Eutectic Solidification in Al-13.0%Si Alloys with Combined Addition of Strontium and Boron

Abstract

Abstract:

The influence of addition of boron (B) on eutectic solidification in a near-eutectic Al-13.0%Si alloy modified with strontium (Sr) was investigated using thermal analysis and macro/microstructure observation. Addition of B in the Sr-modified alloy leads to a considerable increase in nucleation temperature (T_N, the minimum temperature prior to recalescence (T_M) and growth temperature (T_G). In the Sr-modified alloy, nucleation of eutectic might originate at the heterogeneous sites on the mold wall or in the melt near the wall, and eutectic solidification proceeds gradually towards the center, controlled by undercooling of melt. However, with addition of B in the Sr-modified alloy, undercooling required for eutectic nucleation became small, and hence eutectic solidification might occur almost simultaneously within whole casting, controlled by amount of heterogeneous sites. With excessive addition of B in the Sr-modified alloy, nucleation of eutectic grains was explosive within the whole casting and the power of Sr on eutectic solidification was completely poisoned.

Key words: Al-Si alloys, Solidification, Microstructure, Thermal analysis

Hengcheng Liao,Ke Ding,Juanjuan Bi,Min Zhang,Huipin Wang Lei Zhao. Eutectic Solidification in Al-13.0%Si Alloys with Combined Addition of Strontium and Boron[J]. J Mater Sci Technol, 2009, 25(04): 437-440.

References

[1 ] X.F. Liu, Y.Y. Wu and X.F. Bian: J. Alloy. Compd., 2005, 391(1-2), 90.
[2 ] H.C. Liao, Y. Sun and G.X .Sun: Mater. Sci. Eng. A, 2002, 335(1-2), 62.
[3 ] M.M. Haque and A.F. Ismail: J. Mater. Process. Technol., 2005, 162-163, 312.
[4 ] W.M.Wang, J.M. Liu, X.F. Bian, X.Y. Chen and Z.G. Liu: J. Mater. Sci. Lett., 2002, 21(8), 613.
[5 ] H.C. Liao and G.X. Sun: Mater. Sci. Technol., 2004, 20(4), 521.
[6 ] M. Makhlof and H. Guthy: J. Light Metals, 2001, 1, 199 .
[7 ] S. Shankar, Y. Riddle and M. Makhlouf: Acta Mater., 2004, 52, 4447.
[8 ] A.K. Dahle, K. Nogita, J. Zindel, S.D. McDonald and L. Hogan: Metall. Mater. Trans. A, 2001, 32, 949.
[9 ] K. Nogita, S.D. McDonald and A. Dahle: Philos. Mag., 2004, 84, 1683.
[10] A.K. Dahle, K. Nogita, S.D. McDonald, C. Dinnis and L.Lu: Mater. Sci. Eng. A, 2005, 413-414, 243.
[11] S.D. McDonald, K. Nogita and A.K. Dahle: Acta Mater., 2004, 52, 4273.
[12] K. Nogita, S.D. McDonald, C. Dinnis, L. Lu and A.K. Dahle: Solidification of Aluminum Alloys, Eds. M.G. Chu, D.A .Granger and Qingyou Han, TMS (The Minerals, Metal & Materials Society), 2004, 93.
[13] A.K. Dahle, S.D. McDonald and K. Nogita: Proceedings from the 2nd International Aluminum Casting Technology Symposium, Columbus, OH, ASM International, 2002, 1.
[14] H.C. Liao, Z.P. Wu, G.M. Dong, J. Chen and G.X. Sun: Acta Metall. Sin., 2005, 41(10), 1047. (in Chinese)
[15] H.C. Liao, M. Zhang, Q.C. Wu, H.P. Wang and G.X. Sun: Scripta Mater., 2007, 57(12), 1121.
[16] H.C. Liao, H.P.Wang, M. Zhang, G.M. Dong and G.X. Sun: MS&T2007 Meeting: Automotive Light Metal Casting, Technology and Applications, Detroit, MI, USA, 2007, 469.
[17] J. Tamminen: Thermal Analysis for Investigation of Solidification Mechanisms in Metals and Alloys, Ph.D. Thesis, Stockholm University, 1988, 35-40.
[18] S.Z. Lu and A. Hellawell: JOM, 1995, 47, 38.
[19] D. Apelian and J. Chen: AFS Trans., 1986, 94, 797.
[20] L. Heusler and W. Schneider: J. Light Metals, 2002, 2, 17.
[21] H.C. Liao and G.X. Sun: Scripta Mater., 2003, 48(8), 1035.
[22] H.C. Liao and G.X. Sun: Acta Metall. Sin., 2003, 39(2), 156. (in Chinese)

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