on Strontium Containing Compounds, NRC, Ottawa, Canada, 1973, pp. 212–243.Google Scholar
3.Aliravci, C.A., Gruzleski, J.E., and Dimayuga, F.C.: Effect of Strontium on the shrinkage microporosity in magnesium sand castings. AFS Trans. 92, (1992).Google Scholar
4.Pekguleryuz, M.O. and Avedesian, M.M.: Magnesium Alloying—Some Metallurgical Aspects: Magnesium Alloys and Their Applications, edited by Mordike, B.L. and Hehman, F. (DGM, Germany, 1992), pp. 679–686.Google Scholar
5.Pekguleryuz, M., Baril, E., Labelle, P., and Argo, D.: Creep resistant Mg–Al–Sr alloys. J. Adv. Mat. 35(3), 32 (2003).Google Scholar
6.Pekguleryuz, M.O. and Kaya, A.A.: Magnesium diecasting alloys for high temperature applications, in Magnesium Technology, edited by Luo, A. (TMS, Charlotte, NC, 2004), pp. 281–287.Google Scholar
7.Kunst, M., Fischersworring-Bunka, A., L’Esperanceb, G., Plamondonb, P., and Glatzelc, U.: Microstructure and dislocation analysis after creep deformation of die-cast Mg–Al–Sr (AJ) alloy. Mater. Sci. Eng. A, 510–511 (2009).CrossRefGoogle Scholar
8.Baril, E., Labelle, P., and Pekguleryuz, M.O.: Elevated temperature Mg–Al–Sr: Creep resistance, mechanical properties and microstructure. JOM-US. 55(11), 34 (2003).CrossRefGoogle Scholar
9.Pekguleryuz, M.O. and Baril, E.: The minerals, metals and materials society, in Magnesium Technology 2001, edited by Hryn, J.N. (TMS, Warrendale, PA, 2001).Google Scholar
10.Jing, B., Yangshan, S., Shan, X., Feng, X., and Tianbai, Z.: Microstructure and tensile creep behavior of Mg–4Al based magnesium alloys with alkaline-earth elements Sr and Ca additions. Mater. Sci. Eng. A 419, 181 (2006).CrossRefGoogle Scholar
11.Zeng, X., Wang, Y., Ding, W., Luo, A.A., and Sachdev, A.K.: Effect of strontium on the microstructure, mechanical properties, and fracture behavior of AZ31 magnesium alloy. Metall. Mater. Trans. A 37(4), 1073 (2006).CrossRefGoogle Scholar
12.Zhao, P., Wang, Q., Zhai, C., and Zhu, Y.: Effects of strontium and titanium on the microstructure, tensile properties and creep behavior of AM50 alloys. Mater. Sci. Eng. A 444, 318 (2007).CrossRefGoogle Scholar
13.Sadeghi, A. and Pekguleryuz, M.: Precipitation during the solidification of Mg–3wt% Al–1wt% Zn–(0.001–1%) Sr alloys, in American Foundry Society Annual Congress, Orlando, USA, (2010), pp. 10–114.Google Scholar
14.Guan, S., Zhu, S., Wang, L., Yang, Q., and Cao, W.: Microstructures and mechanical properties of double hot-extruded AZ80 + xSr wrought alloys. Trans. Nonferrous Met. Soc. China 17(6), 1143 (2007).CrossRefGoogle Scholar
15.Jing, B., Yangshan, S., Feng, X., Shan, X., Jinga, Q., and Weijianb, T.: Effect of extrusion on microstructures, and mechanical and creep properties of Mg–Al–Sr and Mg–Al–Sr–Ca alloys. Scr. Mater. 55, 1163 (2006).CrossRefGoogle Scholar
16.Janz, A., Gröbner, J., Mirković, D., Medraj, M., and Jun Zhu, Y.A., Chang, , and Schmid-Fetzer, R.: Experimental study and thermodynamic calculation of Al–Mg–Sr phase equilibria. Intermetallics 15, 506 (2007).CrossRefGoogle Scholar
17.Janz, A., Gröbner, J., and Schmid-Fetzer, R.: Thermodynamics and constitution of Mg–Al–Ca–Sr–Mn alloys—Part II—Procedure for multicomponent key sample selection and application to the Mg–Al–Ca–Sr and Mg–Al–Ca–Sr–Mn systems. J. Phase Equilib. Diffus. 30, 157 (2009).CrossRefGoogle Scholar
18.Gruzleski, J.E. and Aliravci, A.: Low Porosity, Fine-grain Sized Strontium Treated Magnesium Alloy Castings. U.S. Patent No. US005143564A (1992).Google Scholar
19.L’Esperance, G., Plamondon, P., Kunst, M., and Fischersworring-Bunk, A.: Characterization of intermetallics in Mg–Al–Sr AJ62 alloys. Intermetallics 18, 1 (2010).CrossRefGoogle Scholar
20.Liu, S.F., Li, B., Wang, X.H., Su, W., and Han, H.: Refinement effect of cerium, calcium and strontium in AZ91 magnesium alloy. J. Mater. Process. Technol. 209(8), 3999 (2009).CrossRefGoogle Scholar
21.Becerra, A. and Pekguleryuz, M.: Effects of lithium, indium and zinc on the grain size of magnesium. J. Mater. Res. 24(5), 1722 (2009).CrossRefGoogle Scholar
22.Avedesian, M.M. and Baker, H.: Magnesium and Magnesium Alloys (ASM International, Materials Park, OH, 1999).Google Scholar