Study of Thermodynamic Properties of Nonstoichiometric Phase with Compound Energy Model

Abstract

Abstract: Using compound energy model (CEM), the thermodynamic properties of and were evaluated. The evaluation was based on the optimization of ZrO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap in CeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solution phases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selected experimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency was obtained and satisfactorily described the complex relation between y in and the partial pressure of oxygen at different temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure, the reduction amount of CeO2 as well as the nonstoichiometry in cubic phase . The calculated results seem to be reasonable when put into the explanation of pressureless sintering of CeO2-stabilized ZrO2 powder compacts at a controlled oxygen partial pressure.

Key words: Zirconia, Ceria, Nonstoichiometry, Thermodynamic

Shuigen HUANG, Lin LI, O.V.D.Biest, J.Vleugels, Peiling WANG. Study of Thermodynamic Properties of Nonstoichiometric Phase with Compound Energy Model[J]. J Mater Sci Technol, 2002, 18(05): 422-426.

References

[1] R.H.J. Hannink, P.M.Kelly and B.C.Muddle: J. Am. Ceram.Soc., 2000, 83(3), 461.
[2] Y.Du, Z.P.Jin and P.Y.Huang: J. Am. Ceram. Soc., 1991,74(7), 1569.
[3] P.Duran, M.Gonzalez, C.Moure, J.R.Jurado and C.Pascual: J.Mater. Sci., 1990, 25(12), 5001.
[4] Karl-Heinz Heussner and Nils Claussen: J. Am. Ceram. Soc.,1989, 72(6), 1044.
[5] E.Tani, M.Yoshimura and S.Somiya: J. Am. Ceram. Soc.,1983, 66, 506.
[6] Lin LI, Zuyao XU and Qing AO: J. Mater. Sci. Tec/mol., 1996,12, 159.
[7] M.Yashima, H.Takshina, M.Kakihana and M.Yoshimura: J.Am. Ceram. Soc., 1994, 77(7), 1869.
[8] Y.Du, M.Yashima, T.Koura, M.Kakihana and M.Yoshimura:Scripta Metall. Mater., 1994, 31(3), 327.
[9] V.Longo and D.Minichelli: J. Am. Ceram. Soc., 1973, 56(11),600.
[10] T.I.Barry, A.T.Dinsdale, J.A.Gisby, B.Hallstedt, M.Hillert,B.Jansson, S. Jonsson, B.Sundman and J.R.Taylor: J. PhaseEquil., 1992, 13, 459.
[11] L.Kaufman and H.Nesor: CALPHAD, 1978, 2, 35.
[12] Lin LI, Shuigen HUANG, Luoping XU, O.V.D.Biest andJ.Vleugels: J. Mater. Sci. Technol., 2001, 17(5), 529.
[13] M.Hillert: J. Alloys Comp., 2001, 320, 161.
[14] B.Sundman: J. Alloys Comp., 1991, 12(1), 127.
[15] W.M.Huang, M.Hillert and X.Z.Wang: Metall. Trans. A,1995, 26a, 2293.
[16] A.Nicholas Grundy, Bengt Hallstedt and Ludwig J.Gauckler:J. Phase Equil, 2001, 22(2), 105.
[17] A.I.Leonov, E.K.K.eler and A.B.Andreeva: Izv. Akad. NaukSSSR, Inorg. Mater., 1966, 2 (6) 1047.
[18] L.B.Pankratz: U. S. Dept. Interior, Bureau of Mines Bulletin672, U. S. Gov't Printing office, Washington, D. C., 1982.
[19] J.Campserveux and P.Gerdanian: J. Solid State Chem., 1978,23(1-2), 73.
[20] Thermo-Calc user's guide, version N. Thermo-Calc SoftwareAB, Stockholm Technology Park. Bjornnasvagen 21, SE-11347 Stockholm, Sweden.
[21] T.B.Lindemer and J.Brynestad: J. Am. Ceram. Soc., 1986,69(12), 867.X