Abstract
An extended unified microsegregation model with solid back diffusion effects and five different dendrite morphologies was used to investigate the solidification path of Al-4.37Cu-27.02Mg (wt.%) ternary eutectic alloy at different cooling rates and solid back diffusion coefficients, coupled with Thermo-Calc. It was indicated that the cooling rates (Rf) had no obvious effect on the solidification path which was (L + α) → (L + α + T) → (L + α + β + T); but the solid back diffusion coefficient (Φ) had a great effect on the solidification path, which evolved gradually from (L + α) → (L + α + T) → (L + α + β + T) into (L + α) → (L + α + T) when Φ increased from 0 to 1. The volume fractions of primary α phase (Vα), binary eutectic (V2E) and ternary eutectic (V3E) at each solidification path were calculated. It was shown that V2E decreased with the increase of Rf whereas V3E increased and Vα was almost invariant. The dependence of V2E, V3E and Rf were determined by linear regression analysis given as: V2E = −2.5lgRf + 47.5; V3E = 6.4lgRf + 47. Increase in Φ lead to increases in Vα and V2E and decrease in V3E. The predicted soldification paths and volume fractions of Al-4.37Cu-27.02Mg ternary eutectic alloy at different cooling rates were in good agreement with experimental results.
References
[1] M.Djordje, G.Joachim, S.F.Rainer: Acta Mater.56 (2008) 5214. 10.1016/j.actamat.2008.07.001Search in Google Scholar
[2] W.Q.Jie, R.J.Zhang, Z.He: Mater. Sci. Eng. A413–414 (2005) 497.Search in Google Scholar
[3] J.N.Dupont: Metal. Trans. A37 (2006) 1937.10.1007/s11661-006-0136-5Search in Google Scholar
[4] T.Fujii, D.R.Poirier, M.C.Flemings: Metall. Trans. B10 (1979) 331. 10.1007/BF02652503Search in Google Scholar
[5] R.Mehrabian, M.C.Flemings: Metal. Trans. B1 (1970) 455. 10.1007/BF02811556Search in Google Scholar
[6] G.E.Fuchs, B.A.Boutwell: JOM2 (2002) 45. 10.1007/BF02822605Search in Google Scholar
[7] X.Yan, S.Chen, F.Xie, Y.A.Chang: Acta Mater.50 (2002) 2199. 10.1016/S1359-6454(01)00431-1Search in Google Scholar
[8] F.Y.Chen, W.Q.Jie: Acta Metall. Sin.40 (2004) 664.Search in Google Scholar
[9] H.Yoo, C.J.Kim: Int. J. Heat Mass Transfer30 (1998) 3268.Search in Google Scholar
[10] A.Roósz, H.E.Exner: Acta Metall. Mater38 (1990) 375. 10.1016/0956-7151(90)90068-RSearch in Google Scholar
[11] F.Y.Xie, T.Kraft, Y.Zuo, C.H.Moon, Y.A.Chang: Acta Metall. Sin.2 (1999) 489.Search in Google Scholar
[12] T.Kraft, M.Rettenmayr, H.E.Exner: Modelling Simul. Mater. Sci. Eng.4 (1996) 161. 10.1088/0965-0393/4/2/004Search in Google Scholar
[13] G.W.Zhao, D.M.Xu, H.Z.Fu: IJMR6 (2008) 680.Search in Google Scholar
[14] J.A.Brooks, M.I.Baskes, F.A.Greulich: Metall. Trans. A22 (1991) 915.Search in Google Scholar
[15] M.C.Flemings, H.D.Brody: Tans. TMS-AIME236 (1966) 615.Search in Google Scholar
[16] T.W.Clyne, W.Kurz: Metall. Trans. A12 (1981) 965. 10.1007/BF02643477Search in Google Scholar
[17] I.Ohnaka: Trans. Iron Steel Inst. Jpn.26 (1986) 1045. 10.2355/isijinternational1966.26.1045Search in Google Scholar
[18] S.Kobayashi: Trans. Iron Steel Inst. Jpn.28 (1988) 728. 10.2355/isijinternational1966.28.728Search in Google Scholar
[19] L.Nastac, D.M.Stefanescu: Metall. Trans. A24 (1993) 2107. 10.1007/BF02666344Search in Google Scholar
[20] D.Larouche: CALPHAD31 (2007) 490. 10.1016/j.calphad.2007.04.002Search in Google Scholar
[21] Q.Du, D.G.Eskin, L.Katgerman: CALPHAD32 (2008) 478. 10.1016/j.calphad.2008.06.007Search in Google Scholar
[22] F.Y.Chen, W.Q.Jie: Acta Metall. Sin.40 (2004) 664.Search in Google Scholar
[23] G.W.Zhao, X.Z.Li, D.M.Xu, J.J.Guo, Y.Du, Y.H.He: CALPHAD, 36 (2012) 155. 10.1016/j.calphad.2011.07.002Search in Google Scholar
[24] T.Buhler, S.G.Fries, P.J.Spencer, H.L.Lukas: J. Phase Equilibria19 (1998) 317. 10.1361/105497198770342058Search in Google Scholar
[25] D.M.Xu: Metall. Mater. Trans. B32 (2001) 1129. 10.1007/s11663-001-0101-zSearch in Google Scholar
[26] D.M.Xu: Metall. Mater. Trans. B33 (2002) 451. 10.1007/s11663-002-0056-8Search in Google Scholar
[27] D.M.Xu, H.Z.Fu, J.J.Guo, J.Jia, Q.C.Li: J. Harbin Institute of Technology35 (2003) 1156.Search in Google Scholar
[28] D.M.Xu, J.J.Guo, H.Z.Fu: SP07-Proceedings of the 5th Decennial International Conference on SolidificationProcessing Sheffield94 (2007) 23.Search in Google Scholar
[29] G.W.Zhao, D.M.Xu, H.Z.Fu, Y.Du, Y.H.He: Acta Metall. Sin.45 (2009) 956.Search in Google Scholar
[30] A.Roósz, P.Barkóczy, J.Farkas: SP07-Proceedings of the 5thDecennial International Conference on Solidification Processing. Sheffield (2007) 365.Search in Google Scholar
[31] X.Doré, H.Combeau, M. Rappaz: Acta Metall. Sin.48 (2000) 3951.Search in Google Scholar
[32] M.C.Flemings: Solidification Processing, McGraw-Hill Book Co., New York, NY, 51 (1974) 134.Search in Google Scholar
[33] W.Kurz, D.J.Fisher: Fundamentals of Solidification, Trans Tech Publications, Aedermannsdorf, Switzerland (1989).Search in Google Scholar
[34] S.N.Singh, B.P.Bardes, M.C.Flemings: Metall. Trans.1 (1970) 1383.Search in Google Scholar
© 2013, Carl Hanser Verlag, München
